Increased Urologic Complications in Children After Kidney Transplants for Obstructive and Reflux Uropathy

Abstract

In the cyclosporine era, reports on pediatric kidney transplant (KTx) patients with obstructive and reflux uropathy are limited by small numbers, short followup, and/or lack of control groups. Our single-center study evaluated long-term outcomes (patient and graft survival, urinary tract infections [UTIs], urologic complications) in a large cohort of KTx recipients (<20 years old). We matched our 117 study patients with obstructive and reflux uropathy with 117 controls whose KTx was needed for other reasons; all 234 underwent their KTx between April 25, 1984, and October 23, 2002. The mean age was 8.0 ± 6.2 years; mean follow-up, 133 ± 67 months. The urologic complication rate was higher in study patients (43%) than in controls (11%) (p < 0.0001), as was the UTI rate (45% vs. 2%; p < 0.0001). The metabolic acidosis and UTI rates were higher in study patients who did (vs. did not) undergo bladder augmentation (p < 0.0001). We found no significant difference between study patients and controls in patient or graft survival, acute or chronic rejection, or mean estimated glomerular filtration rates. Unique to our study is the finding of higher metabolic acidosis and UTI rates in study patients who underwent bladder augmentation.

Long-Term Outcomes of Renal Transplant in Recipients With Lower Urinary Tract Dysfunction

“…However, other recent literature has shown no significant difference in renal transplant outcomes. 1,3,[9][10][11][12][13][14][15] These studies have several limitations. Many had low numbers of patients included in the analyses (6-21 patients) 3,[12][13][14][16][17][18][19] and did not include a control group but merely compared their results to average graft and patient survival statistics.…”

“…Many studies had relatively short periods of follow-up of between 2 and 6 years 8,11,12,17,20,21 and spanned over different decades; thus, patients would have been taking different immunosuppressant drugs. 15,19,21 Furthermore, some studies had large numbers of living-donor kidney transplants 1,14,20 in the study group versus the control group, and there were no adjustments for this confounding factor. Due to these numerous limitations, the literature on this topic is unclear.…”

“…One study 18 compared bladder augmentation first versus transplant first, finding no difference in incidence of urinary tract infection after transplant or subsequent graft function. There is a higher incidence of posttransplant urinary tract infections in patients with prior LUTD 9,[11][12][13]15,16 ; however, studies have suggested that urinary tract infections do not affect long-term graft function. 10,21 The most common cause of graft loss in those with LUTD is so-called "chronic rejection."…”

“…10,21 The most common cause of graft loss in those with LUTD is so-called "chronic rejection." 15 We hypothesized that kidney transplant in patients with LUTD is a safe procedure and would have graft and patient outcomes comparable to those shown in renal transplant recipients without LUTD. Pathology in individuals with autosomal dominant polycystic kidney disease (ADPKD) is most commonly confined to the renal system.…”

Renal transplantation in infants

“…In our unit, infants usually undergo ureterocystoplasty before transplantation, whereas intestinal cystoplasty and Mitrofanoff conduit are performed after RTx, if needed. According to recent reports, CAKUT patients manage quite well after RTx and augmentation does not seem to affect the overall graft or patient survivals [11][12][13][14].…”