Analysis Of Bile Microbiological Culture And The Susceptibility Test Of Antibiotics After Endoscopic Nasobiliary Drainage

Objective To assessing the causative agent of biliary infection and susceptibility of antibiotics and learn their variation in order to provide a reference for clinician to administer antimicrobial therapy.To explore the distribution of biliary bacteria in patients with non-biliary infection.Methods Patients undergoing ENBD(Endoscopic Nasobiliary Drainage)in our hospital from January to April,2017 was divided into two groups,biliary infection group and non-biliary infection group.Then we conducted a retrospective study of bile microbiological culture and the susceptibility test of antibiotics from the bile of those patients.Results 1.A total of 287 patients were included in this study,including 138 males and 149 females,with an average age of 64.7±16.0 years(18~101 years).There were 142 patients diagnosed as biliary infection and other 145 patients were included in nonbiliary infection group.The positive rate of bile culture of biliary infection group was 70.4% and that of non-biliary infection group was 59.3%.The difference in the positive rate of bile culture between the two groups was statistically significant(70.4% vs.59.3%,P=0.049).2.The five leading bacteria in bile were Escherichia coli,Enterococcus faecium,Klebsiella pneumoniae,Enterococcus faecalis,and Enterococcus casselifavus in the both two groups.The bacterial content was different between the two groups.3.We found that 43.6% of patients with biliary infection was infected by ESBLs(Extended Spectrum Beta-Lactamase)producing bacteria.While the rate in non-biliary infection group was 35.1%.There was no statistically significant difference between the two groups(P=0.415).The proportion of CRE(Carbapenem-resistant Enterobacteriaceae)in the biliary infection group was 18.1%(29/160),and that in the non-biliary infection group was 24.2%(29/120),with no statistically significant difference(18.1% vs.24.2%,P=0.217).Escherichia coli(44.8% of total CRE in biliary infection group and 62.1% in non-biliary tract infection)and Klebsiella pneumoniae(41.4% of total CRE in biliary infection group and 24.1% in non-biliary tract infection)were the most common CRE in the two groups.4.Gram-negative bacteria were sensitive to tegacycline,amikacin,carbapenems,and piperacillin/tazobactam.Clinical antibiotics commonly used such as ciprofloxacin,levofloxacin,cefotaxime,cefazolin and ceftriaxone were not so sensitive.Although less drug-resistant,ceftazidime and cefepime are unsatisfactory.Meropenem was not as sensitive as ertapenem and imipenem.Gram-positive bacteria were more sensitive to tegacycline,linezolid and vancomycin,but less sensitive to fluoroquinolones.Fungi are sensitive to commonly used antifungal agents such as fluconazole,itraconazole,amphotericin B and nystatin.Conclusions At present,the drug resistance of biliary bacteria,especially gramnegative bacteria is more and more serious,where ESBLs producing bacteria and CRE increase the difficulty of antibiotic therapy.Clinicians should pay more attention to this severe situation,monitoring and updating local antibiograms,choosing antibiotics according to the antibiograms and actively controlling nosocomial infection.In addition,we found that bacteria and fungi also exist in the biliary tract of patients with non-biliary infection.The source of the microorganism is worth further study.