Comparison of Effect of Minimally Invasive Percutaneous Nephrolithotomy on Split Renal Function: Single Tract vs Multiple Tracts

Objectives: To observe serum creatinine (SCr) and treated side glomerular filtration rate (TGFR) variations in patients with upper urinary tract calculi after minimally invasive percutaneous nephrolithotomy (MPCNL). Patients and Methods: A total of 178 patients underwent MPCNL in our institute and they were retrospectively evaluated between May 2014 and February 2016. SCr and TGFR variations were observed with renal scintigraphy using 99mTc-diethylene triamine pentaacetic acid (Tc-99m-DTPA) preoperatively and after at least 6 months of follow-up (FU). The patients were categorized into two groups according to the number of percutaneous access tracts: group I (single tract, n = 122) and group II (multiple tracts, n = 56). Results: At a mean FU of 7.6 months, SCr dropped from 192.9 +/- 151.9/L to 167.6 +/- 113.9 mu M (13.15% decrease, p = 0.008) and TGFR increased from 29.8 +/- 21.2 mL/minute preoperatively to 32.7 +/- 22.5 mL/minute postoperatively (9.79% increase, p = 0.022) in group I. Similarly, SCr dropped from 238.5 +/- 130.1 to 215.8 +/- 128.1 mu (9.50% decrease, p = 0.013) and TGFR increased from 29.6 +/- 21.4 mL/minute preoperatively to 32.9 +/- 25.1 mL/minute postoperatively (11.17% increase, p = 0.014) in group II. No statistically significant difference between two groups according to SCr or TGFR variation was observed (p > 0.05). Conclusions: Stone clearance resulted in improvement of split kidney function after single tract or multiple tract MPCNL. Single tract or multiple tract MPCNL did not show statistically significant difference in split renal function postoperative recovery.