Impact Factors and an Efficient Nomogram for Predicting the Occurrence of Sepsis after Percutaneous Nephrolithotomy

Abstract

Introduction. To describe the clinical parameters of urinary stones and investigate the preoperative predictors of sepsis in patients following percutaneous nephrolithotomy (PCNL). Patients and Methods. A retrospective study of patients who underwent PCNL between August 2017 and December 2019 was performed. The patients were divided into the sepsis and nonsepsis groups according to whether they had sepsis, and their data were compared for further analysis. Results. Fifteen (6.1%) patients matching in age, gender, body mass index (BMI), and the number of access variables were included in the sepsis group. The multivariate analysis demonstrated that the staghorn calculi (OR: 12.206, $P<0.001$ ) and positive midstream urine culture (OR: 16.505, $P<0.001$ ) were independent risk factors of sepsis, while preoperative renal fistula (OR: 0.122, $P<0.001$ ) was a protective factor of sepsis. The three factors were ultimately selected to develop a nomogram to predict the probability of sepsis. The new nomogram was well calibrated and had higher diagnostic accuracy (the area under the curve: 0.916). Conclusions. Our study reveals that patients with complex stones and positive bacteriuria are associated with a significantly high risk of sepsis after surgery. The removal of obstruction before operation under certain conditions might be a reliable protective factor of sepsis.