Severity of Acquired Renal Cysts in Native Kidneys and Renal Allograft With Long-Standing Poor Function

To identify factors related to the development of uremic acquired cystic disease of the kidney, native and grafted kidneys were examined in four men and three women after kidney transplantation. The incidence and severity of cystic transformation of native kidneys and grafts were compared by plain computed tomographic scans. In a uremic environment (serum creatinine level of ≥265 μmol/L [3 mg/dL] for an average of 5.0 years; range, 2.8 to 8.2 years), acquired renal cysts were formed in both the native kidneys and the graft in three of the male and one of the female patients. Cysts were extensive in the native kidneys but relatively infrequent in the grafts in three of the men. One male subject was found to have acquired cysts only in the native kidney. Acquired renal cysts developed even in grafts undergoing chronic rejection, and increased numbers were found in native kidneys that were in uremic conditions for long periods, both before and after renal transplantation. These results suggest that the duration of uremia is the most important factor in the development of acquired renal cysts.