Idiopathic retroperitoneal fibrosis: clinical features and long-term renal function outcome.

PURPOSE: To evaluate the long-term renal function outcome of management of retroperitoneal fibrosis (RPF)-induced ureteral obstruction.

METHODS: Thirty-six patients with idiopathic RPF-induced ureteral obstruction were classified according to the management type into two groups, group A; managed by indwelling JJ stent and group B managed by ureterolysis and omental wrapping (UOR). The primary outcome was to define the long-term outcome of management on RF. It was evaluated by changes in serum creatinine and estimated GFR (eGFR) using Modification of Diet in Renal Disease equation where 20% changes in eGFR is considered significant. The second outcome is to compare the outcomes between both groups.

RESULTS: After 27.5 (1-124) months, median (range) follow-up, median (range) serum creatinine increased significantly from 1.5 (0.8-8.1) to 1.6 (1-12.1) mg/dl (p value =0.04) and eGFR showed non-statistical significant reduction from 43 (5-110) to 41 (5-88) ml/min/1.73 m2 (p value =0.3). Eight (22.2%), 12 (34.4%) and 16 (44.4%) patients showed stable, increased and decreased eGFR. Group A showed statistically significant increased serum creatinine and insignificant decreased eGFR (p value =0.04 and 0.09), while group B showed statistically insignificant changes in serum creatinine and eGFR (p value =0.5 and 0.9). In group B, nine (21.4%) renal units are still harboring JJ stents.

CONCLUSION: For idiopathic RPF, UOR avoided indwelling ureteral stents in 78.6% of renal units with apparent better long-term renal function outcome.