Evaluation of factors predicting recoverability of renal function after pyeloplasty in adults

To analyze the status of renal function after pyeloplasty in a large contemporary adult series and to detect which variables predict improvement of renal function.

85 adult patients were retrospectively identified who had undergone pyeloplasty between January 2002 and May 2011 with available pre- and postoperative diuretic scintigraphy. Preoperative differential renal function (DRF) and single-kidney GFR (SKGFR) were obtained by (99m)Tc-MAG-3 diuretic scintigraphy. Baseline-weighted (bw-) DRF and SKGFR were calculated between baseline conditions and time of last follow-up. Factors that explain the variance of bw-DRF and bw-SKGFR were determined.

The mean (SD) preoperative DRF significantly increased from 34% (11.6) to 37.2% (11.8) after pyeloplasty (p < 0.001). Similarly, mean (SD) SKGFR showed a significant improvement from 31.2 (12.9) to 35.9 (15) ml/min (p < 0.001). Patients with a lower baseline DRF (≤40%) showed a significant improvement as opposed to those with a higher baseline DRF (>40%) (p < 0.001 and 0.3, respectively). Baseline DRF and cortical thickness explained the variance in bw-DRF and bw-SKGFR with more contribution of baseline DRF.

Renal function showed improvement after pyeloplasty in adults and preoperative DRF and cortical thickness were the predicting variables.