Abstract: Objective：To investigate the risk factors of systemic inflammatory response syndrome (SIRS) after one-phase treatment for apyrexic calculous pyonephrosis by percutaneous nephrolithotomy (PCNL). Methods: Clinical data of consecutive apyrexic calculous pyonephrosis patients who underwent one-stage PCNL from January 2008 to December 2013 were analyzed retrospectively. The data collected included white blood cells in urine analysis before surgery, midstream urine culture, preoperative renal function, using antibiotics time before surgery, operative time, the number of tracts, intraoperative irrigation peak flow, blood transfusion, and stone composition. Chi-square, t test and Logistic regression methods were used for analysis of each factor and SIRS. Results: A total of 182 patients were enrolled in this study and 38 patients developed SIRS (20.88%). There were no statistically significant differences among white blood cells in urine analysis (P=0.483), urine culture positive (P=0.136), and struvite (P=0.324) in terms of the incidence of postoperative SIRS. Multivariate Logistic regression model indicated that risk factors of SIRS for apyrexic calculous pyonephrosis after one-phase PCNL were renal insufficiency (OR=5.41, 95% CI 1.84 to 22.64, P=0.014), operative time (OR=1.01, 95% CI 1.00 to 1.02, P=0.024), operative tracts (OR=3.37, 95% CI-1.92 to 32.55, P=0.077), intraoperative irrigation peak flow ≥500 mL/min (OR=45.87，95% CI 4.39 to 231.68, P=0.007), and blood transfusion (OR=5.98, 95% CI 1.12 to 46.66, P=0.043). The protective factor was antibiotics use for more than 3 days (OR=0.34, 95% CI -3.92 to 12.55, P=0.047). Conclusion: The incidence of SIRS after one-phase PCNL treatment for apyrexic calculous pyonephrosis was similar to that of other patients. It is relatively safe and reliable to do this. Preoperative antibiotics should be used for more than 3 days before surgery. Careful manipulation is needed to avoid blood transfusion. It is better to shorten the operative time and to reduce multiple tracts operation. Particularly, irrigation peak flow ≥500 mL/min should be avoided in the circumstance of bleeding or turbid urine.

Key words: Kidney calculi, Nephrostomy, percutaneous, Systemic inflammatory response syndrome, Pyonephrosis, Risk factors