Ultrasonography of the native kidney in dialysis and transplant patients.

The native kidneys in patients on dialysis or after transplantation tend to be overlooked until problems occur in relation to them. Their appearance can be variable and does not bear any consistent relationship to the cause of the renal failure; although in some cases, such as polycystic kidney disease, there are specific changes to be seen. Size can also be variable with little correlation to pathology in most cases. Acquired cystic disease of the kidneys is seen in up to 92% of long-term dialysis patients and also can be seen in patients with chronic renal failure. Proliferative changes occur in the kidneys which result in the development of cysts, adenomas and, in approximately 1% to 2% of dialysis patients, malignant lesions. It is probable that these changes are caused by a combination of factors, including circulating agents which are not cleared adequately by dialysis. There is some evidence that these changes are halted, or even reversed following a successful transplant. Problems with infection and hemorrhage may occur in patients with polycystic kidney disease. Problems with infection may also occur in patients with calculi, with longstanding pyelonephritis, or reflux.