Cystic Diseases (Renal Cystic Pathology)

Congenital renal abnormalities arise from embryologic/genetic defects and cause a variety of isolated or syndromic renal disorders, including renal agenesis, dysgenesis, and ectopia. Congenital renal abnormalities are generally identified prenatally and represent approximately ⅓ of all prenatal anomalies. Because of the fetal kidney’s role in the production of amniotic fluid, oligohydramnios detected on prenatal ultrasounds often prompts the workup that identifies congenital renal anomalies. Unilateral renal involvement in the presence of a functioning contralateral kidney may only be an incidental finding later in life. In many cases, treatment is supportive.

Polycystic kidney disease (PKD) is an inherited genetic disorder leading to the development of numerous fluid-filled cysts in the kidneys. The 2 main types of PKD are autosomal recessive polycystic kidney disease (ARPKD), which is often diagnosed antenatally or shortly after birth, and autosomal dominant polycystic kidney disease (ADPKD), which is often diagnosed in adulthood. Autosomal recessive polycystic kidney disease is primarily characterized by cystic dilatations of the renal collecting ducts and intrahepatic bile duct dilatation with hepatic fibrosis. Diagnosis is through physical exam and ultrasonography. Management requires a multidisciplinary approach to slow the progression of renal disease by controlling hypertension, proteinuria, and symptoms. The prognosis of ARPKD depends on the age at presentation, along with the degree of hepatic and renal involvement. Patients progressing to end-stage renal disease (ESRD) will need renal replacement therapy.

Polycystic kidney disease (PKD) is an inherited genetic disorder leading to the development of numerous fluid-filled cysts in the kidneys. The 2 main types of PKD are autosomal dominant polycystic kidney disease (ADPKD), which is often diagnosed in adulthood, and autosomal recessive polycystic kidney disease (ARPKD), which is often diagnosed antenatally or shortly after birth. ADPKD patients commonly present with hypertension, hematuria, and flank pain. Extrarenal manifestations include intracerebral aneurysm, hepatic and pancreatic cysts, and cardiac valvular abnormalities. Diagnosis is by history, physical exam, and ultrasonography. Management requires a multidisciplinary approach and many patients require renal replacement therapy. The end goal is to slow the progression of renal disease by controlling hypertension, proteinuria, and symptoms. ADPKD prognosis is dependent on a variety of factors. A cerebral aneurysm is a complication associated with a particularly poor prognosis.