Analysis Of Pathogenic Bacteria And Related Factors Of Postoperative Infection Of Upper Urinary Calculi

Objective:To investigate the etiological characteristics and drug resistance of post-operative infection in patients with upper urinary tract calculi(UUTC),and to construct a Nomogram model for predicting post-operative infection based on independent risk factors.Methods:The clinical data of UUTC patients admitted to our hospital from May 2015 to May 2018 were retrospectively analyzed.Age,sex,diabetes mellitus,stone size,obstruction type,preoperative infection,surgical method and operation time were collected.Pathogens in patients with post-operative urethral infection were detected by VITEK-32 automatic bacterial analyzer,and then the susceptibility test of common pathogens was carried out by disk diffusion method.Independent risk factors for urinary tract infection after UUTC endoscopy were analyzed by multiple logistic regression model and OR was calculated.Nomogram model is drawn and validated internally according to the results of multivariate logistic regression model and RMS software package in version 3.5.2 of R.Results:Of 2500 patients treated with UUTC endoscopy,146 had urinary tract infection after operation,the incidence of infection was 5.84%.Among 194 strains of pathogenic bacteria,113 strains were gram-negative,accounting for 58.25%.Escherichia coli accounted for 28.87%,followed by Pseudomonas aeruginosa(13.92%)and Acinetobacter(2.06%).58 strains of Gram-positive bacteria accounted for29.90%.Enterococcus faecalis accounted for the highest proportion(17.52%),followed by Enterococcus faecalis(6.19%)and Staphylococcus epidermidis(2.58%).23 strains offungi accounted for 11.85%.Among 65 gram-negative bacteria,E.coli had the highest resistance to cefazolin(89.38%),followed by ampicillin(87.61%)and imipenem(2.65%).Cefazolin,ceftriaxone,ceftazidime,cefuroxime,ampicillin,norfloxacin and ciprofloxacin were more than 50%.Among 34 Gram-positive bacteria,Enterococcus faecalis had the highest resistance to gentamicin(94.12%),followed by penicillin G(73.53%)and the lowest resistance to vancomycin and teicoplanin(0.00%).Gentamycin,penicillin G and erythromycin accounted for more than 50%of drug resistance.Age(>60 years old)(HR:11.415,95%CI:2.714-12.684),female(HR:4.726,95%CI:1.167-5.824),diabetes mellitus(HR:9.328,95%CI:2.413-10.152),calculi>5cm(HR:6.413,95%CI:1.748-8.503),a cute obstruction(HR:6.349,95%CI:1.692-8.419),ureteroscopic surgery(HR:6.328,743:10.152).95%CI:1.387-7.042),operation time>2 hours(HR:10.275,95%CI:2.416-10.923)were independent risk factors for urinary tract infection after UUTC endoscopy,while percutaneous nephroscopic surgery(HR:0.869,95%CI:0.658-0.987)was the protective factor for urinary tract infection after UUTC endoscopy.The Nomogram model for predicting urinary tract infections after UUTC endoscopy was constructed with a C-index of 0.729(95%CI:0.648-0.841).Conclusion:The incidence of infection symptoms is high in UUTC patients after endoscopic treatment.Escherichia coli is the main gram-negative pathogen leading to infection.Enterococcus faecalis is the main Gram-positive pathogen.Clinical treatment should be based on drug sensitivity test results and patients' own conditions to formulate a comprehensive drug regimen to ensure safety while improving.Therapeutic effect and improvement of prognosis.The Nomogram model constructed according to this study can effectively screen high-risk patients before operation,so as to improve the operation plan and treatment plan after operation.