Cystic Transformation in Native Kidneys in Renal Allograft Recipients with Long-Standing Good Function

Abstract

Acquired renal cystic disease develops in the native kidneys of patients with renal allografts with longstanding poor function. However, there has been no long-term prospective study of the regression or development of cysts in native kidneys of renal allograft recipients with good long-term function (serum creatinine: 114 ± 24 µmol/l). We followed 61 renal allograft recipients for 63.5 ± 29.0 months (mean ± SD) using computed tomography (CT scan) every 1 or 2 years after transplantation. The cyst grade at pretransplantation was significantly reduced at the first study after transplantation (0.98 ± 1.39 vs. 0.57 ± 0.96; p < 0.01). Baseline study after transplantation revealed that the incidence of cysts in native kidneys was 22/61 (36.1 %) and 26/61 (42.6%) in the follow-up study. In 32 patients (52.5%), there were no visible cysts in the native kidneys. In 9 patients (14.8%), there was no change in the number of cysts during follow-up, while in another 9 patients the number of cysts decreased. On the other hand, the number of cysts increased in 11 patients (18.0%) during follow-up. The mean follow-up duration was longer in the group with an increased number of cysts than in the groups with no visible cysts or a decrease in number. Biochemical analysis of cyst fluid from newly developed cysts in 2 patients showed differences from the pattern in acquired renal cystic disease of hemodialysis patients. These results indicate that after regression of acquired cysts in most allograft recipients, no or only a few cysts persist in patients with good graft function. The remaining cysts continue to regress further in some patients. On the other hand, the development of new cysts occurs in the native kidneys of some patients (18 %). These newly developed cysts may be different in nature from those of acquired renal cystic disease in hemodialysis patients.

Spontaneous retroperitoneal hemorrhage due to acquired cystic kidney disease

“…It was first described by Dunnill, Millard, and Oliver in 1977 in a study of 30 long-term hemodialysis patients where 13 of those patients demonstrated bilateral cystic disease on autopsy. 4 Transplant may decrease the severity and frequency of ACKD but does not eliminate it. By 3 years on dialysis, more than 50% of patients exhibit radiologic evidence of ACKD.…”

Renal Cystic Disease

“…However the disappearance of ACKD after transplantation is not universal (213)(214)(215)(216)(217). There are reports of children with functioning allografts who develop ACKD, as well as case reports of renal cell carcinomas occurring in native kidneys of renal allograft recipients (218).…”

Uremic Acquired Renal Cystic Disease

“…These prevalence rates are derived from a number of studies with varying numbers of patients and durations of dialysis and recovery from transplantation; at first glance, there is apparently no significant difference among the three therapeutic modalities. However, when dialysis and transplantation patients are compared, the severity of cystic changes is seen to differ greatly [17-19, 29], with one sequential longitudinal study [19] finding much less alteration in kidneys of transplant recipients. Hemodialysis and CAPD patients exhibit a similar pre valence of acquired cystic disease [9], Prevalence of cyst formation does not depend on age [28]; a figure of 33% has been obtained in children on hemodialysis and CAPD [35].…”

“…However, the process is incomplete. Several cysts may remain in the small, contracted kidney after trans plantation, and it is not known whether there is any pathogenic difference between regressed cysts and those remaining [19].…”