Pre- and postoperative predictors of infection-related complications in patients undergoing percutaneous nephrolithotomy

Introduction: We aim to describe pre- and postoperative predictors of infection-related complications in individuals undergoing percutaneous nephrolithotomy (PCNL). Patients and Methods: Patients treated with PCNL from 2009 to 2013 were reviewed. Patients with positive urine or stone cultures received extended antimicrobial treatment. All others received 7 days of empirical therapy preoperatively and postoperatively. Pre- and postoperative predictors of infectious complication were identified. Results: We identified 227 patients who underwent primary PCNL with infectious complications occurring in 37 (16%): 11 (5%) urinary tract infection/pyelonephritis, 21 (9%) systemic inflammatory response syndrome (SIRS), and 2 (0.9%) sepsis. There were no significant differences between those with and without infectious complication with regard to age, gender, stone size, presence of diabetes, or procedure duration. Those with infectious complication were more likely to have a positive intraoperative stone culture (p = 0.01), struvite stone composition (p < 0.01), staghorn calculi (p < 0.001), and multiple stones (p = 0.02). Preoperatively, on multivariable analysis, only the presence of a staghorn calculus remained independently associated with increased risks of fever/SIRS/sepsis (odds ratio [OR] 3.14; p = 0.02) and total infectious complications (OR 2.53; p = 0.02) following PCNL. After controlling for pre- and post-PCNL risk factors, again, only staghorn calculi remained significantly associated with fever/SIRS/sepsis (OR 3.41; p = 0.01) and total infectious complications (OR 2.91; p = 0.01), with presence of multiple stones approaching significance (OR 4.2, confidence interval [CI]: 0.96, 18.6; p = 0.06). Conclusions: In individuals undergoing PCNL on preoperative antibiotics, risk of SIRS/sepsis was low. The presence of a staghorn calculus confers a greater than threefold increased risk of postoperative infection with multiple stones approaching a significant risk. Patients with large stone burdens should be counseled appropriately regarding these risks.