Analysis Of Etiology And Inflammatory Markers In Patients With Biliary Tract Infection After Choledocchojejunostomy

OBJECTIVE:To analyze the distribution and drug resistance of pathogenic bacteria causing postoperative biliary tract infections in patients undergoing hepaticojejunostomy in our hospital,and to explore the diagnostic value of various combinations of inflammatory biomarkers in postoperative biliary tract infections,in order to provide a theoretical basis for the rational use of antibiotics in clinical practice.METHODS:We selected the medical records of 351 patients who underwent hepaticojejunostomy at Henan Provincial People’s Hospital from September 2020 to August 2022 as the study subjects.Inclusion criteria were:(1)age between 18 and 80 years old;(2)patients who underwent biliary tract anastomosis during hospitalization;(3)complete clinical data;(4)all patients agreed to participate in the study and signed an informed consent form.Exclusion criteria were:(1)patients who were already infected before enrollment;(2)patients who had used antibiotics before surgery;(3)patients with concomitant hematological diseases.Specimens from patients who developed postoperative biliary tract infections were selected for microbiological culture and drug susceptibility testing,and the isolated pathogens were analyzed using statistical software.Based on the selection of commonly encountered pathogens in clinical practice,the drug resistance of these pathogens to commonly used antibiotics was analyzed.We collected basic information of all enrolled patients,including age,gender,underlying diseases,as well as serum levels of inflammatory biomarkers such as white blood cell count(WBC),neutrophil count(NEU),systemic immune-inflammation index(SII),C-reactive protein(CRP),and eosinophil ratio(CAR)on the day before surgery,the day after surgery,and 3 days after surgery.According to the diagnostic criteria for biliary tract infections,patients were divided into infection and non-infection groups,and the baseline data and results of various inflammatory biomarkers before and after surgery were compared between the two groups.Binary logistic regression analysis was used to establish a combined predictive index,and the diagnostic value of various indicators and their combinations in postoperative biliary tract infections was analyzed using receiver operating characteristic(ROC)curve analysis.RESULTS:(1)Basic information: 351 patients were enrolled,including 182 males and 169 females,with an average age of(61.07±11.80)years.Based on the diagnosis criteria for biliary tract infection,39 patients were diagnosed with infections and 312 patients were diagnosed without infections,resulting in an infection rate of 11.1%.Primary diseases included pancreatic cancer,carcinoma of the pancreatic head and periampullary carcinoma in 254 cases(72.4%),hilar cholangiocarcinoma in 35 cases(10%),choledocholithiasis with biliary stricture in 33 cases(9.4%),gallbladder cancer in 7 cases(2%),and other diseases in 22 cases(6.3%).(2)Distribution characteristics of pathogenic bacteria: After specimen examination,a total of 36 strains of pathogenic bacteria were isolated and cultured,including 4 cases of mixed infections,1 case of infection with 3 types of pathogenic bacteria,and 3 cases of infection with 2 types of pathogenic bacteria.Gramnegative bacteria accounted for 69.4%(25 strains),fungi accounted for 8.33%(3 strains),and Gram-positive bacteria accounted for 22.22%(8 strains).Among the Gram-negative bacteria,Escherichia coli accounted for 47.2%,Klebsiella pneumoniae accounted for 8.33%,Enterobacter cloacae accounted for 5.56%,Citrobacter freundii accounted for 5.56%,and Acinetobacter baumannii accounted for 2.78%.Among the Gram-positive bacteria,Enterococcus faecalis accounted for 13.89%,Enterococcus faecium accounted for2.78%,Streptococcus gallolyticus accounted for 2.78%,and Streptococcus bovis accounted for 2.78%.Three strains of fungi were isolated(8.33%),mainly composed of Candida albicans(8.33%).(3)Common antimicrobial drug resistance of major Gram-negative bacteria: Among the pathogenic bacteria of the Enterobacteriaceae family that were isolated and cultured,14 strains(56.0%)were ESBLproducing strains.Gram-negative bacteria were generally resistant to common antibiotics.Among them,the resistance rate of E.coli to penicillin antibiotics such as ampicillin and piperacillin,as well as first-generation cephalosporin antibiotics such as cephalothin,was over 90%,while the resistance rates to carbapenems,tigecycline,polymyxin,and amikacin were low.Klebsiella pneumoniae had low resistance rates to carbapenems such as imipenem and meropenem(both less than 40%),and no resistance was observed to novel antibiotics such as tigecycline,ceftazidime-avibactam,and polymyxin.However,the resistance rate to penicillin antibiotics such as ampicillin,compound sulfamethoxazole,and tetracycline was as high as 100%.Enterobacter cloacae had high resistance rates to cephalosporin antibiotics such as cefotaxime and ceftriaxone,as well as penicillin antibiotics such as ampicillin,and low resistance rates to carbapenem antibiotics,tigecycline,polymyxin,and amikacin.Common nosocomial infection bacteria such as Pseudomonas aeruginosa and Acinetobacter baumannii were not isolated in this study.(4)Antibiotic resistance of common antibiotics in major Gram-positive bacteria:Gram-positive bacteria isolated and identified,such as Enterococcus,showed higher resistance rates to penicillin,clindamycin,tetracycline,and ampicillin-sulbactam.However,Enterococcus and fecal Enterococcus showed 100% high sensitivity to linezolid,tigecycline,and vancomycin.(5)Comparative analysis of inflammatory biomarkers:There was no significant difference in WBC,NEU,SII,CRP,and CAR levels between the two groups of patients before surgery(P>0.05).However,on the second and third days after surgery,the levels of WBC,NEU,CAR,and CRP in both groups of patients were significantly higher than those before surgery(all P<0.05),and the levels in the infection group were significantly higher than those in the non-infection group(all P<0.05).However,there was no significant difference in SII levels between the two groups of patients on the second and third days after surgery(P>0.05).(6)Multivariate regression analysis of postoperative biliary infection:According to the regression analysis results,with postoperative biliary infection as the dependent variable,WBC on the day after surgery(OR=0.494,95% CI: 0.283-0.865,P=0.014),CRP(OR=0.953,95% CI: 0.913-0.995,P=0.027),and CAR(OR=1.990,95% CI: 0.586-6.763,P=0.017)were significant factors affecting postoperative infection.(7)Predictive value of various inflammatory biomarkers for the diagnosis of postoperative biliary infection:Through statistical analysis,it was found that CAR and CRP had high diagnostic value for postoperative biliary infection,with areas under the curve(AUC)of 0.840(95% CI: 0.757-0.923)and 0.839(95% CI: 0.754-0.923),respectively,higher than the AUC of WBC(0.774)and NEU(0.717).When the serum CAR level was 1.675 mg/g,the sensitivity was 0.733 and the specificity was 0.879.When the serum CRP concentration was 48.035 mg/L,the sensitivity was 0.733 and the specificity was 0.869.Therefore,CAR has higher specificity and is a more effective indicator for the diagnosis of postoperative biliary infection.(8)Predictive value of different combinations of inflammatory biomarkers for the diagnosis of postoperative biliary infection:Based on the combination of inflammatory biomarkers,the predictive probability was calculated.Among them,the combination of WBC and CRP showed the highest AUC value of 0.883(95% CI: 0.827-0.938),followed by the combination of any three biomarkers,WBC,NEU,and CRP,with an AUC of 0.881(95% CI: 0.821-0.941).The combination of four biomarkers had an AUC of 0.887(95% CI: 0.827-0.947),indicating that the combined application of all four biomarkers has a higher predictive value for the diagnosis of postoperative biliary infection than other combinations.CONCLUSIONS:1、Among patients who underwent biliary-enteric anastomosis surgery in our hospital,the main pathogenic bacteria causing postoperative biliary tract infection were gram-negative bacteria,such as Escherichia coli and Klebsiella pneumoniae.These strains usually show strong resistance to commonly used antibiotics.These results can guide the empirical treatment selection for postoperative biliary tract infections.2、Monitoring the serum white blood cell count(WBC),neutrophil count(NEU),C-reactive protein(CRP),and CAR levels of postoperative patients can predict the occurrence of biliary tract infection in advance.3、The combination of the four indicators has high values of AUC,Youden’s index,sensitivity,and specificity.Therefore,the combined use of these indicators can improve the diagnostic value of postoperative biliary tract infections.