This 51 year old man underwent CT scan of the abdomen to exclude a ureteric renal calculus. He was known to have autosomal dominant polycystic kidney disease and chronic renal failure. A coronal reformat shows multiple cysts in both kidneys with little remaining normal renal parenchyma. High density within some of the cysts may be due to haemorrhage into cysts. It is a common condition, with an incidence of 1:400-1000 live births. The condition is autosomal dominant, with 10% due to spontaneous mutations. The PKD1 and PKD2 genes have been identified. Proliferation of renal tubular cells occurs with diverticula of nephrons developing, leading to cyst development. There is an association with polycystic liver disease (40% of patients with AD polycystic kidney disease), congenital hepatic fibrosis, biliary hamartomas, Caroli disease, pancreatic and splenic cysts, intracranial aneurysms and cardiac valve defects (in 20-25%).

1. Kumar et al. Robbins and Cotran Pathologic Basis of Disease. Elsevier Saunders 2005.
2. Federle et al. Diagnostic Imaging: Abdomen. Amirsys 2004.
Credit: Dr Bernard Ng