Polycystic Kidney Disease

• Polycystic kidney disease is a genetic condition where the healthy kidney tissue is replaced with many fluid-filled cysts.
• The enlarged kidneys may be palpable on examination of the abdomen.
• Polycystic kidney disease leads to renal failure.
• There is an autosomal dominant and an autosomal recessive type of polycystic kidney disease.
• The autosomal dominant type of polycystic kidney disease is more common.
• End-stage renal failure usually occurs before reaching adulthood in patients with ARPKD.
• Management of PKD may involve antihypertensives for hypertension, analgesia for acute pain, antibiotics for infections, drainage of symptomatic cysts by aspiration or surgery, dialysis for end-stage renal failure, and renal transplant for end-stage renal failure.
• Management of polycystic kidney disease (PKD) includes ultrasound and genetic testing for diagnosis, and Tolvaptan, a vasopressin receptor antagonist, can slow the development of cysts and the progression of renal failure in ADPKD.
• Autosomal recessive polycystic kidney disease (ARPKD) is caused by a mutation in the polycystic kidney and hepatic disease 1 (PKHD1) gene on chromosome 6 and is more rare and severe than ADPKD.
• Extra-renal manifestations of ADPKD include cerebral aneurysms, hepatic, splenic, pancreatic, ovarian and prostatic cysts, mitral regurgitation, colonic diverticula, and complications such as chronic loin/flank pain, hypertension, gross haematuria, recurrent urinary tract infections, renal stones, and end-stage renal failure.
• Patients with ARPKD may require haemodialysis within the first few days of life and may have dysmorphic features, such as underdeveloped ear cartilage, low-set ears and a flat nasal bridge.
• ARPKD is often picked up on antenatal scans with oligohydramnios, leading to underdevelopment of the fetal lungs (pulmonary hypoplasia) and respiratory failure shortly after birth.
• The affected genes in autosomal dominant polycystic kidney disease (ADPKD) are the PKD1 gene on chromosome 16 (85% of cases) and the PKD2 gene on chromosome 4 (15% of cases).
• Other management steps for PKD include genetic counselling, avoiding contact sports due to the risk of cyst rupture, avoiding NSAIDs and anticoagulants, MR angiography (MRA) can be used to screen for cerebral aneurysms.