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Chronic Kidney Disease

Chronic kidney disease (CKD) is kidney impairment that lasts for ≥ 3 months, implying that it is irreversible. Hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension and diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus are the most common causes; however, there are a multitude of other etiologies. In the early to moderate stages, CKD is usually asymptomatic and is primarily diagnosed by laboratory abnormalities. Regardless of the etiology, progression of renal impairment is common and can ultimately lead to end-stage renal disease and the need for renal replacement therapy (e.g., transplantation or dialysis Dialysis Renal replacement therapy refers to dialysis and/or kidney transplantation. Dialysis is a procedure by which toxins and excess water are removed from the circulation. Hemodialysis and peritoneal dialysis (PD) are the two types of dialysis, and their primary difference is the location of the filtration process (external to the body in hemodialysis versus inside the body for PD). Peritoneal Dialysis and Hemodialysis). The management of CKD includes treating the underlying etiology, aggressive risk factor modification, and addressing complications such as fluid overload and electrolyte imbalances.

Last updated: Dec 5, 2022

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Overview

Definition

Chronic kidney disease (CKD) is typically defined as a decrease in kidney function and/or other signs of persistent kidney damage for ≥ 3 months. These signs include:

  • GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests (Note: CKD patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship can have a normal GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests.)
  • Proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children
  • Glomerular hematuria Hematuria Presence of blood in the urine. Renal Cell Carcinoma
  • Imaging findings
  • Pathologic findings on kidney biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma

Epidemiology

  • Prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency:
    • Approximately 10% worldwide
    • Highest prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency in Taiwan, Japan, and the United States
  • Mortality Mortality All deaths reported in a given population. Measures of Health Status: approximately 66% after 5 years on dialysis Dialysis Renal replacement therapy refers to dialysis and/or kidney transplantation. Dialysis is a procedure by which toxins and excess water are removed from the circulation. Hemodialysis and peritoneal dialysis (PD) are the two types of dialysis, and their primary difference is the location of the filtration process (external to the body in hemodialysis versus inside the body for PD). Peritoneal Dialysis and Hemodialysis
  • Sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria: ↑ Risk of disease progression in men
  • Race/ethnicity:
    • Highest rates in people of African descent:
      • Potentially due to ↑ rates of APOL1 mutations, which are associated with ↑ risk for early-onset kidney disease
      • APOL1 mutations are believed to provide resistance Resistance Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow. Ventilation: Mechanics of Breathing against disease-causing trypanosomes
    • Hispanics have ↑ rates as compared with non-Hispanics

Etiology

Similar to AKI AKI Acute kidney injury refers to sudden and often reversible loss of renal function, which develops over days or weeks. Azotemia refers to elevated levels of nitrogen-containing substances in the blood that accompany AKI, which include BUN and creatinine. Acute Kidney Injury, the causes of CKD can be classified as prerenal, intrinsic renal, or postrenal. Diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus and hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension are, by a large margin, the most common causes of CKD.

Table: Etiologies of CKD
Location of disease Examples
Prerenal (vascular) disease
Glomerular disease
  • Diabetic nephropathy Diabetic nephropathy Kidney injuries associated with diabetes mellitus and affecting kidney glomerulus; arterioles; kidney tubules; and the interstitium. Clinical signs include persistent proteinuria, from microalbuminuria progressing to albuminuria of greater than 300 mg/24 h, leading to reduced glomerular filtration rate and end-stage renal disease. Chronic Diabetic Complications
  • Primary glomerular disease:
    • IgA IgA Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory iga is the main immunoglobulin in secretions. Immunoglobulins: Types and Functions nephropathy
    • Lupus nephritis Lupus nephritis Glomerulonephritis associated with autoimmune disease systemic lupus erythematosus. Lupus nephritis is histologically classified into 6 classes: class I – normal glomeruli, class II – pure mesangial alterations, class III – focal segmental glomerulonephritis, class IV – diffuse glomerulonephritis, class V – diffuse membranous glomerulonephritis, and class VI – advanced sclerosing glomerulonephritis (the world health organization classification 1982). Diffuse Proliferative Glomerulonephritis ( systemic lupus erythematosus Systemic lupus erythematosus Systemic lupus erythematosus (SLE) is a chronic autoimmune, inflammatory condition that causes immune-complex deposition in organs, resulting in systemic manifestations. Women, particularly those of African American descent, are more commonly affected. Systemic Lupus Erythematosus ( SLE SLE Systemic lupus erythematosus (SLE) is a chronic autoimmune, inflammatory condition that causes immune-complex deposition in organs, resulting in systemic manifestations. Women, particularly those of African American descent, are more commonly affected. Systemic Lupus Erythematosus))
Tubulointerstitial disease
  • Polycystic kidney disease (PKD):
  • Secondary to autoimmune disease:
    • Sjögren syndrome Sjögren Syndrome Rheumatoid Arthritis
    • Sarcoidosis Sarcoidosis Sarcoidosis is a multisystem inflammatory disease that causes noncaseating granulomas. The exact etiology is unknown. Sarcoidosis usually affects the lungs and thoracic lymph nodes, but it can also affect almost every system in the body, including the skin, heart, and eyes, most commonly. Sarcoidosis
  • Chronic interstitial nephritis (e.g., NSAID NSAID Nonsteroidal antiinflammatory drugs (NSAIDs) are a class of medications consisting of aspirin, reversible NSAIDs, and selective NSAIDs. NSAIDs are used as antiplatelet, analgesic, antipyretic, and antiinflammatory agents. Nonsteroidal Antiinflammatory Drugs (NSAIDs) nephropathy)
  • Vesicoureteral reflux Vesicoureteral Reflux Vesicoureteral reflux (VUR) is the retrograde flow of urine from the bladder into the upper urinary tract. Primary VUR often results from the incomplete closure of the ureterovesical junction, whereas secondary VUR is due to an anatomic or physiologic obstruction. Vesicoureteral Reflux (Reflux causes a tubulointerstitial nephropathy, so this is typically classified here rather than as a postrenal cause.)
Postrenal disease
  • Benign Benign Fibroadenoma prostatic hyperplasia Hyperplasia An increase in the number of cells in a tissue or organ without tumor formation. It differs from hypertrophy, which is an increase in bulk without an increase in the number of cells. Cellular Adaptation ( BPH BPH Benign prostatic hyperplasia (bph) is a condition indicating an increase in the number of stromal and epithelial cells within the prostate gland (transition zone). Benign prostatic hyperplasia is common in men > 50 years of age and may greatly affect their quality of life. Benign Prostatic Hyperplasia)
  • Urethral stricture Stricture Primary Sclerosing Cholangitis
  • Bilateral obstructing kidney stones Kidney stones Nephrolithiasis is the formation of a stone, or calculus, anywhere along the urinary tract caused by precipitations of solutes in the urine. The most common type of kidney stone is the calcium oxalate stone, but other types include calcium phosphate, struvite (ammonium magnesium phosphate), uric acid, and cystine stones. Nephrolithiasis
  • Pelvic mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast
Other causes AKI AKI Acute kidney injury refers to sudden and often reversible loss of renal function, which develops over days or weeks. Azotemia refers to elevated levels of nitrogen-containing substances in the blood that accompany AKI, which include BUN and creatinine. Acute Kidney Injury episodes that do not fully recover

Pathophysiology of CKD and Its Complications

Pathophysiology of CKD

CKD can be caused by a multitude of underlying conditions; however, once about half of the total nephrons are lost, CKD progresses similarly, regardless of etiology.

  • Underlying etiology: ↓ total number of nephrons ( nephron Nephron The functional units of the kidney, consisting of the glomerulus and the attached tubule. Kidneys: Anatomy mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast), which leads to:
    • ↑ Glomerular permeability → ↑ filtration of proteins Proteins Linear polypeptides that are synthesized on ribosomes and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of amino acids determines the shape the polypeptide will take, during protein folding, and the function of the protein. Energy Homeostasis, which are lost in the urine (i.e., proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children
    • Activation of the RAAS RAAS A blood pressure regulating system of interacting components that include renin; angiotensinogen; angiotensin converting enzyme; angiotensin i; angiotensin ii; and angiotensinase. Renin, an enzyme produced in the kidney, acts on angiotensinogen, an alpha-2 globulin produced by the liver, forming angiotensin I. Angiotensin-converting enzyme, contained in the lung, acts on angiotensin I in the plasma converting it to angiotensin II, an extremely powerful vasoconstrictor. Angiotensin II causes contraction of the arteriolar and renal vascular smooth muscle, leading to retention of salt and water in the kidney and increased arterial blood pressure. In addition, angiotensin II stimulates the release of aldosterone from the adrenal cortex, which in turn also increases salt and water retention in the kidney. Angiotensin-converting enzyme also breaks down bradykinin, a powerful vasodilator and component of the kallikrein-kinin system. Adrenal Hormones
    • Cytokine release
    • ↑ Growth factors
  • These changes lead to adaptive hyperfiltration:
    • GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests may actually ↑ during this time.
    • Occurs as a compensatory mechanism
    • Leads to ↑ intraglomerular capillary pressure (i.e., glomerular hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension)
  • ↑ Intraglomerular capillary pressure and inflammatory mediators cause damage to the remaining nephrons.
  • Damage to the remaining nephrons continues the positive feedback loop, and CKD progresses.
Chronic kidney disease pathophysiology

Common pathogenesis of CKD, independent of initial etiology

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Pathogenesis of hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension as a result of CKD

Hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension is not just one of the most common causes of CKD, it can also result from CKD by the following mechanisms:

  • Na+ and fluid retention
  • RAAS RAAS A blood pressure regulating system of interacting components that include renin; angiotensinogen; angiotensin converting enzyme; angiotensin i; angiotensin ii; and angiotensinase. Renin, an enzyme produced in the kidney, acts on angiotensinogen, an alpha-2 globulin produced by the liver, forming angiotensin I. Angiotensin-converting enzyme, contained in the lung, acts on angiotensin I in the plasma converting it to angiotensin II, an extremely powerful vasoconstrictor. Angiotensin II causes contraction of the arteriolar and renal vascular smooth muscle, leading to retention of salt and water in the kidney and increased arterial blood pressure. In addition, angiotensin II stimulates the release of aldosterone from the adrenal cortex, which in turn also increases salt and water retention in the kidney. Angiotensin-converting enzyme also breaks down bradykinin, a powerful vasodilator and component of the kallikrein-kinin system. Adrenal Hormones activity
  • ↑ Sympathetic nervous system Nervous system The nervous system is a small and complex system that consists of an intricate network of neural cells (or neurons) and even more glial cells (for support and insulation). It is divided according to its anatomical components as well as its functional characteristics. The brain and spinal cord are referred to as the central nervous system, and the branches of nerves from these structures are referred to as the peripheral nervous system. Nervous System: Anatomy, Structure, and Classification activity
  • Vasoconstriction Vasoconstriction The physiological narrowing of blood vessels by contraction of the vascular smooth muscle. Vascular Resistance, Flow, and Mean Arterial Pressure from ↑ Ca CA Condylomata acuminata are a clinical manifestation of genital HPV infection. Condylomata acuminata are described as raised, pearly, flesh-colored, papular, cauliflower-like lesions seen in the anogenital region that may cause itching, pain, or bleeding. Condylomata Acuminata (Genital Warts)2+ due to secondary hyperparathyroidism Secondary hyperparathyroidism Abnormally elevated parathyroid hormone secretion as a response to hypocalcemia. It is caused by chronic kidney failure or other abnormalities in the controls of bone and mineral metabolism, leading to various bone diseases, such as renal osteodystrophy. Hyperparathyroidism
  • Impaired vasomediators (↓ nitric oxide Nitric Oxide A free radical gas produced endogenously by a variety of mammalian cells, synthesized from arginine by nitric oxide synthase. Nitric oxide is one of the endothelium-dependent relaxing factors released by the vascular endothelium and mediates vasodilation. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic guanylate cyclase and thus elevates intracellular levels of cyclic gmp. Pulmonary Hypertension Drugs, endothelium-mediated vasodilation Vasodilation The physiological widening of blood vessels by relaxing the underlying vascular smooth muscle. Pulmonary Hypertension Drugs)

Pathogenesis of secondary hyperparathyroidism Secondary hyperparathyroidism Abnormally elevated parathyroid hormone secretion as a response to hypocalcemia. It is caused by chronic kidney failure or other abnormalities in the controls of bone and mineral metabolism, leading to various bone diseases, such as renal osteodystrophy. Hyperparathyroidism

Secondary hyperparathyroidism Secondary hyperparathyroidism Abnormally elevated parathyroid hormone secretion as a response to hypocalcemia. It is caused by chronic kidney failure or other abnormalities in the controls of bone and mineral metabolism, leading to various bone diseases, such as renal osteodystrophy. Hyperparathyroidism (also known as mineral and bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types disease) is an important complication of CKD.

  • GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests → ↓ urinary phosphate Phosphate Inorganic salts of phosphoric acid. Electrolytes excretion → ↑ serum phosphate Phosphate Inorganic salts of phosphoric acid. Electrolytes (PO43–) → ↑ fibroblast growth factor Fibroblast growth factor A family of small polypeptide growth factors that share several common features including a strong affinity for heparin, and a central barrel-shaped core region of 140 amino acids that is highly homologous between family members. Although originally studied as proteins that stimulate the growth of fibroblasts this distinction is no longer a requirement for membership in the fibroblast growth factor family. X-linked Hypophosphatemic Rickets 23 (FGF-23) (a regulatory mechanism) 
  • ↑ FGF-23:
    • ↓ PO43– reabsorption:
      • ↑ PO43– excretion
      • Eventually the ↑ serum PO43– overwhelms the FGF-23 regulatory system and leads to ↑ parathyroid Parathyroid The parathyroid glands are 2 pairs of small endocrine glands found in close proximity to the thyroid gland. The superior parathyroid glands are lodged within the parenchyma of the upper poles of the right and left thyroid lobes; the inferior parathyroid glands are close to the inferior tips or poles of the lobes. Parathyroid Glands: Anatomy hormone (PTH) secretion Secretion Coagulation Studies (i.e., secondary hyperparathyroidism Secondary hyperparathyroidism Abnormally elevated parathyroid hormone secretion as a response to hypocalcemia. It is caused by chronic kidney failure or other abnormalities in the controls of bone and mineral metabolism, leading to various bone diseases, such as renal osteodystrophy. Hyperparathyroidism).
    • FGF-23 also inhibits 1𝛼-hydroxylase:
      • 1𝛼-hydroxylase converts 25-hydroxyvitamin D (25(OH)D) into 1,25(OH)D ( calcitriol Calcitriol The physiologically active form of vitamin d. It is formed primarily in the kidney by enzymatic hydroxylation of 25-hydroxycholecalciferol (calcifediol). Its production is stimulated by low blood calcium levels and parathyroid hormone. Calcitriol increases intestinal absorption of calcium and phosphorus, and in concert with parathyroid hormone increases bone resorption. Parathyroid Glands: Anatomy)
      • Calcitriol Calcitriol The physiologically active form of vitamin d. It is formed primarily in the kidney by enzymatic hydroxylation of 25-hydroxycholecalciferol (calcifediol). Its production is stimulated by low blood calcium levels and parathyroid hormone. Calcitriol increases intestinal absorption of calcium and phosphorus, and in concert with parathyroid hormone increases bone resorption. Parathyroid Glands: Anatomy → ↓ GI Ca CA Condylomata acuminata are a clinical manifestation of genital HPV infection. Condylomata acuminata are described as raised, pearly, flesh-colored, papular, cauliflower-like lesions seen in the anogenital region that may cause itching, pain, or bleeding. Condylomata Acuminata (Genital Warts)2+ absorption Absorption Absorption involves the uptake of nutrient molecules and their transfer from the lumen of the GI tract across the enterocytes and into the interstitial space, where they can be taken up in the venous or lymphatic circulation. Digestion and Absorption → ↓ serum Ca CA Condylomata acuminata are a clinical manifestation of genital HPV infection. Condylomata acuminata are described as raised, pearly, flesh-colored, papular, cauliflower-like lesions seen in the anogenital region that may cause itching, pain, or bleeding. Condylomata Acuminata (Genital Warts)2+ → ↑ PTH
  • Consequences of secondary hyperparathyroidism Secondary hyperparathyroidism Abnormally elevated parathyroid hormone secretion as a response to hypocalcemia. It is caused by chronic kidney failure or other abnormalities in the controls of bone and mineral metabolism, leading to various bone diseases, such as renal osteodystrophy. Hyperparathyroidism:
    • Vascular calcification (↑ morbidity Morbidity The proportion of patients with a particular disease during a given year per given unit of population. Measures of Health Status from cardiovascular disease)
    • Renal osteodystrophy Osteodystrophy Cirrhosis (↑ morbidity Morbidity The proportion of patients with a particular disease during a given year per given unit of population. Measures of Health Status from trochanteric fractures), which may present as:
      • Osteomalacia Osteomalacia Disorder caused by an interruption of the mineralization of organic bone matrix leading to bone softening, bone pain, and weakness. It is the adult form of rickets resulting from disruption of vitamin d; phosphorus; or calcium homeostasis. Osteomalacia and Rickets
      • Osteitis fibrosa (high-turnover bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types disease)
      • Mixed uremic bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types disease ( osteomalacia Osteomalacia Disorder caused by an interruption of the mineralization of organic bone matrix leading to bone softening, bone pain, and weakness. It is the adult form of rickets resulting from disruption of vitamin d; phosphorus; or calcium homeostasis. Osteomalacia and Rickets + osteitis fibrosa)
      • Adynamic bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types disease ( iatrogenic Iatrogenic Any adverse condition in a patient occurring as the result of treatment by a physician, surgeon, or other health professional, especially infections acquired by a patient during the course of treatment. Anterior Cord Syndrome from therapeutic oversuppression of PTH)
Mechanism of secondary hyperparathyroidism in ckd

Mechanism of secondary hyperparathyroidism in CKD
FGF-23: fibroblast growth factor 23

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Pathophysiology of anemia Anemia Anemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types in chronic kidney disease

  • Kidney disease → ↓ production of erythropoietin Erythropoietin Glycoprotein hormone, secreted chiefly by the kidney in the adult and the liver in the fetus, that acts on erythroid stem cells of the bone marrow to stimulate proliferation and differentiation. Erythrocytes: Histology → ↓ production of RBCs RBCs Erythrocytes, or red blood cells (RBCs), are the most abundant cells in the blood. While erythrocytes in the fetus are initially produced in the yolk sac then the liver, the bone marrow eventually becomes the main site of production. Erythrocytes: Histology
  • Defined as a hemoglobin level:
    • < 13 g/dL in men and postmenopausal women
    • < 12 g/dL in premenopausal women

Clinical Presentation

Often, CKD disease remains asymptomatic until the late stages, despite a significant decrease in GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests during the earlier stages. Also, CKD is often either found incidentally on labs or it presents with complications.

  • Incidentally discovered on lab work:
    • Routine monitoring of serum creatinine
    • Routine albuminuria Albuminuria The presence of albumin in the urine, an indicator of kidney diseases. Kidney Function Tests screening Screening Preoperative Care for diabetics
    • Hematuria Hematuria Presence of blood in the urine. Renal Cell Carcinoma and/or proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children found on urinalysis Urinalysis Examination of urine by chemical, physical, or microscopic means. Routine urinalysis usually includes performing chemical screening tests, determining specific gravity, observing any unusual color or odor, screening for bacteriuria, and examining the sediment microscopically. Urinary Tract Infections (UTIs) in Children for other reasons (e.g., urinary tract Urinary tract The urinary tract is located in the abdomen and pelvis and consists of the kidneys, ureters, urinary bladder, and urethra. The structures permit the excretion of urine from the body. Urine flows from the kidneys through the ureters to the urinary bladder and out through the urethra. Urinary Tract: Anatomy infection) 
  • Hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension: 80%–85% prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency in CKD regardless of etiology 
  • Signs of volume overload:
    • Lower-extremity edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema
    • Elevated jugular venous pressure Jugular Venous Pressure Portal Hypertension 
    • S3 gallop S3 gallop Heart Failure on cardiac auscultation
    • Crackles on pulmonary auscultation
    • New or increasing requirement for supplemental oxygen Supplemental Oxygen Respiratory Failure
    • Ascites Ascites Ascites is the pathologic accumulation of fluid within the peritoneal cavity that occurs due to an osmotic and/or hydrostatic pressure imbalance secondary to portal hypertension (cirrhosis, heart failure) or non-portal hypertension (hypoalbuminemia, malignancy, infection). Ascites
  • Signs of uremia Uremia A clinical syndrome associated with the retention of renal waste products or uremic toxins in the blood. It is usually the result of renal insufficiency. Most uremic toxins are end products of protein or nitrogen catabolism, such as urea or creatinine. Severe uremia can lead to multiple organ dysfunctions with a constellation of symptoms. Acute Kidney Injury:
    • Nausea Nausea An unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses. Antiemetics, vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia, and anorexia Anorexia The lack or loss of appetite accompanied by an aversion to food and the inability to eat. It is the defining characteristic of the disorder anorexia nervosa. Anorexia Nervosa
    • Altered mental status Altered Mental Status Sepsis in Children 
    • Asterixis Asterixis Hepatic Encephalopathy (“ flapping tremor Flapping Tremor Hepatic Encephalopathy” of the hands)
    • Friction rub on cardiac auscultation (sign of pericardial effusion Pericardial effusion Fluid accumulation within the pericardium. Serous effusions are associated with pericardial diseases. Hemopericardium is associated with trauma. Lipid-containing effusion (chylopericardium) results from leakage of thoracic duct. Severe cases can lead to cardiac tamponade. Pericardial Effusion and Cardiac Tamponade)
    • Skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions excoriations Excoriations Excoriation is a linear abrasion produced by mechanical means (scratching, rubbing, or picking) that usually involves only the epidermis but can reach the papillary dermis. Secondary Skin Lesions from pruritus Pruritus An intense itching sensation that produces the urge to rub or scratch the skin to obtain relief. Atopic Dermatitis (Eczema)
    • Uremic frost ( urea Urea A compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids. Urea Cycle crystals deposited in the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions)
  • Specific exam findings by etiology:
    • Retinopathy Retinopathy Degenerative changes to the retina due to hypertension. Alport Syndrome (hypertensive nephrosclerosis Nephrosclerosis Hardening of the kidney due to infiltration by fibrous connective tissue (fibrosis), usually caused by renovascular diseases or chronic hypertension. Nephrosclerosis leads to renal ischemia. Liddle Syndrome, diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus)
    • Abdominal bruit Abdominal Bruit Abdominal Examination ( renal artery Renal artery A branch of the abdominal aorta which supplies the kidneys, adrenal glands and ureters. Glomerular Filtration stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS)
    • Livedo reticularis rash Rash Rocky Mountain Spotted Fever, particularly on the toes ( cholesterol Cholesterol The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils. Cholesterol Metabolism emboli)
    • Easily palpable kidneys Kidneys The kidneys are a pair of bean-shaped organs located retroperitoneally against the posterior wall of the abdomen on either side of the spine. As part of the urinary tract, the kidneys are responsible for blood filtration and excretion of water-soluble waste in the urine. Kidneys: Anatomy (PKD)
    • Periorbital Periorbital Orbital and Preseptal Cellulitis edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema ( nephrotic syndrome Nephrotic syndrome Nephrotic syndrome is characterized by severe proteinuria, hypoalbuminemia, and peripheral edema. In contrast, the nephritic syndromes present with hematuria, variable loss of renal function, and hypertension, although there is sometimes overlap of > 1 glomerular disease in the same individual. Nephrotic Syndrome)
    • Gross hematuria Hematuria Presence of blood in the urine. Renal Cell Carcinoma ( IgA IgA Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory iga is the main immunoglobulin in secretions. Immunoglobulins: Types and Functions nephropathy)
    • Other characteristic signs of autoimmune diseases Autoimmune diseases Disorders that are characterized by the production of antibodies that react with host tissues or immune effector cells that are autoreactive to endogenous peptides. Selective IgA Deficiency (e.g., malar rash Malar Rash Systemic Lupus Erythematosus in SLE SLE Systemic lupus erythematosus (SLE) is a chronic autoimmune, inflammatory condition that causes immune-complex deposition in organs, resulting in systemic manifestations. Women, particularly those of African American descent, are more commonly affected. Systemic Lupus Erythematosus)
  • Complications:
    • Cardiovascular disease (clinically most important): chest pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways, dyspnea Dyspnea Dyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea on exertion
    • Mineral and bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types disease ( secondary hyperparathyroidism Secondary hyperparathyroidism Abnormally elevated parathyroid hormone secretion as a response to hypocalcemia. It is caused by chronic kidney failure or other abnormalities in the controls of bone and mineral metabolism, leading to various bone diseases, such as renal osteodystrophy. Hyperparathyroidism): bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways, fractures
    • Anemia Anemia Anemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types: fatigue Fatigue The state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli. Fibromyalgia, dyspnea Dyspnea Dyspnea is the subjective sensation of breathing discomfort. Dyspnea is a normal manifestation of heavy physical or psychological exertion, but also may be caused by underlying conditions (both pulmonary and extrapulmonary). Dyspnea on exertion, pallor
    • Hyperkalemia Hyperkalemia Hyperkalemia is defined as a serum potassium (K+) concentration >5.2 mEq/L. Homeostatic mechanisms maintain the serum K+ concentration between 3.5 and 5.2 mEq/L, despite marked variation in dietary intake. Hyperkalemia can be due to a variety of causes, which include transcellular shifts, tissue breakdown, inadequate renal excretion, and drugs. Hyperkalemia: muscle weakness, cardiac arrhythmias

Diagnosis

The initial diagnosis of CKD is by finding a decreased GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests, hematuria Hematuria Presence of blood in the urine. Renal Cell Carcinoma, proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children, or abnormal imaging. An assessment should then be made to determine the underlying etiology.

General workup

The general workup for CKD includes:

  • History and physical exam
  • Serum labs:
    • Creatinine to obtain the estimated GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests (eGFR; see below)
    • Screen for diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus.
    • Other findings common in CKD:
      • Anemia Anemia Anemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types (present in 90% of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with a GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests < 30 mL/min)
      • Hyperkalemia Hyperkalemia Hyperkalemia is defined as a serum potassium (K+) concentration >5.2 mEq/L. Homeostatic mechanisms maintain the serum K+ concentration between 3.5 and 5.2 mEq/L, despite marked variation in dietary intake. Hyperkalemia can be due to a variety of causes, which include transcellular shifts, tissue breakdown, inadequate renal excretion, and drugs. Hyperkalemia
      • Metabolic acidosis Acidosis A pathologic condition of acid accumulation or depletion of base in the body. The two main types are respiratory acidosis and metabolic acidosis, due to metabolic acid build up. Respiratory Acidosis
      • Secondary hyperparathyroidism Secondary hyperparathyroidism Abnormally elevated parathyroid hormone secretion as a response to hypocalcemia. It is caused by chronic kidney failure or other abnormalities in the controls of bone and mineral metabolism, leading to various bone diseases, such as renal osteodystrophy. Hyperparathyroidism: ↑ serum phosphate Phosphate Inorganic salts of phosphoric acid. Electrolytes → ↑ PTH and ↓ serum calcium Calcium A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes. Electrolytes
  • Urine labs:
    • Urinalysis Urinalysis Examination of urine by chemical, physical, or microscopic means. Routine urinalysis usually includes performing chemical screening tests, determining specific gravity, observing any unusual color or odor, screening for bacteriuria, and examining the sediment microscopically. Urinary Tract Infections (UTIs) in Children with microscopy, findings of CKD include:
    • Spot urine protein-to-creatinine ratio
  • Renal ultrasonography
  • Consider a renal biopsy Renal Biopsy Antineutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis.

Assessing glomerular filtration rate Glomerular filtration rate The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests

The GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests is the volume of plasma Plasma The residual portion of blood that is left after removal of blood cells by centrifugation without prior blood coagulation. Transfusion Products filtered by the glomerulus per unit of time.

  • Normal GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests = 90–120 mL/min:
    • Varies with age, sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria, and muscle mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast
    • Often standardized for body surface area 
    • Is the sum of all filtration rates in all functioning nephrons
  • 24-hour urine collection for creatinine clearance Creatinine clearance Kidney Function Tests:
    • Clinical gold standard for GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests assessment 
    • Can be impractical to obtain
    • Common to have incomplete urine collections that are difficult to interpret
  • eGFR equations using serum creatinine:
    • Most commonly used method to determine GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests for CKD diagnosis 
    • Serum creatinine and GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests have an inverse logarithmic relationship:
      • ↑ in sCr from 1 to 2 = approximately 50% ↓ in GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests
      • ↑ in sCr from 4 to 5 = relatively small ↓ in GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests 
    • Several formulas have been developed and validated:
      • Cockcroft-Gault equation
      • Modification of Diet in Renal Disease (MDRD) equation
      • CKD-EPI equation (most commonly used by nephrologists; the 2021 revised equation no longer includes race and is recommended by the National Kidney Foundation)
    • Input variables: serum creatinine, age, sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria, and race (correlates with muscle mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast)
    • Formulas are accurate only in steady-state conditions (i.e., accurate in CKD but not AKI AKI Acute kidney injury refers to sudden and often reversible loss of renal function, which develops over days or weeks. Azotemia refers to elevated levels of nitrogen-containing substances in the blood that accompany AKI, which include BUN and creatinine. Acute Kidney Injury).
    • Can be inaccurate in setting of low muscle mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast, such as:
      • Malnutrition Malnutrition Malnutrition is a clinical state caused by an imbalance or deficiency of calories and/or micronutrients and macronutrients. The 2 main manifestations of acute severe malnutrition are marasmus (total caloric insufficiency) and kwashiorkor (protein malnutrition with characteristic edema). Malnutrition in children in resource-limited countries
      • Liver Liver The liver is the largest gland in the human body. The liver is found in the superior right quadrant of the abdomen and weighs approximately 1.5 kilograms. Its main functions are detoxification, metabolism, nutrient storage (e.g., iron and vitamins), synthesis of coagulation factors, formation of bile, filtration, and storage of blood. Liver: Anatomy disease
      • Lower-extremity amputation Amputation An amputation is the separation of a portion of the limb or the entire limb from the body, along with the bone. Amputations are generally indicated for conditions that compromise the viability of the limb or promote the spread of a local process that could manifest systemically. Amputation
      • Congenital Congenital Chorioretinitis dwarfism
Relationship between creatinine and gfr

Relationship between creatinine and GFR
eGFR: estimated GFR

Image by Lecturio.

Assessing proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children

  • Urine albumin Albumin Serum albumin from humans. It is an essential carrier of both endogenous substances, such as fatty acids and bilirubin, and of xenobiotics in the blood. Liver Function Tests versus urine protein:
    • Urine protein: all proteins Proteins Linear polypeptides that are synthesized on ribosomes and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of amino acids determines the shape the polypeptide will take, during protein folding, and the function of the protein. Energy Homeostasis lost in the urine:
      • Albumin Albumin Serum albumin from humans. It is an essential carrier of both endogenous substances, such as fatty acids and bilirubin, and of xenobiotics in the blood. Liver Function Tests: normally not filtered or lost in high amounts
      • Smaller proteins Proteins Linear polypeptides that are synthesized on ribosomes and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of amino acids determines the shape the polypeptide will take, during protein folding, and the function of the protein. Energy Homeostasis: may be normally filtered and reabsorbed in the proximal tubule Proximal tubule The renal tubule portion that extends from the bowman capsule in the kidney cortex into the kidney medulla. The proximal tubule consists of a convoluted proximal segment in the cortex, and a distal straight segment descending into the medulla where it forms the u-shaped loop of henle. Tubular System
    • Urine albumin Albumin Serum albumin from humans. It is an essential carrier of both endogenous substances, such as fatty acids and bilirubin, and of xenobiotics in the blood. Liver Function Tests is more sensitive than urine total protein Total protein Liver Function Tests.
  • Proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children thresholds (spot measurements of either urine albumin Albumin Serum albumin from humans. It is an essential carrier of both endogenous substances, such as fatty acids and bilirubin, and of xenobiotics in the blood. Liver Function Tests or urine protein):
  • Methods for assessing proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children:
    • Urine dipstick: provides a semiquantitative measurement only
    • 24-hour urine collection: clinical gold standard, but often impractical
    • Spot urine albumin-to-creatinine ratio or spot urine protein-to-creatinine ratio:
      • Urine albumin Albumin Serum albumin from humans. It is an essential carrier of both endogenous substances, such as fatty acids and bilirubin, and of xenobiotics in the blood. Liver Function Tests (mg) /urine creatinine (g) or urine total protein Total protein Liver Function Tests (mg) /urine creatinine (g)
      • Assumes that 1 g of creatinine is excreted in 24 hours
      • Approximates a 24-hour urine collection
      • Easy to collect (need only 1 random urine sample) → practical way for a clinician Clinician A physician, nurse practitioner, physician assistant, or another health professional who is directly involved in patient care and has a professional relationship with patients. Clinician–Patient Relationship to follow proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children in a patient over time 

Assessing hematuria Hematuria Presence of blood in the urine. Renal Cell Carcinoma

  • Hematuria Hematuria Presence of blood in the urine. Renal Cell Carcinoma may be due to glomerular rather than nonglomerular causes (e.g., a urinary tract Urinary tract The urinary tract is located in the abdomen and pelvis and consists of the kidneys, ureters, urinary bladder, and urethra. The structures permit the excretion of urine from the body. Urine flows from the kidneys through the ureters to the urinary bladder and out through the urethra. Urinary Tract: Anatomy infection, which is unrelated to CKD).
  • Findings on microscopy consistent with glomerular hematuria Hematuria Presence of blood in the urine. Renal Cell Carcinoma:
    • Dysmorphic RBCs RBCs Erythrocytes, or red blood cells (RBCs), are the most abundant cells in the blood. While erythrocytes in the fetus are initially produced in the yolk sac then the liver, the bone marrow eventually becomes the main site of production. Erythrocytes: Histology 
    • RBC casts on microscopy (specific but not sensitive for glomerular disease)

Ultrasound imaging

Sometimes patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with CKD will have a normal GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests, but ultrasound findings will be consistent with CKD. These patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship are at high risk for developing a ↓ GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests if their disease progresses. Ultrasound findings consistent with CKD include:

  • Polycystic kidneys Kidneys The kidneys are a pair of bean-shaped organs located retroperitoneally against the posterior wall of the abdomen on either side of the spine. As part of the urinary tract, the kidneys are responsible for blood filtration and excretion of water-soluble waste in the urine. Kidneys: Anatomy
  • Chronic hydronephrosis Hydronephrosis Hydronephrosis is dilation of the renal collecting system as a result of the obstruction of urine outflow. Hydronephrosis can be unilateral or bilateral. Nephrolithiasis is the most common cause of hydronephrosis in young adults, while prostatic hyperplasia and neoplasm are seen in older patients. Hydronephrosis
  • Small, echogenic kidneys Kidneys The kidneys are a pair of bean-shaped organs located retroperitoneally against the posterior wall of the abdomen on either side of the spine. As part of the urinary tract, the kidneys are responsible for blood filtration and excretion of water-soluble waste in the urine. Kidneys: Anatomy with thin cortices

Renal biopsy Renal Biopsy Antineutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis

  • Indicated when the diagnosis is uncertain
  • Findings in diabetic nephropathy Diabetic nephropathy Kidney injuries associated with diabetes mellitus and affecting kidney glomerulus; arterioles; kidney tubules; and the interstitium. Clinical signs include persistent proteinuria, from microalbuminuria progressing to albuminuria of greater than 300 mg/24 h, leading to reduced glomerular filtration rate and end-stage renal disease. Chronic Diabetic Complications:
    • Mesangial expansion → Kimmelstiel-Wilson nodules
    • Thickening of the glomerular capillary walls and basement membrane Basement membrane A darkly stained mat-like extracellular matrix (ecm) that separates cell layers, such as epithelium from endothelium or a layer of connective tissue. The ecm layer that supports an overlying epithelium or endothelium is called basal lamina. Basement membrane (bm) can be formed by the fusion of either two adjacent basal laminae or a basal lamina with an adjacent reticular lamina of connective tissue. Bm, composed mainly of type IV collagen; glycoprotein laminin; and proteoglycan, provides barriers as well as channels between interacting cell layers. Thin Basement Membrane Nephropathy (TBMN)
    • Glomerulosclerosis
  • Other findings:
    • Sarcoidosis Sarcoidosis Sarcoidosis is a multisystem inflammatory disease that causes noncaseating granulomas. The exact etiology is unknown. Sarcoidosis usually affects the lungs and thoracic lymph nodes, but it can also affect almost every system in the body, including the skin, heart, and eyes, most commonly. Sarcoidosis: noncaseating granulomas Noncaseating granulomas Crohn’s Disease, giant cells Giant cells Multinucleated masses produced by the fusion of many cells; often associated with viral infections. In aids, they are induced when the envelope glycoprotein of the HIV virus binds to the CD4 antigen of uninfected neighboring T4 cells. The resulting syncytium leads to cell death and thus may account for the cytopathic effect of the virus. Giant Cell Arteritis
    • IgA IgA Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory iga is the main immunoglobulin in secretions. Immunoglobulins: Types and Functions nephropathy: mesangial deposits of IgA IgA Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory iga is the main immunoglobulin in secretions. Immunoglobulins: Types and Functions
    • Minimal change disease Minimal change disease Minimal change disease (MCD), also known as lipoid nephrosis, is the most common cause of nephrotic syndrome in children. The designation “minimal change” comes from the very little changes noticed in kidney biopsies under light microscopy. Hallmark clinical findings include edema, proteinuria, hypoalbuminemia, and hyperlipidemia. Minimal Change Disease: podocyte fusion Podocyte Fusion Minimal Change Disease and effacement

Stages of Chronic Kidney Disease

There are 5 stages of CKD; they are classified using GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests and other markers of kidney damage.

  • Stage 1 Stage 1 Trypanosoma brucei/African trypanosomiasis: Normal GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests (≥ 90 mL/min) + other marker of kidney damage; examples include:
    • Proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children with normal GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests (e.g., minimal change disease Minimal change disease Minimal change disease (MCD), also known as lipoid nephrosis, is the most common cause of nephrotic syndrome in children. The designation “minimal change” comes from the very little changes noticed in kidney biopsies under light microscopy. Hallmark clinical findings include edema, proteinuria, hypoalbuminemia, and hyperlipidemia. Minimal Change Disease)
    • Isolated hematuria Hematuria Presence of blood in the urine. Renal Cell Carcinoma with normal GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests (e.g., IgA IgA Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory iga is the main immunoglobulin in secretions. Immunoglobulins: Types and Functions nephropathy)
    • Abnormal imaging with normal GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests (e.g., PKD)
  • Stage 2: mildly decreased GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests (60–89 mL/min) + other marker of kidney damage. Examples are the same as for stage 1 Stage 1 Trypanosoma brucei/African trypanosomiasis, but with a slight ↓ in GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests.
  • Stage 3: moderately decreased GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests (30–59 mL/min):
    • Other markers of kidney damage are not required.
    • Often the stage at which initial nephrology referral is made.
    • Many drugs begin to require dose adjustments at this level.
    • Subdivided into:
      • Stage 3a (45–59 mL/min)
      • Stage 3b (30–44 mL/min): ↑ risk of death from cardiovascular disease
  • Stage 4: severely decreased GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests (15–29 mL/min):
    • Requires close monitoring for signs of uremia Uremia A clinical syndrome associated with the retention of renal waste products or uremic toxins in the blood. It is usually the result of renal insufficiency. Most uremic toxins are end products of protein or nitrogen catabolism, such as urea or creatinine. Severe uremia can lead to multiple organ dysfunctions with a constellation of symptoms. Acute Kidney Injury and volume overload, which would indicate the need for dialysis Dialysis Renal replacement therapy refers to dialysis and/or kidney transplantation. Dialysis is a procedure by which toxins and excess water are removed from the circulation. Hemodialysis and peritoneal dialysis (PD) are the two types of dialysis, and their primary difference is the location of the filtration process (external to the body in hemodialysis versus inside the body for PD). Peritoneal Dialysis and Hemodialysis
    • Stage at which renal replacement therapy begins to be considered:
      • Counseling regarding the likely future need for transplantation and/or dialysis Dialysis Renal replacement therapy refers to dialysis and/or kidney transplantation. Dialysis is a procedure by which toxins and excess water are removed from the circulation. Hemodialysis and peritoneal dialysis (PD) are the two types of dialysis, and their primary difference is the location of the filtration process (external to the body in hemodialysis versus inside the body for PD). Peritoneal Dialysis and Hemodialysis 
      • Referral to transplant center
      • Referral to vascular surgeon for dialysis Dialysis Renal replacement therapy refers to dialysis and/or kidney transplantation. Dialysis is a procedure by which toxins and excess water are removed from the circulation. Hemodialysis and peritoneal dialysis (PD) are the two types of dialysis, and their primary difference is the location of the filtration process (external to the body in hemodialysis versus inside the body for PD). Peritoneal Dialysis and Hemodialysis access procedure
  • Stage 5: ESRD ( GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests < 15 mL/min):
    • All patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship require renal replacement therapy ( dialysis Dialysis Renal replacement therapy refers to dialysis and/or kidney transplantation. Dialysis is a procedure by which toxins and excess water are removed from the circulation. Hemodialysis and peritoneal dialysis (PD) are the two types of dialysis, and their primary difference is the location of the filtration process (external to the body in hemodialysis versus inside the body for PD). Peritoneal Dialysis and Hemodialysis or transplantation).
    • Uremic signs are almost always present.
    • Volume status Volume Status ACES and RUSH: Resuscitation Ultrasound Protocols is difficult to control with diuretics Diuretics Agents that promote the excretion of urine through their effects on kidney function. Heart Failure and Angina Medication alone.
Stages of ckd

Stages of CKD

Image by Lecturio.

Management

Other than specific treatments for certain etiologies, it is important to identify and address risk factors for progression of CKD, to address common complications, and to consider preventive measures needed for patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with decreased GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests.

Risk factors for disease progression

  • Nonmodifiable risk factors:
    • Underlying genetic disease (e.g., PKD)
    • African descent
    • Male sex Sex The totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism. Gender Dysphoria
  • Modifiable risk factors:
    • Proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children > 1 g/day is strongly associated with progression.
    • Hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension
    • Metabolic acidosis Acidosis A pathologic condition of acid accumulation or depletion of base in the body. The two main types are respiratory acidosis and metabolic acidosis, due to metabolic acid build up. Respiratory Acidosis
    • Obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity (↑ glomerular capillary pressure)
    • High-protein diet (↑ glomerular capillary pressure)
    • Smoking Smoking Willful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand. Interstitial Lung Diseases (leads to vascular inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation)

Lifestyle modifications to prevent disease progression

  • Smoking Smoking Willful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand. Interstitial Lung Diseases cessation
  • Dietary changes (assisted by a nutritionist):
    • Low-protein diet:
      • Goal: approximately 0.6–0.8 g/kg/day dietary protein if GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests < 60 mL/min and nonnephrotic
      • Do not restrict intake if nephrotic syndrome Nephrotic syndrome Nephrotic syndrome is characterized by severe proteinuria, hypoalbuminemia, and peripheral edema. In contrast, the nephritic syndromes present with hematuria, variable loss of renal function, and hypertension, although there is sometimes overlap of > 1 glomerular disease in the same individual. Nephrotic Syndrome (> 3.5 g/day proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children) is present.
    • Low-sodium diet (< 2 g of sodium Sodium A member of the alkali group of metals. It has the atomic symbol na, atomic number 11, and atomic weight 23. Hyponatremia/day or 5 g/day of NaCl)
    • Low-phosphorus diet (or take oral phosphorus binders with meals)
  • Exercise
  • Weight loss Weight loss Decrease in existing body weight. Bariatric Surgery

Medical management to prevent disease progression

  • Proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children goal: < 0.5–1 g/day
    • ACE inhibitor or angiotensin receptor Receptor Receptors are proteins located either on the surface of or within a cell that can bind to signaling molecules known as ligands (e.g., hormones) and cause some type of response within the cell. Receptors blockers ( ARBs ARBs Agents that antagonize angiotensin receptors. Many drugs in this class specifically target the angiotensin type 1 receptor. Heart Failure and Angina Medication):
      • Indicated when albuminuria Albuminuria The presence of albumin in the urine, an indicator of kidney diseases. Kidney Function Tests > 30 mg/day or proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children > 150 mg/day
      • Mechanism: vasodilation Vasodilation The physiological widening of blood vessels by relaxing the underlying vascular smooth muscle. Pulmonary Hypertension Drugs of efferent arteriole Efferent arteriole Glomerular Filtration → ↓ glomerular capillary pressure → ↓ hyperfiltration
      • Effect on decreasing proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children is independent of blood pressure effect.
      • Must monitor serum potassium Potassium An element in the alkali group of metals with an atomic symbol k, atomic number 19, and atomic weight 39. 10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the water-electrolyte balance. Hyperkalemia closely.
    • Sodium Sodium A member of the alkali group of metals. It has the atomic symbol na, atomic number 11, and atomic weight 23. Hyponatremia/ glucose Glucose A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement. Lactose Intolerance cotransporter 2 (SGLT2) inhibitors (i.e., dapagliflozin Dapagliflozin Non-insulinotropic Diabetes Drugs):
      • Decrease glomerular hyperfiltration
      • Benefit even in nondiabetics (independent of glucose-lowering effect) 
  • Control metabolic acidosis Acidosis A pathologic condition of acid accumulation or depletion of base in the body. The two main types are respiratory acidosis and metabolic acidosis, due to metabolic acid build up. Respiratory Acidosis bicarbonate Bicarbonate Inorganic salts that contain the -HCO3 radical. They are an important factor in determining the ph of the blood and the concentration of bicarbonate ions is regulated by the kidney. Levels in the blood are an index of the alkali reserve or buffering capacity. Electrolytes supplementation
  • Treat/optimize any underlying medical conditions:
    • Diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus (goal HbA1c HbA1c Products of non-enzymatic reactions between glucose and hemoglobin a, occurring as a minor fraction of the hemoglobin components of human erythrocytes. Hemoglobin a1c is hemoglobin a with glucose covalently bound to the terminal valine of the beta chain. Glycated hemoglobin a is used as an index of the average blood sugar level over a lifetime of erythrocytes. Diabetes Mellitus: < 7%): glycemic control, ACE/ ARBs ARBs Agents that antagonize angiotensin receptors. Many drugs in this class specifically target the angiotensin type 1 receptor. Heart Failure and Angina Medication, weight control
    • Hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension (goal: 125–130/< 80 mm MM Multiple myeloma (MM) is a malignant condition of plasma cells (activated B lymphocytes) primarily seen in the elderly. Monoclonal proliferation of plasma cells results in cytokine-driven osteoclastic activity and excessive secretion of IgG antibodies. Multiple Myeloma Hg): ACE/ ARBs ARBs Agents that antagonize angiotensin receptors. Many drugs in this class specifically target the angiotensin type 1 receptor. Heart Failure and Angina Medication preferred agents
    • Autoimmune disease (e.g., SLE SLE Systemic lupus erythematosus (SLE) is a chronic autoimmune, inflammatory condition that causes immune-complex deposition in organs, resulting in systemic manifestations. Women, particularly those of African American descent, are more commonly affected. Systemic Lupus Erythematosus, Sjögren syndrome Sjögren Syndrome Rheumatoid Arthritis
  • General management:
    • Avoid nephrotoxins (e.g., IV contrast, NSAIDs NSAIDS Primary vs Secondary Headaches).
    • Adjust drug doses for GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests.

Renal replacement therapy

Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with stage V CKD or signs of uremia Uremia A clinical syndrome associated with the retention of renal waste products or uremic toxins in the blood. It is usually the result of renal insufficiency. Most uremic toxins are end products of protein or nitrogen catabolism, such as urea or creatinine. Severe uremia can lead to multiple organ dysfunctions with a constellation of symptoms. Acute Kidney Injury require renal replacement therapy. Options include:

Management of complications

In addition to an overall increase in mortality Mortality All deaths reported in a given population. Measures of Health Status, there are many other complications of CKD.

  • Cardiovascular disease:
    • Reasons to aggressively ↓ cardiovascular disease risk:
      • CKD is an independent risk factor for cardiovascular disease.
      • Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with ≥ stage 3b CKD are more likely to die from cardiovascular disease than from ESRD.
      • Risk of cardiovascular disease is related to both GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests and proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children.
    • Preventive measures include:
      • Statins Statins Statins are competitive inhibitors of HMG-CoA reductase in the liver. HMG-CoA reductase is the rate-limiting step in cholesterol synthesis. Inhibition results in lowered intrahepatocytic cholesterol formation, resulting in up-regulation of LDL receptors and, ultimately, lowering levels of serum LDL and triglycerides. Statins
      • ACE inhibitors ACE inhibitors Truncus Arteriosus
      • Low-dose aspirin Aspirin The prototypical analgesic used in the treatment of mild to moderate pain. It has anti-inflammatory and antipyretic properties and acts as an inhibitor of cyclooxygenase which results in the inhibition of the biosynthesis of prostaglandins. Aspirin also inhibits platelet aggregation and is used in the prevention of arterial and venous thrombosis. Nonsteroidal Antiinflammatory Drugs (NSAIDs)
      • Lifestyle modification (diet, exercise, smoking Smoking Willful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand. Interstitial Lung Diseases cessation)
  • Mineral and bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Bones: Structure and Types disorder:
    • ↓ Phosphorus intake 
    • Oral phosphate Phosphate Inorganic salts of phosphoric acid. Electrolytes binders
    • Calcitriol Calcitriol The physiologically active form of vitamin d. It is formed primarily in the kidney by enzymatic hydroxylation of 25-hydroxycholecalciferol (calcifediol). Its production is stimulated by low blood calcium levels and parathyroid hormone. Calcitriol increases intestinal absorption of calcium and phosphorus, and in concert with parathyroid hormone increases bone resorption. Parathyroid Glands: Anatomy supplementation
    • Cinacalcet Cinacalcet Calcimimetics
  • Anemia Anemia Anemia is a condition in which individuals have low Hb levels, which can arise from various causes. Anemia is accompanied by a reduced number of RBCs and may manifest with fatigue, shortness of breath, pallor, and weakness. Subtypes are classified by the size of RBCs, chronicity, and etiology. Anemia: Overview and Types:
  • Hypervolemia Hypervolemia Renal Sodium and Water Regulation:
  • Hyperkalemia Hyperkalemia Hyperkalemia is defined as a serum potassium (K+) concentration >5.2 mEq/L. Homeostatic mechanisms maintain the serum K+ concentration between 3.5 and 5.2 mEq/L, despite marked variation in dietary intake. Hyperkalemia can be due to a variety of causes, which include transcellular shifts, tissue breakdown, inadequate renal excretion, and drugs. Hyperkalemia:
    • Dietary potassium Potassium An element in the alkali group of metals with an atomic symbol k, atomic number 19, and atomic weight 39. 10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the water-electrolyte balance. Hyperkalemia restriction 
    • Loop diuretics Diuretics Agents that promote the excretion of urine through their effects on kidney function. Heart Failure and Angina Medication
    • Oral potassium-binding resins (e.g., patiromer) 
    • Consider discontinuing ACE inhibitors ACE inhibitors Truncus Arteriosus/ ARBs ARBs Agents that antagonize angiotensin receptors. Many drugs in this class specifically target the angiotensin type 1 receptor. Heart Failure and Angina Medication as CKD progresses.

Differential Diagnosis

  • Diabetic nephropathy Diabetic nephropathy Kidney injuries associated with diabetes mellitus and affecting kidney glomerulus; arterioles; kidney tubules; and the interstitium. Clinical signs include persistent proteinuria, from microalbuminuria progressing to albuminuria of greater than 300 mg/24 h, leading to reduced glomerular filtration rate and end-stage renal disease. Chronic Diabetic Complications: most common cause of ESRD (approximately 55% of all new dialysis Dialysis Renal replacement therapy refers to dialysis and/or kidney transplantation. Dialysis is a procedure by which toxins and excess water are removed from the circulation. Hemodialysis and peritoneal dialysis (PD) are the two types of dialysis, and their primary difference is the location of the filtration process (external to the body in hemodialysis versus inside the body for PD). Peritoneal Dialysis and Hemodialysis patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship). Some stage of CKD will develop in 20%–30% of all diabetics. The pathophysiology is multifactorial and involves glomerular capillary hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension, which leads to albuminuria Albuminuria The presence of albumin in the urine, an indicator of kidney diseases. Kidney Function Tests and progressive loss of GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests. Kidney biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma characteristically shows Kimmelstiel-Wilson nodules. Treatment involves glycemic control and ACEis ACEIs A class of drugs whose main indications are the treatment of hypertension and heart failure. They exert their hemodynamic effect mainly by inhibiting the renin-angiotensin system. They also modulate sympathetic nervous system activity and increase prostaglandin synthesis. They cause mainly vasodilation and mild natriuresis without affecting heart rate and contractility. Heart Failure and Angina Medication.
  • Hypertensive nephrosclerosis Nephrosclerosis Hardening of the kidney due to infiltration by fibrous connective tissue (fibrosis), usually caused by renovascular diseases or chronic hypertension. Nephrosclerosis leads to renal ischemia. Liddle Syndrome: CKD caused primarily by long-standing hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension. Hypertensive nephrosclerosis Nephrosclerosis Hardening of the kidney due to infiltration by fibrous connective tissue (fibrosis), usually caused by renovascular diseases or chronic hypertension. Nephrosclerosis leads to renal ischemia. Liddle Syndrome is the second most common cause of renal failure Renal failure Conditions in which the kidneys perform below the normal level in the ability to remove wastes, concentrate urine, and maintain electrolyte balance; blood pressure; and calcium metabolism. Renal insufficiency can be classified by the degree of kidney damage (as measured by the level of proteinuria) and reduction in glomerular filtration rate. Crush Syndrome in dialysis Dialysis Renal replacement therapy refers to dialysis and/or kidney transplantation. Dialysis is a procedure by which toxins and excess water are removed from the circulation. Hemodialysis and peritoneal dialysis (PD) are the two types of dialysis, and their primary difference is the location of the filtration process (external to the body in hemodialysis versus inside the body for PD). Peritoneal Dialysis and Hemodialysis patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship in the United States. Clinical presentation is usually asymptomatic, other than the blood pressure findings. Hypertensive nephrosclerosis Nephrosclerosis Hardening of the kidney due to infiltration by fibrous connective tissue (fibrosis), usually caused by renovascular diseases or chronic hypertension. Nephrosclerosis leads to renal ischemia. Liddle Syndrome is often a diagnosis of exclusion in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with minimal proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children (< 1 g/day), no glomerular hematuria Hematuria Presence of blood in the urine. Renal Cell Carcinoma on urinalysis Urinalysis Examination of urine by chemical, physical, or microscopic means. Routine urinalysis usually includes performing chemical screening tests, determining specific gravity, observing any unusual color or odor, screening for bacteriuria, and examining the sediment microscopically. Urinary Tract Infections (UTIs) in Children, and no findings of other systemic diseases. Management is aimed at blood pressure control and addressing the other complications and risk factors common to all etiologies of CKD.
  • Polycystic kidney disease: Autosomal dominant Autosomal dominant Autosomal inheritance, both dominant and recessive, refers to the transmission of genes from the 22 autosomal chromosomes. Autosomal dominant diseases are expressed when only 1 copy of the dominant allele is inherited. Autosomal Recessive and Autosomal Dominant Inheritance PKD is the most common genetic cause of kidney disease in adults and is characterized by the progressive development of cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change in the kidneys Kidneys The kidneys are a pair of bean-shaped organs located retroperitoneally against the posterior wall of the abdomen on either side of the spine. As part of the urinary tract, the kidneys are responsible for blood filtration and excretion of water-soluble waste in the urine. Kidneys: Anatomy. Eventually, the burden of cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change results in the loss of nephrons and in GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests. Signs and symptoms include abdominal fullness, easily palpable kidneys Kidneys The kidneys are a pair of bean-shaped organs located retroperitoneally against the posterior wall of the abdomen on either side of the spine. As part of the urinary tract, the kidneys are responsible for blood filtration and excretion of water-soluble waste in the urine. Kidneys: Anatomy, hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension, hematuria Hematuria Presence of blood in the urine. Renal Cell Carcinoma, and recurrent infections Recurrent infections Common Variable Immunodeficiency (CVID) of the cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change. Diagnosis is mainly by imaging, and cysts Cysts Any fluid-filled closed cavity or sac that is lined by an epithelium. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues. Fibrocystic Change are often also present in the liver Liver The liver is the largest gland in the human body. The liver is found in the superior right quadrant of the abdomen and weighs approximately 1.5 kilograms. Its main functions are detoxification, metabolism, nutrient storage (e.g., iron and vitamins), synthesis of coagulation factors, formation of bile, filtration, and storage of blood. Liver: Anatomy. PKD also has a significant association with cerebral aneurysms. Management is primarily supportive, and CKD can progress to ESRD.
  • Reflux nephropathy Reflux nephropathy Vesicoureteral Reflux: also known as vesicoureteral reflux Vesicoureteral Reflux Vesicoureteral reflux (VUR) is the retrograde flow of urine from the bladder into the upper urinary tract. Primary VUR often results from the incomplete closure of the ureterovesical junction, whereas secondary VUR is due to an anatomic or physiologic obstruction. Vesicoureteral Reflux. Reflux nephropathy Reflux nephropathy Vesicoureteral Reflux usually presents in childhood and is characterized by the retrograde flow Retrograde flow Veins: Histology of urine into the kidneys Kidneys The kidneys are a pair of bean-shaped organs located retroperitoneally against the posterior wall of the abdomen on either side of the spine. As part of the urinary tract, the kidneys are responsible for blood filtration and excretion of water-soluble waste in the urine. Kidneys: Anatomy due to inadequate closure at the ureterovesicular junction Ureterovesicular junction Urinary Tract: Anatomy. This retrograde flow Retrograde flow Veins: Histology results in tubulointerstitial damage, chronic kidney disease, and the predisposition to recurrent urinary tract Urinary tract The urinary tract is located in the abdomen and pelvis and consists of the kidneys, ureters, urinary bladder, and urethra. The structures permit the excretion of urine from the body. Urine flows from the kidneys through the ureters to the urinary bladder and out through the urethra. Urinary Tract: Anatomy infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease. Diagnosis is by contrast voiding cystourethrography, and treatment includes prophylactic antibiotics and endoscopic or surgical correction.
  • Atherosclerotic CKD ( renal artery Renal artery A branch of the abdominal aorta which supplies the kidneys, adrenal glands and ureters. Glomerular Filtration stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS)): also known as ischemic nephropathy. CKD occurs only with bilateral stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS) of > 70%, as lesser degrees of stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS), or stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS) to only 1 of 2 functioning kidneys Kidneys The kidneys are a pair of bean-shaped organs located retroperitoneally against the posterior wall of the abdomen on either side of the spine. As part of the urinary tract, the kidneys are responsible for blood filtration and excretion of water-soluble waste in the urine. Kidneys: Anatomy, will be compensated for. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship may present with refractory hypertension Refractory hypertension Blood pressure that cannot be controlled even with maximally tolerated doses of ≥ 5 drugs. Uncontrolled Hypertension and often have atherosclerosis Atherosclerosis Atherosclerosis is a common form of arterial disease in which lipid deposition forms a plaque in the blood vessel walls. Atherosclerosis is an incurable disease, for which there are clearly defined risk factors that often can be reduced through a change in lifestyle and behavior of the patient. Atherosclerosis elsewhere (e.g., coronary artery Coronary Artery Truncus Arteriosus disease and/or peripheral artery disease Peripheral artery disease Peripheral artery disease (PAD) is obstruction of the arterial lumen resulting in decreased blood flow to the distal limbs. The disease can be a result of atherosclerosis or thrombosis. Patients may be asymptomatic or have progressive claudication, skin discoloration, ischemic ulcers, or gangrene. Peripheral Artery Disease) and other general risk factors for vascular disease (i.e., hyperlipidemia and smoking Smoking Willful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand. Interstitial Lung Diseases). Management involves blood pressure control and risk reduction.
  • Obstructive uropathy: CKD from chronic obstruction of the urinary tract Urinary tract The urinary tract is located in the abdomen and pelvis and consists of the kidneys, ureters, urinary bladder, and urethra. The structures permit the excretion of urine from the body. Urine flows from the kidneys through the ureters to the urinary bladder and out through the urethra. Urinary Tract: Anatomy. Obstructive uropathy may be due to BPH BPH Benign prostatic hyperplasia (bph) is a condition indicating an increase in the number of stromal and epithelial cells within the prostate gland (transition zone). Benign prostatic hyperplasia is common in men > 50 years of age and may greatly affect their quality of life. Benign Prostatic Hyperplasia, urethral stricture Stricture Primary Sclerosing Cholangitis, bilateral obstructing kidney stones Kidney stones Nephrolithiasis is the formation of a stone, or calculus, anywhere along the urinary tract caused by precipitations of solutes in the urine. The most common type of kidney stone is the calcium oxalate stone, but other types include calcium phosphate, struvite (ammonium magnesium phosphate), uric acid, and cystine stones. Nephrolithiasis, or a pelvic mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast. For a rise in serum creatinine to develop, there must be bilateral obstruction, which is most commonly due to BPH BPH Benign prostatic hyperplasia (bph) is a condition indicating an increase in the number of stromal and epithelial cells within the prostate gland (transition zone). Benign prostatic hyperplasia is common in men > 50 years of age and may greatly affect their quality of life. Benign Prostatic Hyperplasia in men and to gynecologic pelvic masses in women. Treatment involves relief of the obstruction, which may require surgical intervention, depending on the etiology.
  • Nephrotic syndrome Nephrotic syndrome Nephrotic syndrome is characterized by severe proteinuria, hypoalbuminemia, and peripheral edema. In contrast, the nephritic syndromes present with hematuria, variable loss of renal function, and hypertension, although there is sometimes overlap of > 1 glomerular disease in the same individual. Nephrotic Syndrome: broad category of kidney diseases characterized by very large amounts of proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children (> 3.5 g/day). Diseases of this category include focal segmental glomerulosclerosis, membranous nephropathy, minimal change disease Minimal change disease Minimal change disease (MCD), also known as lipoid nephrosis, is the most common cause of nephrotic syndrome in children. The designation “minimal change” comes from the very little changes noticed in kidney biopsies under light microscopy. Hallmark clinical findings include edema, proteinuria, hypoalbuminemia, and hyperlipidemia. Minimal Change Disease, and membranoproliferative glomerulonephritis Membranoproliferative Glomerulonephritis Membranoproliferative glomerulonephritis (MPGN) is also known as mesangiocapillary glomerulonephritis. Membranoproliferative glomerulonephritis is a pattern of glomerular injury characterized by mesangial hypercellularity, endocapillary proliferation, and thickening of the glomerular basement membrane (double contour formation). Membranoproliferative Glomerulonephritis. The clinical presentation of nephrotic syndrome Nephrotic syndrome Nephrotic syndrome is characterized by severe proteinuria, hypoalbuminemia, and peripheral edema. In contrast, the nephritic syndromes present with hematuria, variable loss of renal function, and hypertension, although there is sometimes overlap of > 1 glomerular disease in the same individual. Nephrotic Syndrome is notable for volume overload (including periorbital Periorbital Orbital and Preseptal Cellulitis edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema) and “frothy urine” due to severe proteinuria Proteinuria The presence of proteins in the urine, an indicator of kidney diseases. Nephrotic Syndrome in Children. Treatment varies by etiology and often includes glucocorticoids Glucocorticoids Glucocorticoids are a class within the corticosteroid family. Glucocorticoids are chemically and functionally similar to endogenous cortisol. There are a wide array of indications, which primarily benefit from the antiinflammatory and immunosuppressive effects of this class of drugs. Glucocorticoids.
  • Nephritic syndrome Nephritic syndrome Nephritic syndrome is a broad category of glomerular diseases characterized by glomerular hematuria, variable loss of renal function, and hypertension. These features are in contrast to those of nephrotic syndrome, which includes glomerular diseases characterized by severe proteinuria, although there is sometimes overlap of > 1 glomerular disease in the same individual. Nephritic Syndrome: broad category of kidney diseases characterized by glomerular hematuria Hematuria Presence of blood in the urine. Renal Cell Carcinoma and loss of GFR GFR The volume of water filtered out of plasma through glomerular capillary walls into Bowman’s capsules per unit of time. It is considered to be equivalent to inulin clearance. Kidney Function Tests. Diseases of this category include IgA IgA Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory iga is the main immunoglobulin in secretions. Immunoglobulins: Types and Functions nephropathy, lupus nephritis Lupus nephritis Glomerulonephritis associated with autoimmune disease systemic lupus erythematosus. Lupus nephritis is histologically classified into 6 classes: class I – normal glomeruli, class II – pure mesangial alterations, class III – focal segmental glomerulonephritis, class IV – diffuse glomerulonephritis, class V – diffuse membranous glomerulonephritis, and class VI – advanced sclerosing glomerulonephritis (the world health organization classification 1982). Diffuse Proliferative Glomerulonephritis, postinfectious glomerulonephritis, and many others. Clinical presentation and management vary significantly, depending on etiology.

References

  1. Cheung, A. K., Kronenberg, F. (2020). Lipid management in patients with nondialysis chronic kidney disease. UpToDate. Retrieved April 21, 2021, from https://www.uptodate.com/contents/lipid-management-in-patients-with-nondialysis-chronic-kidney-disease
  2. Cho, M. E., Srinivasan, B. (2020). Dietary recommendations for patients with nondialysis chronic kidney disease. UpToDate. Retrieved April 24, 2021, from https://www.uptodate.com/contents/dietary-recommendations-for-patients-with-nondialysis-chronic-kidney-disease
  3. Delmez, J. A., Slatopolsky, E. (1992). Hyperphosphatemia: its consequences and treatment in patients with chronic renal disease. American Journal of Kidney Diseases 19:303–317. https://doi.org/10.1016/s0272-6386(12)80446-x
  4. Fatehi, P., Chi-yuan, H. (2020). Chronic kidney disease (newly identified): clinical presentation and diagnostic approach in adults. UpToDate. Retrieved April 21, 2021, from https://www.uptodate.com/contents/chronic-kidney-disease-newly-identified-clinical-presentation-and-diagnostic-approach-in-adults
  5. Hill, N. R., et al. (2016). Global prevalence of chronic kidney disease – a systematic review and meta-analysis. PLoS ONE 11(7). https://doi.org/10.1371/journal.pone.0158765
  6. Hou, S. (1985). Pregnancy in women with chronic renal disease. New England Journal of Medicine 312:836–839. https://doi.org/10.1056/NEJM198503283121306
  7. National Kidney Foundation (K/DOQI). (2000). Nutrition in Chronic renal failure guidelines: dietary energy intake (DEI) for nondialyzed patients. American Journal of Kidney Diseases 35(6):1–140. https://www.kidney.org/sites/default/files/docs/kdoqi2000nutritiongl.pdf 
  8. Levin, A., et al. (2013). Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2012 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney International Supplements. 3(1):1–150. https://jhu.pure.elsevier.com/en/publications/kidney-disease-improving-global-outcomes-kdigo-ckd-work-group-kdi-4
  9. Kidney Disease Outcomes Quality Initiative (K/DOQI). (2004). K/DOQI clinical practice guidelines on hypertension and antihypertensive agents in chronic kidney disease. American Journal of Kidney Diseases 43(5 Suppl 1):1–290. https://pubmed.ncbi.nlm.nih.gov/15114537/
  10. Levey, A. S., Inker, L. A. (2020). Definition and staging of chronic kidney disease in adults. UpToDate. Retrieved April 21, 2021, from https://www.uptodate.com/contents/definition-and-staging-of-chronic-kidney-disease-in-adults
  11. Liyanage, T., et al. (2015). Worldwide access to treatment for end-stage kidney disease: a systematic review. Lancet 385:1975–1982. https://doi.org/10.1016/S0140-6736(14)61601-9
  12. Mann, J. F. E., Bakris G. L. (2019). Antihypertensive therapy and progression of nondiabetic chronic kidney disease in adults. UpToDate. Retrieved April 24, 2021, from https://www.uptodate.com/contents/antihypertensive-therapy-and-progression-of-nondiabetic-chronic-kidney-disease-in-adults
  13. Mattoo, T. K., Greenfield, S. P. (2021). Clinical presentation, diagnosis, and course of primary vesicoureteral reflux. UpToDate. Retrieved April 24, 2021, from https://www.uptodate.com/contents/clinical-presentation-diagnosis-and-course-of-primary-vesicoureteral-reflux
  14. Mattoo, T. K., Greenfield, S. P. (2021). Management of vesicoureteral reflux. UpToDate. Retrieved April 24, 2021, from https://www.uptodate.com/contents/management-of-vesicoureteral-reflux
  15. Mills, K. T., et al. (2015). A systematic analysis of worldwide population-based data on the global burden of chronic kidney disease in 2010. Kidney International 88:950–957. https://doi.org/10.1038/ki.2015.230
  16. Obrador, G. T. (2020). Epidemiology of chronic kidney disease. UpToDate. Retrieved April 21, 2021, from https://www.uptodate.com/contents/epidemiology-of-chronic-kidney-disease
  17. Rosenberg, M. (2020). Overview of the management of chronic kidney disease in adults. UpToDate. Retrieved April 21, 2021, from https://www.uptodate.com/contents/overview-of-the-management-of-chronic-kidney-disease-in-adults
  18. Saardi, K. M., Schwartz, R. A. (2016). Uremic frost: A harbinger of impending renal failure. International Journal of Dermatology. 55(1), 17–20. https://doi.org/https://doi.org/10.1111/ijd.12963
  19. Sarnak, M., et al. (2019). Chronic kidney disease and coronary heart disease. UpToDate. Retrieved April 21, 2021, from https://www.uptodate.com/contents/chronic-kidney-disease-and-coronary-heart-disease
  20. Textor, S. (2020). Clinical manifestations and diagnosis of chronic kidney disease resulting from atherosclerotic renal artery stenosis. UpToDate. Retrieved April 23, 2021, from https://www.uptodate.com/contents/clinical-manifestations-and-diagnosis-of-chronic-kidney-disease-resulting-from-atherosclerotic-renal-artery-stenosis 
  21. Thomas, B., et al. (2017). Global cardiovascular and renal outcomes of reduced GFR. Journal of the American Society of Nephrology 28:2167–2179. https://doi.org/10.1681/ASN.2016050562
  22. Townsend, R.R. (2020). Major side effects of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers. UpToDate. Retrieved April 24, 2021, from https://www.uptodate.com/contents/major-side-effects-of-angiotensin-converting-enzyme-inhibitors-and-angiotensin-ii-receptor-blockers
  23. Prasad, P., Ingerowski, E. (2020). Chronic kidney disease. VisualDx. Retrieved April 21, 2021, from https://www.visualdx.com/visualdx/diagnosis/chronic+kidney+disease?diagnosisId=54724&moduleId=101
  24. Ralston, S.H., Penman, I.D., et al. (Eds.). Davidson’s Principles and Practice of Medicine, 23rd ed., pp. 415–419.

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