Chronic kidney disease (CKD) is kidney impairment that lasts for ≥ 3 months, implying that it is irreversible. HypertensionHypertensionHypertension, 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 diabetesDiabetesDiabetes 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 dialysisDialysisRenal 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.
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:
↓ GFRGFRThe 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 patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship can have a normal GFRGFRThe 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.)
Pathologic findings on kidney biopsyBiopsyRemoval and pathologic examination of specimens from the living body.Ewing Sarcoma
Epidemiology
PrevalencePrevalenceThe 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 prevalencePrevalenceThe 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
MortalityMortalityAll deaths reported in a given population.Measures of Health Status: approximately 66% after 5 years on dialysisDialysisRenal 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
SexSexThe 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 resistanceResistancePhysiologically, 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 AKIAKIAcute 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. DiabetesDiabetesDiabetes 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 hypertensionHypertensionHypertension, 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
Hypertensive nephrosclerosisNephrosclerosisHardening 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
Atheroembolic disease → cholesterolCholesterolThe 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
Glomerular disease
Diabetic nephropathyDiabetic nephropathyKidney 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:
IgAIgARepresents 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 nephritisLupus nephritisGlomerulonephritis 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 erythematosusSystemic lupus erythematosusSystemic 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 (SLESLESystemic 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):
Autosomal dominantAutosomal dominantAutosomal 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 presents in adults
Autosomal recessiveAutosomal recessiveAutosomal inheritance, both dominant and recessive, refers to the transmission of genes from the 22 autosomal chromosomes. Autosomal recessive diseases are only expressed when 2 copies of the recessive allele are inherited.Autosomal Recessive and Autosomal Dominant Inheritance PKD presents in children
SarcoidosisSarcoidosisSarcoidosis 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., NSAIDNSAIDNonsteroidal 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 refluxVesicoureteral RefluxVesicoureteral 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
BenignBenignFibroadenoma prostatic hyperplasiaHyperplasiaAn 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 (BPHBPHBenign 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)
Bilateral obstructing kidney stonesKidney stonesNephrolithiasis 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 massMassThree-dimensional lesion that occupies a space within the breastImaging of the Breast
Other causes
AKIAKIAcute 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
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 (nephronNephronThe functional units of the kidney, consisting of the glomerulus and the attached tubule.Kidneys: AnatomymassMassThree-dimensional lesion that occupies a space within the breastImaging of the Breast), which leads to:
↑ Glomerular permeability → ↑ filtration of proteinsProteinsLinear 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., proteinuriaProteinuriaThe presence of proteins in the urine, an indicator of kidney diseases.Nephrotic Syndrome in Children)
Activation of the RAASRAASA 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:
GFRGFRThe 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 hypertensionHypertensionHypertension, 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.
Common pathogenesis of CKD, independent of initial etiology
Image by Lecturio.
Pathogenesis of hypertensionHypertensionHypertension, 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
HypertensionHypertensionHypertension, 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
↑ RAASRAASA 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 systemNervous systemThe 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
VasoconstrictionVasoconstrictionThe physiological narrowing of blood vessels by contraction of the vascular smooth muscle.Vascular Resistance, Flow, and Mean Arterial Pressure from ↑ CaCACondylomata 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 hyperparathyroidismSecondary hyperparathyroidismAbnormally 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 oxideNitric OxideA 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 vasodilationVasodilationThe physiological widening of blood vessels by relaxing the underlying vascular smooth muscle.Pulmonary Hypertension Drugs)
Pathogenesis of secondary hyperparathyroidismSecondary hyperparathyroidismAbnormally 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 hyperparathyroidismSecondary hyperparathyroidismAbnormally 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 boneBoneBone 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.
↓ GFRGFRThe 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 phosphatePhosphateInorganic salts of phosphoric acid.Electrolytes excretion → ↑ serum phosphatePhosphateInorganic salts of phosphoric acid.Electrolytes (PO43–) → ↑ fibroblast growth factorFibroblast growth factorA 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 ↑ parathyroidParathyroidThe 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) secretionSecretionCoagulation Studies (i.e., secondary hyperparathyroidismSecondary hyperparathyroidismAbnormally 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 (calcitriolCalcitriolThe 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)
↓ CalcitriolCalcitriolThe 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 CaCACondylomata 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+absorptionAbsorptionAbsorption 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 CaCACondylomata 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 hyperparathyroidismSecondary hyperparathyroidismAbnormally 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 (↑ morbidityMorbidityThe proportion of patients with a particular disease during a given year per given unit of population.Measures of Health Status from cardiovascular disease)
Renal osteodystrophyOsteodystrophyCirrhosis (↑ morbidityMorbidityThe 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:
OsteomalaciaOsteomalaciaDisorder 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 boneBoneBone 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 boneBoneBone 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 (osteomalaciaOsteomalaciaDisorder 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 boneBoneBone 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 (iatrogenicIatrogenicAny 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 FGF-23: fibroblast growth factor 23
Image by Lecturio.
Pathophysiology of anemiaAnemiaAnemia 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 erythropoietinErythropoietinGlycoprotein 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 RBCsRBCsErythrocytes, 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
Often, CKD disease remains asymptomatic until the late stages, despite a significant decrease in GFRGFRThe 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.
HematuriaHematuriaPresence of blood in the urine.Renal Cell Carcinoma and/or proteinuriaProteinuriaThe presence of proteins in the urine, an indicator of kidney diseases.Nephrotic Syndrome in Children found on urinalysisUrinalysisExamination 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 tractUrinary tractThe 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)
HypertensionHypertensionHypertension, 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% prevalencePrevalenceThe 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 edemaEdemaEdema 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
AscitesAscitesAscites 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 uremiaUremiaA 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:
NauseaNauseaAn 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, vomitingVomitingThe forcible expulsion of the contents of the stomach through the mouth.Hypokalemia, and anorexiaAnorexiaThe 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
Friction rub on cardiac auscultation (sign of pericardial effusionPericardial effusionFluid 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)
SkinSkinThe 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 FunctionsexcoriationsExcoriationsExcoriation 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 pruritusPruritusAn intense itching sensation that produces the urge to rub or scratch the skin to obtain relief.Atopic Dermatitis (Eczema)
Uremic frost (ureaUreaA 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 skinSkinThe 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:
RetinopathyRetinopathyDegenerative changes to the retina due to hypertension.Alport Syndrome (hypertensive nephrosclerosisNephrosclerosisHardening 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, diabetesDiabetesDiabetes 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)
Livedo reticularis rashRashRocky Mountain Spotted Fever, particularly on the toes (cholesterolCholesterolThe 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 kidneysKidneysThe 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)
PeriorbitalPeriorbitalOrbital and Preseptal CellulitisedemaEdemaEdema 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 syndromeNephrotic syndromeNephrotic 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 hematuriaHematuriaPresence of blood in the urine.Renal Cell Carcinoma (IgAIgARepresents 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 diseasesAutoimmune diseasesDisorders 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 rashMalar RashSystemic Lupus Erythematosus in SLESLESystemic 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 painPainAn unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons.Pain: Types and Pathways, dyspneaDyspneaDyspnea 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 boneBoneBone 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 hyperparathyroidismSecondary hyperparathyroidismAbnormally 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): boneBoneBone 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 TypespainPainAn unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons.Pain: Types and Pathways, fractures
AnemiaAnemiaAnemia 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: fatigueFatigueThe 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, dyspneaDyspneaDyspnea 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
HyperkalemiaHyperkalemiaHyperkalemia 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
The initial diagnosis of CKD is by finding a decreased GFRGFRThe 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, hematuriaHematuriaPresence of blood in the urine.Renal Cell Carcinoma, proteinuriaProteinuriaThe 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 GFRGFRThe 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 diabetesDiabetesDiabetes 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:
AnemiaAnemiaAnemia 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 patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship with a GFRGFRThe 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)
HyperkalemiaHyperkalemiaHyperkalemia 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 acidosisAcidosisA 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 hyperparathyroidismSecondary hyperparathyroidismAbnormally 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 phosphatePhosphateInorganic salts of phosphoric acid.Electrolytes → ↑ PTH and ↓ serum calciumCalciumA 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:
UrinalysisUrinalysisExamination 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:
Assessing glomerular filtration rateGlomerular filtration rateThe 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 GFRGFRThe 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 plasmaPlasmaThe 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 GFRGFRThe 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, sexSexThe totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism.Gender Dysphoria, and muscle massMassThree-dimensional lesion that occupies a space within the breastImaging of the Breast
Often standardized for body surface area
Is the sum of all filtration rates in all functioning nephrons
Clinical gold standard for GFRGFRThe 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 GFRGFRThe 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 GFRGFRThe 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 GFRGFRThe 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 GFRGFRThe 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, sexSexThe totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism.Gender Dysphoria, and race (correlates with muscle massMassThree-dimensional lesion that occupies a space within the breastImaging of the Breast)
Formulas are accurate only in steady-state conditions (i.e., accurate in CKD but not AKIAKIAcute 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 massMassThree-dimensional lesion that occupies a space within the breastImaging of the Breast, such as:
MalnutritionMalnutritionMalnutrition 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
LiverLiverThe 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 amputationAmputationAn 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
Urine albuminAlbuminSerum 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 proteinsProteinsLinear 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:
AlbuminAlbuminSerum 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 proteinsProteinsLinear 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 tubuleProximal tubuleThe 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 albuminAlbuminSerum 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 proteinTotal proteinLiver Function Tests.
ProteinuriaProteinuriaThe presence of proteins in the urine, an indicator of kidney diseases.Nephrotic Syndrome in Children thresholds (spot measurements of either urine albuminAlbuminSerum 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):
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 albuminAlbuminSerum 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 proteinTotal proteinLiver 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 clinicianClinicianA 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 proteinuriaProteinuriaThe presence of proteins in the urine, an indicator of kidney diseases.Nephrotic Syndrome in Children in a patient over time
HematuriaHematuriaPresence of blood in the urine.Renal Cell Carcinoma may be due to glomerular rather than nonglomerular causes (e.g., a urinary tractUrinary tractThe 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 hematuriaHematuriaPresence of blood in the urine.Renal Cell Carcinoma:
Dysmorphic RBCsRBCsErythrocytes, 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 patientsPatientsIndividuals 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 GFRGFRThe 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 patientsPatientsIndividuals 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 ↓ GFRGFRThe 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 kidneysKidneysThe 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 hydronephrosisHydronephrosisHydronephrosis 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 kidneysKidneysThe 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
Hydronephrosis on renal ultrasound
Image: “Hydro” by morning2k. License: CC BY-SA 3.0, edited by Lecturio.
Small kidney with a thin cortex
Image: “Ultrasonography of chronic renal disease caused by glomerulonephritis” by Kristoffer Lindskov Hansen, Michael Bachmann Nielsen and Caroline Ewertsen. License: CC BY 4.0, edited by Lecturio.
Findings in diabetic nephropathyDiabetic nephropathyKidney 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 membraneBasement membraneA 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:
SarcoidosisSarcoidosisSarcoidosis 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 granulomasNoncaseating granulomasCrohn’s Disease, giant cellsGiant cellsMultinucleated 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
IgAIgARepresents 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 IgAIgARepresents 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 diseaseMinimal change diseaseMinimal 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 fusionPodocyte FusionMinimal Change Disease and effacement
Renal biopsy findings consistent with sarcoidosis
Image: “Sarcoidosis in Native and Transplanted Kidneys: Incidence, Pathologic Findings, and Clinical Course” by Serena M. Bagnasco, et al. License: CC BY 4.0, edited by Lecturio.
IgA nephropathy:
Immunofluorescence demonstrating positivity for IgA
Image: “IgA Nephropathy in a Patient Presenting with Pseudotumor Cerebri” by Ahmed US, Bacaj P, Iqbal HI, Onder S. License: CC BY 4.0
There are 5 stages of CKD; they are classified using GFRGFRThe 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 1Stage 1Trypanosoma brucei/African trypanosomiasis: Normal GFRGFRThe 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:
ProteinuriaProteinuriaThe presence of proteins in the urine, an indicator of kidney diseases.Nephrotic Syndrome in Children with normal GFRGFRThe 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 diseaseMinimal change diseaseMinimal 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 hematuriaHematuriaPresence of blood in the urine.Renal Cell Carcinoma with normal GFRGFRThe 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., IgAIgARepresents 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 GFRGFRThe 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 GFRGFRThe 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 1Stage 1Trypanosoma brucei/African trypanosomiasis, but with a slight ↓ in GFRGFRThe 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 GFRGFRThe 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 GFRGFRThe 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 uremiaUremiaA 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 dialysisDialysisRenal 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 dialysisDialysisRenal 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 dialysisDialysisRenal 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 (GFRGFRThe 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 patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship require renal replacement therapy (dialysisDialysisRenal 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).
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 patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship with decreased GFRGFRThe 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 sexSexThe totality of characteristics of reproductive structure, functions, phenotype, and genotype, differentiating the male from the female organism.Gender Dysphoria
Modifiable risk factors:
ProteinuriaProteinuriaThe presence of proteins in the urine, an indicator of kidney diseases.Nephrotic Syndrome in Children > 1 g/day is strongly associated with progression.
HypertensionHypertensionHypertension, 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 acidosisAcidosisA 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
ObesityObesityObesity 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)
SmokingSmokingWillful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand.Interstitial Lung Diseases (leads to vascular inflammationInflammationInflammation 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
SmokingSmokingWillful 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 GFRGFRThe 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 syndromeNephrotic syndromeNephrotic 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 proteinuriaProteinuriaThe presence of proteins in the urine, an indicator of kidney diseases.Nephrotic Syndrome in Children) is present.
Low-sodium diet (< 2 g of sodiumSodiumA 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)
ACE inhibitor or angiotensin receptorReceptorReceptors 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 (ARBsARBsAgents that antagonize angiotensin receptors. Many drugs in this class specifically target the angiotensin type 1 receptor.Heart Failure and Angina Medication):
Effect on decreasing proteinuriaProteinuriaThe presence of proteins in the urine, an indicator of kidney diseases.Nephrotic Syndrome in Children is independent of blood pressure effect.
Must monitor serum potassiumPotassiumAn 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.
SodiumSodiumA member of the alkali group of metals. It has the atomic symbol na, atomic number 11, and atomic weight 23.Hyponatremia/glucoseGlucoseA 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., dapagliflozinDapagliflozinNon-insulinotropic Diabetes Drugs):
Decrease glomerular hyperfiltration
Benefit even in nondiabetics (independent of glucose-lowering effect)
Control metabolic acidosisAcidosisA 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: bicarbonateBicarbonateInorganic 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:
DiabetesDiabetesDiabetes 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 HbA1cHbA1cProducts 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/ARBsARBsAgents that antagonize angiotensin receptors. Many drugs in this class specifically target the angiotensin type 1 receptor.Heart Failure and Angina Medication, weight control
HypertensionHypertensionHypertension, 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 mmMMMultiple 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/ARBsARBsAgents 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., SLESLESystemic 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 syndromeSjögren SyndromeRheumatoid Arthritis)
Adjust drug doses for GFRGFRThe 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
PatientsPatientsIndividuals 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 uremiaUremiaA 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:
In-center hemodialysisHemodialysisProcedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys.Crush Syndrome
Home hemodialysisHemodialysisProcedures which temporarily or permanently remedy insufficient cleansing of body fluids by the kidneys.Crush Syndrome
In addition to an overall increase in mortalityMortalityAll 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.
PatientsPatientsIndividuals 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 GFRGFRThe 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 proteinuriaProteinuriaThe presence of proteins in the urine, an indicator of kidney diseases.Nephrotic Syndrome in Children.
Preventive measures include:
StatinsStatinsStatins 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
Low-dose aspirinAspirinThe 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, smokingSmokingWillful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand.Interstitial Lung Diseases cessation)
Mineral and boneBoneBone 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:
CalcitriolCalcitriolThe 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
AnemiaAnemiaAnemia 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:
SodiumSodiumA member of the alkali group of metals. It has the atomic symbol na, atomic number 11, and atomic weight 23.Hyponatremia and fluid restriction
HyperkalemiaHyperkalemiaHyperkalemia 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 potassiumPotassiumAn 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
Diabetic nephropathyDiabetic nephropathyKidney 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 dialysisDialysisRenal 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 HemodialysispatientsPatientsIndividuals 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 hypertensionHypertensionHypertension, 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 albuminuriaAlbuminuriaThe presence of albumin in the urine, an indicator of kidney diseases.Kidney Function Tests and progressive loss of GFRGFRThe 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 biopsyBiopsyRemoval and pathologic examination of specimens from the living body.Ewing Sarcoma characteristically shows Kimmelstiel-Wilson nodules. Treatment involves glycemic control and ACEisACEIsA 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 nephrosclerosisNephrosclerosisHardening 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 hypertensionHypertensionHypertension, 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 nephrosclerosisNephrosclerosisHardening 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 failureRenal failureConditions 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 dialysisDialysisRenal 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 HemodialysispatientsPatientsIndividuals 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 nephrosclerosisNephrosclerosisHardening 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 patientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship with minimal proteinuriaProteinuriaThe presence of proteins in the urine, an indicator of kidney diseases.Nephrotic Syndrome in Children (< 1 g/day), no glomerular hematuriaHematuriaPresence of blood in the urine.Renal Cell Carcinoma on urinalysisUrinalysisExamination 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 dominantAutosomal dominantAutosomal 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 cystsCystsAny 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 kidneysKidneysThe 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 cystsCystsAny 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 GFRGFRThe 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 kidneysKidneysThe 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, hypertensionHypertensionHypertension, 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, hematuriaHematuriaPresence of blood in the urine.Renal Cell Carcinoma, and recurrent infectionsRecurrent infectionsCommon Variable Immunodeficiency (CVID) of the cystsCystsAny 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 cystsCystsAny 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 liverLiverThe 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 nephropathyReflux nephropathyVesicoureteral Reflux: also known as vesicoureteral refluxVesicoureteral RefluxVesicoureteral 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 nephropathyReflux nephropathyVesicoureteral Reflux usually presents in childhood and is characterized by the retrograde flowRetrograde flowVeins: Histology of urine into the kidneysKidneysThe 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 junctionUreterovesicular junctionUrinary Tract: Anatomy. This retrograde flowRetrograde flowVeins: Histology results in tubulointerstitial damage, chronic kidney disease, and the predisposition to recurrent urinary tractUrinary tractThe 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: AnatomyinfectionsInfectionsInvasion 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 arteryRenal arteryA branch of the abdominal aorta which supplies the kidneys, adrenal glands and ureters.Glomerular FiltrationstenosisStenosisHypoplastic Left Heart Syndrome (HLHS)): also known as ischemic nephropathy. CKD occurs only with bilateral stenosisStenosisHypoplastic Left Heart Syndrome (HLHS) of > 70%, as lesser degrees of stenosisStenosisHypoplastic Left Heart Syndrome (HLHS), or stenosisStenosisHypoplastic Left Heart Syndrome (HLHS) to only 1 of 2 functioning kidneysKidneysThe 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. PatientsPatientsIndividuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures.Clinician–Patient Relationship may present with refractory hypertensionRefractory hypertensionBlood pressure that cannot be controlled even with maximally tolerated doses of ≥ 5 drugs.Uncontrolled Hypertension and often have atherosclerosisAtherosclerosisAtherosclerosis 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 arteryCoronary ArteryTruncus Arteriosus disease and/or peripheral artery diseasePeripheral artery diseasePeripheral 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 smokingSmokingWillful 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 tractUrinary tractThe 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 BPHBPHBenign 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 strictureStricturePrimary Sclerosing Cholangitis, bilateral obstructing kidney stonesKidney stonesNephrolithiasis 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 massMassThree-dimensional lesion that occupies a space within the breastImaging of the Breast. For a rise in serum creatinine to develop, there must be bilateral obstruction, which is most commonly due to BPHBPHBenign 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 syndromeNephrotic syndromeNephrotic 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 proteinuriaProteinuriaThe 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 diseaseMinimal change diseaseMinimal 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 glomerulonephritisMembranoproliferative GlomerulonephritisMembranoproliferative 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 syndromeNephrotic syndromeNephrotic 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 periorbitalPeriorbitalOrbital and Preseptal CellulitisedemaEdemaEdema 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 proteinuriaProteinuriaThe presence of proteins in the urine, an indicator of kidney diseases.Nephrotic Syndrome in Children. Treatment varies by etiology and often includes glucocorticoidsGlucocorticoidsGlucocorticoids 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 syndromeNephritic syndromeNephritic 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 hematuriaHematuriaPresence of blood in the urine.Renal Cell Carcinoma and loss of GFRGFRThe 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 IgAIgARepresents 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 nephritisLupus nephritisGlomerulonephritis 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.
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