The Analysis Of Risk Factors For Postoperative Infections Following Percutaneous Nephrolithotomy In Patients With Kidney Stones

Background:Kidney stone is one of the most common diseases of urinary system.Kidney stones could lead to recurrent urinary tract infections,urinary tract obstruction and renal failure.PCNL was the first-line treatment for larger than 2 cm stones.A high risk of infectious complications following PCNL was usually present in complex kidney stone patients.Most of the complex stones such as renal staghorn stones might always contain infectious stone composition and various organisms which could easily result in postoperative infections.Postoperative infectious complications such as fever,SIRS and sepsis may occur even if preoperative urine cultures are negative and prophylactic antibiotics are received.Postoperative infections may deteriorate into septic shock and the life-threatening stage,unless the infections were appropriately controlled in time.The research on way of predicting postoperative infections after PCNL is insufficient yet.Therefore,it is of fundamental importance and an active demand to timely predict postoperative infections for directing the perioperative antibiotic regimen.Objectives:To analyze the risk factors for systemic inflammatory response syndrome(SIRS)after percutaneous nephrolithotomy(PCNL)in kidney stone patients,and provide evidence for early prevention and treatment of postoperative infections.Materials and Methods:A total of 802 complex kidney stone patients undergone PCNL from September 2016 to September 2017 were recruited.The perioperative data about gender,age,stone burden,stone composition,operating time,access number,hydronephrosis,serum creatinine,diabetes mellitus,hypertension,previous urinary surgery,urine tests,urine cultures and stone cultures were prospectively recorded.The predictors for postoperative infections following percutaneous nephrolithotomy were compared.Results:There were 332(41.4%)females and 470(58.6%)males.The mean age was 51.98±12.22 years.The mean stone burden was 1568.65±1525.93 mm,among which 33.7%of patients had stone burden≥1600 mm~2.Positive urine cultures(UC+)accounted for 171(21.3%)patients and positive stone cultures(SC+)accounted for 242(30.2%)patients.Sixty-two(7.7%)patients developed postoperative SIRS.Significant differences between groups with and without SIRS were observed in female patients(69.4%vs 39.1%),infectious stone composition(40.3%vs 20.5%),operating time≥100min(58.1%vs 44.3%),multiple accesses(22.6%vs 9.5%),urine tests with both positive urine WBC and positive urine nitrite(WBC+NIT+;53.2%vs 11.1%),WBC-NIT-(16.1%vs 63.0%),positive urine cultures(UC+;66.1%vs 17.6%)and positive stone cultures(SC+;87.1%vs 25.4%)(All p<0.05).A multivariate logistic regression analysis revealed that operating time≥100 min(OR=2.29;95%CI=1.26-4.16),WBC+NIT+(OR=2.14;95%CI=1.09-4.21),UC+(OR=2.14;95%CI=1.07-4.29)and SC+(OR=8.89;95%CI=3.73-21.19)were independent risk factors of SIRS.The incidence of postoperative fever was higher in the group of patients with WBC+NIT+(33.0%)or the patients with both positive UC and positive SC(UC+SC+;36.4%)than that in any other groups of patients(p<0.01).The incidence of postoperative SIRS was higher in the group of patients with WBC+NIT+(28.7%)or the patients with UC+SC+(28.8%)than that in any other groups of patients(p<0.01).The incidence of postoperative sepsis was higher in the group of patients with WBC+NIT+(10%)or the patients with UC+SC+(8.3%)than that in patients with WBC-NIT-or UC-SC-(p<0.01).Preoperative WBC+NIT+could predict UC+SC+with accuracy of more than 90%.The main pathogens in kidney stones were Escherichia coli(43.8%),Proteus mirabilis(14.0%),Staphylococcus(7.4%),while main pathogens in urine were Escherichia coli(53.8%),Enterococcus(9.4%)and Proteus mirabilis(7.6%).A total of 169 patients(21.1%)were detected to have different bacteria in their urine and stones,including 149 cases of UC+SC-or UC-SC+patients and 20 cases of UC+SC+patients.The occurrence of Escherichia coli in urine(53.8%)was significantly higher than that in stones(43.8%;p<0.05),whereas the occurrence of Proteus mirabilis and Staphylococcus in stones was higher than that in urine(14.0%vs7.6%;7.4%vs 2.3%,respectively,p<0.05).The occurrence of urine Escherichia coli in group with SIRS(68.3%)was higher than that in group without SIRS(49.2%;p<0.05).Similarly,the occurrence of stone Escherichia coli in group with SIRS(55.6%)was also higher than that in group without SIRS(40.4%;p<0.05).Conclusions:WBC+NIT+in preoperative urine tests could be considered as the early and rapid predictor for UC+SC+and postoperative SIRS.The microbial spectrum in stones was different from that in urine.SIRS following PCNL was more related to Escherichia coli infections in kidney stone patients.