Urogenital Imaging

Acquired cystic disease, renal

refers to the development of multiple cysts in chronically failed kidneys during long-term renal replacement therapy. The condition is usually seen in dialysis patients, but may develop in chronic renal failure that does not require dialysis. Some degree of remission may occur after transplantation. These observations support the hypothesis that cyst formation is due to undefined uraemic toxins, which are incompletely removed by dialysis but are removed after successful transplantation. Cyst formation occurs in approximately 50% of dialysis patients after 3 years of treatment, and may occur in up to 90% with prolonged follow-up. Solid tumours, including adenomas, oncocytomas and adenocarcinomas (see oncocytoma renal and renal cell carcinoma), occur with increased frequency in dialysis patients, developing in up to 7% of cases.

Imaging by ultrasound, CT or MRI demonstrates a variable number of cysts of variable size. There may be from five to innumerable cysts, and cyst size may range from microscopic to 3 cm. The cysts are often small initially, but with time may enlarge and result in renal enlargement and multifocal distortion of the renal outline. Advanced cases may be radiologically difficult to distinguish from adult polycystic kidney disease. Calcification in the cyst walls and haemorrhage may be seen. Ultrasound is often of limited use in uraemic patients because the kidneys may be small, distorted and surrounded by echogenic fat. For this reason, CT is the primary modality for the detection and follow-up of acquired cystic kidney disease (Fig.1). MRI may also be helpful. Angiography may occasionally be helpful to evaluate a patient with suspected haemorrhage or tumour. Marked tortuousity of severely sclerotic vessels, with aneurysmal dilatation, lack of tapering and few branches are characteristic of this disorder. With major bleeding, the nephrogram will be distorted and the arteries will be displaced by blood in the perirenal space.

HH

To view high resolution images,
please register first.

Click  here to register.

Already registered? Enter your e-mail in the window below.
Re-register

Fig.1

Axial contrast-enhanced CT section in a patient on haemodialysis for chronic renal failure, demonstrating multiple small cystic lesions in both kidneys.
Acquired cystic disease, renal, Fig.1