Trends in renal function after radical cystectomy and ileal conduit diversion: new insights regarding estimated glomerular filtration rate variations.

ABSTRACT

INTRODUCTION: Our objectives were to evaluate the long-term renal function after radical cystectomy (RC) and ileal conduit diversion (ICD) and to analyze year-by-year the estimated glomerular filtration rate (eGFR) and morphologic upper urinary tract changes. PATIENTS AND METHODS: We retrospectively identified 226 patients who had undergone RC and ICD from 1980 to 2008, with regular postoperative follow-up visits. The eGFR was calculated using the Modification of Diet in Renal Disease equation at baseline and during follow-up. A decrease in renal function was defined as > 1 mL/min/1.73 m(2) annually. RESULTS: The median follow-up period after RC was 91 months (range, 61-235 months). The median eGFR decreased from 66 mL/min/1.73 m(2) (range, 17-139 mL/min/1.73 m(2)) to 59 mL/min/1.73 m(2) (range, 33-102 mL/min/1.73 m(2)). A rapid decline in renal function occurred during the first 2 postoperative years (-9 mL/min/1.73 m(2) and -4 mL/min/1.73 m(2) in the first and second year, respectively), with a moderate to slight decrease in the subsequent years. Urinary obstruction was diagnosed in 51 patients (23%). Among the patients who underwent prompt surgical treatment, we did not find any association with the eGFR decline (P = .8). CONCLUSION: Patients with urinary ICD have a lifelong risk of chronic kidney disease. Regular monitoring of renal function and the morphologic upper urinary tract will permit early diagnosis and treatment of modifiable factors, avoiding irreversible kidney damage.