Risk Factors for Acute Cholangitis Caused by Enterococcus faecalis and Enterococcus faecium

Risk factors for cefmetazole-non-susceptible bacteremia in acute cholangitis

INTRODUCTION

Cefmetazole (CMZ), an antibiotic with limited international distribution, is recommended by the Tokyo Guidelines 2018 (TG18) for non-severe cases of acute cholangitis (AC). However, the risk factors for CMZ-non-susceptible (CMZ-NS) bacteremia in AC remain unclear. Here, we aimed to investigate the risk factors for CMZ-NS bacteremia and evaluate mortality in patients with AC.

METHODS

This single-center, retrospective, observational study included all patients diagnosed with definite bacteremic AC, based on TG18, from April 2019 to March 2023. Risk factors for CMZ-NS bacteremia were analyzed by univariate, and age- and sex-adjusted, logistic regression analyses. Mortality was compared by cause of obstruction, CMZ-susceptible/CMZ-NS bacteremia, and initial treatment.

RESULTS

In total, 165 patients were enrolled. CMZ-NS bacteremia was diagnosed in 46 (27.9 %) patients. Histories of diabetes mellitus, hepato-biliary-pancreatic cancer, malignant biliary obstruction, and endoscopic sphincterotomy were identified as significant factors associated with the risk of CMZ-NS bacteremia. Thirteen patients died within 30 days of hospital admission. The mortality of patients with AC and malignant biliary obstruction was statistically higher than that of patients with bile duct stones. No patients with AC and bile duct stones died in the group with CMZ-NS bacteremia and inappropriate initial antibiotics.

CONCLUSIONS

In AC, a history of diabetes mellitus, hepato-biliary-pancreatic cancer, malignant biliary obstruction, and endoscopic sphincterotomy are associated with an increased risk of CMZ-NS bacteremia. Therefore, the choice of empiric therapy for AC should be based on the etiology and patient background, rather than on the severity.

The dysregulation of biliary tract microflora is closely related to primary choledocholithiasis: a multicenter study

Bile microecology changes play an important role in the occurrence and development of choledocholithiasis. At present, there is no clear report on the difference of bile microecology between asymptomatic patients with gallbladder polyps and choledocholithiasis. This study compared bile microecology between gallbladder polyp patients and patients with choledocholithiasis to identify risk factors for primary choledocholithiasis. This study was conducted in 3 hospitals in different regions of China. Bile samples from 26 patients with gallbladder polyps and 31 patients with choledocholithiasis were collected by laparoscopic cholecystectomy and endoscopic retrograde choledocholithiasis cholangiography (ERCP), respectively. The collected samples were used for 16S ribosomal RNA sequencing and liquid chromatography mass spectrometry analysis. The α-diversity of bile microecological colonies was similar between gallbladder polyp and choledocholithiasis, but the β-diversity was different. Firmicutes, Proteobacteri, Bacteroidota and Actinobacteriota are the most common phyla in the gallbladder polyp group and choledocholithiasis group. However, compared with the gallbladder polyp patients, the abundance of Actinobacteriota has significantly lower in the choledocholithiasis group. At the genera level, the abundance of a variety of bacteria varies between the two groups, and Enterococcus was significantly elevated in choledocholithiasis group. In addition, bile biofilm formation-Pseudomonas aeruginosa was more metabolically active in the choledocholithiasis group, which was closely related to stone formation. The analysis of metabolites showed that a variety of metabolites decreased in the choledocholithiasis group, and the concentration of beta-muricholic acid decreased most significantly. For the first time, our study compared the bile of gallbladder polyp patients with patients with choledocholithiasis, and suggested that the change in the abundance of Actinobacteriota and Enterococcus were closely related to choledocholithiasis. The role of Pseudomonas aeruginosa biofilm in the formation of choledocholithiasis was discovered for the first time, and some prevention schemes for choledocholithiasis were discussed, which has important biological and medical significance.

Variability of bile bacterial profiles and drug resistance in patients with choledocholithiasis combined with biliary tract infection: a retrospective study

Background

Biliary tract infection is a common complication of choledocholithiasis. This study aimed to analyse the distribution of pathogenic bacteria in bile cultures from patients with choledocholithiasis combined with biliary tract infection to guide clinical application of antimicrobials and reduce the emergence of drug resistance.

Methods

A total of 880 patients were enrolled in this retrospective study from 30 March 2017 to 31 August 2022 at the Affiliated Hospital of Qingdao University in China. Bile specimens were extracted for microbiological culture under aseptic conditions using endoscopic retrograde cholangiopancreatography. Bacterial culture, strain identification, and antimicrobial susceptibility testing were conducted according to the standard protocol. Baseline data were retrieved from patient files.

Results

Overall, 90.34% (795/880) of bile samples showed positive microbiological results and 37.50% (330/880) demonstrated polymicrobial infections. Among the 795 bile specimens with positive culture results, 1,216 pathogenic bacteria were detected, with gram-negative bacilli accounting for 56.33%, gram-positive cocci for 41.86%, and fungi for 1.81%. The predominant gram-negative bacilli in the bile cultures were Escherichia coli (30.43%) and Klebsiella pneumoniae (13.98%), whereas the main gram-positive cocci were Enterococcus faecium (14.04%) and E. casseliflavus (4.28%). The annual trend analysis revealed a gradual decrease in the proportion of gram-negative bacilli and a gradual increase in the proportion of gram-positive cocci, with a concomitant decrease in the dominance of E. coli. Both E. faecium and E. coli showed high resistance to conventional antibiotics but high sensitivity to piperacillin/tazobactam, carbapenems, amikacin, and vancomycin.

Conclusions

A significant change has occurred in the bile bacterial spectrum in patients with choledocholithiasis and biliary tract infection. The incidence of gram-positive cocci infections has increased annually, while that of gram-negative bacilli and E. coli infections has decreased. Antibiotic administration should be tailored based on the local bacterial profile.

Association of short-course antimicrobial therapy and bacterial resistance in acute cholangitis: Retrospective cohort study

Background and study aims Although the number of resistant bacteria tends to increase with prolonged antimicrobial therapy, no studies have examined the relationship between the duration of antimicrobial therapy and increase in the number of resistant bacteria in acute cholangitis. We hypothesized that the short-term administration of antimicrobial agents in acute cholangitis would suppress bacterial resistance. Patients and methods This was a single-center, retrospective, observational study of patients with acute cholangitis admitted between January 2018 and June 2020 who met the following criteria: successful biliary drainage, positive blood or bile cultures, bacteria identified from cultures sensitive to antimicrobials, and subsequent cholangitis recurrence by January 2022. The patients were divided into two groups: those whose causative organisms at the time of recurrence became resistant to the antimicrobial agents used at the time of initial admission (resistant group) and those who remained susceptible (susceptible group). Multivariate analysis was used to examine risk factors associated with the development of resistant pathogens. Multivariate analysis investigated antibiotics used with the length of 3 days or shorter after endoscopic retrograde cholangiopancreatography (ERCP) and previously reported risk factors for the development of bacterial resistance. Results In total, 89 eligible patients were included in this study. There were no significant differences in patient background or ERCP findings between the groups. The use of antibiotics, completed within 3 days after ERCP, was associated with a lower risk of developing bacterial resistance (odds ratio, 0.17; 95% confidence interval, 0.04-0.65; P =0.01). Conclusions In acute cholangitis, the administration of antimicrobials within 3 days of ERCP may suppress the development of resistant bacteria.

Korean Guidelines for Use of Antibiotics for Intra-abdominal Infections in Adults

The guidelines are intended to provide practical information for the correct use of antibiotics for intra-abdominal infections in Korea. With the aim of realizing evidence-based treatment, these guidelines for the use of antibiotics were written to help clinicians find answers to key clinical questions that arise in the course of patient care, using the latest research results based on systematic literature review. The guidelines were prepared in consideration of the data on the causative pathogens of intra-abdominal infections in Korea, the antibiotic susceptibility of the causative pathogens, and the antibiotics available in Korea.

Enterococcus raffinosus, Enterococcus durans and Enterococcus avium Isolated from a Tertiary Care Hospital in Romania-Retrospective Study and Brief Review

(1) Background: This paper aims to provide a description of non-faecalis non-faecium enterococci isolated from a tertiary care hospital in Romania and to briefly review the existing literature regarding the involvement of Enterococcus raffinosus, Enterococcus durans and Enterococcus avium in human infections and their antimicrobial resistance patterns; (2) Methods: We retrospectively analyzed all Enteroccocus species isolated from the “Prof. Dr. O. Fodor” Regional Institute of Gastroenterology and Hepatology from Cluj-Napoca during one year focusing on non-faecalis non-faecium Enterococci. A brief review of the literature was performed using case reports involving Enterococcus raffinosus, Enterococcus durans and Enterococcus avium; (3) Results: Only 58 out of 658 Enteroccocus isolates were non-faecalis non-faecium and met the inclusion criteria. These species were isolated more often (p < 0.05) from the surgical ward from mixed etiology infections with E. coli. In our review, we included 39 case reports involving E. raffinosus, E. durans and E. avium; (4) Conclusions: Isolation of non-faecalis non-faecium enterococci displays an emerging trend with crucial healthcare consequences. Based on the analysis of the case reports, E. avium seems to be involved more often in neurological infections, E. durans in endocarditis, while E. raffinosus displays a more heterogenous distribution.

[Bacterial hepatobiliary infections : Pathogen spectrum, antimicrobial resistance and current treatment concepts]

Ascending cholangitis and pyogenic liver abscesses are acute febrile bacterial hepatobiliary diseases. Nowadays they frequently occur in patients with structural changes of the biliary system and are usually treated by a combination of interventional drainage procedures and antimicrobial therapy. While Gram-negative Enterobacterales were identified as major causes in the past, biliary tract interventions and antibiotic exposure have contributed to an increase in enterococcal species and extended spectrum beta-lactamase (ESBL)-producing Enterobacterales. When selecting an appropriate empirical treatment the treating internist must consider local and individual risk factors for antimicrobial resistance in addition to pharmacokinetic aspects and disease severity to reduce the likelihood of treatment failure.

Microbiological analysis of patients with first and recurrent episodes of acute cholangitis in a middle-sized hospital: A single-center retrospective study in rural North Kyoto, Japan

BACKGROUND

Knowledge of the bacterial spectrum involved in acute cholangitis is essential for adequate empiric antibiotic treatment. There is a lack of published data comparative data between patients with first and recurrent episodes of acute cholangitis. This study aimed to analyze the microbial spectrum in patients with first and second episodes of acute cholangitis.

METHODS

We retrospectively assessed 251 patients with first episodes of acute cholangitis between January 2014 to September 2020.

RESULTS

At the first episode of acute cholangitis, the predominant strains belonged to Escherichia coli (17.9%), followed by Klebsiella spp. (15.5%), Enterobacter spp. (6.4%), and Enterococcus spp. (5.6%). During follow-up, acute cholangitis recurred in 109 patients; at the second episode, the predominant strains belonged to Enterococcus spp. (35.8%), followed by Klebsiella spp. (27.5%), Enterobacter spp. (22.9%), and Escherichia coli (15.6%). Enterococcus spp. were the most common pathogen in patients with second episode of acute cholangitis, regardless of whether the cholangitis was caused by a malignant tumor or a benign disease.

CONCLUSIONS

Unlike in patients with a first episode of acute cholangitis, clinicians should consider empirical treatment with anti-enterococcal antibiotics in patients with recurrent episodes of acute cholangitis.