Regression of acquired cystic disease of the kidney after successful renal transplantation.

The effect of renal transplantation on acquired cystic disease of the kidney in patients who have been on hemodialysis for more than 5 years was examined in 7 cases by computer-assisted tomography (CT scan). Almost all acquired cysts disappeared, and the size of the original kidneys decreased remarkably in 2 cases 8--10 months after transplantation. 3 other patients, in whom CT scans were performed only after transplantation, showed contracted scarred kidneys with few or no cysts. The involution of acquired cysts was incomplete in 1 case, in whom the cysts persisted for 3 years and 2 months, despite normal renal function. The last case, who was off hemodialysis only for 4 months, exhibited enlargement of the original kidneys and an increase in the number of cysts. These results suggest that a significant number of acquired renal cysts in dialyzed patients with end-stage kidney disease regress rapidly after successful renal transplantation, but this is not always so.