Acquired cystic kidney disease in children undergoing continuous ambulatory peritoneal dialysis. Kyushu Pediatric Nephrology Study Group.

Our cross-sectional study aims to elucidate the prevalence of acquired cystic kidney disease (ACKD), time of occurrence of ACKD, relationship between the prevalence of ACKD and duration of dialysis, progression of cysts, and ACKD-related complications in 54 children undergoing continuous ambulatory peritoneal dialysis (CAPD). ACKD was defined as four or more cysts detected in each kidney by ultrasonography, computed tomography (CT), or magnetic resonance imaging. The presence of less than four cysts was diagnosed as solitary cysts (SCs). Noncystic primary disease was present as glomerulonephritis in 23 patients (42.6%); hypoplastic kidney, 7 patients (13.0%); reflux nephropathy, 6 patients (11.1%); and other, 18 patients (33.3%). ACKD was evident in 16 patients (29.6%) during the 57.9 +/- 39.8 months after the start of CAPD. Nine patients (16. 7%) had SCs. SCs and ACKD were detected initially in patients with 1 and 3 years of CAPD, respectively. The mean duration of CAPD for patients with ACKD (96.1 +/- 36.6 months) differed from that of patients with SCs (49.8 +/- 29.9 months) and no cysts (38.3 +/- 25.8 months). The groups were classified according to time after the start of CAPD: 0 to 4 years (n = 33), 5 to 9 years (n = 16), and longer than 10 years (n = 5). The prevalence of ACKD among these three groups was 9.1%, 50%, and 80%, respectively, and this prevalence increased significantly with increasing duration of CAPD. Of 15 patients examined two to four times by ultrasonography or CT, the number and size of cysts increased in 7 patients with ACKD and 2 patients with SC. Two patients with many and large cysts experienced gross hematuria, and one of those patients had intracystic and retroperitoneal bleeding caused by cyst rupture. No solid mass lesion was found by imaging diagnostic modalities in the 54 patients. In conclusion, the prevalence of ACKD in children undergoing CAPD is just as high as that in adults. The prevalence of ACKD and number and size of cysts increased with increasing duration of CAPD.