Evaluation of microbiological cultures in patients with acute cholecystitis

Acute cholecystitis (AC) requires emergency care. Besides surgical interventions, adequate empirical antibiotic therapy is indispensable. We aimed to analyze bile samples obtained during surgical interventions for AC. The primary aim was determine sampling frequency, pathogen prevalence (including ESKAPE strains), and to create the cumulative antibiogram of the most common bacteria (including MDR pathogens). A secondary aim was to explore the potential relationship between pathogen type (ESKAPE, MDR) and different patient characteristics in acute cholecystitis.

A retrospective observational study was conducted. Bile samples from patients undergoing acute cholecystectomy or percutaneous transhepatic gallbladder drainage for acute cholecystitis between 2005 and 2019 were analyzed. Cases were retrieved based on the respective ICD-10 codes. Descriptive and univariate methods were used.

During the study period there were 656 patients with AC; bile samples for microbiology were collected in 379 cases (57.8%). Overall, 412 bacteria, predominantly Gram-negative microbes (60.9%), were isolated. The most common bacteria included Escherichia spp. (25.7%), Streptococcus spp. (13.8%), Enterococcus spp. (13.6%). The proportion of MDR strains was 14.9%. Meanwhile, 109 of 412 pathogens (26.46%) were ESKAPE pathogens. A higher grade of inflammation was associated with a higher incidence of ESKAPE pathogens. E. coli exhibited high susceptibility (>90%) to third- and fourth-generation cephalosporins and carbapenems, but lower susceptibility to ciprofloxacin (80%) and sulfamethoxazole-trimethoprim (78%), with 25% of isolates being MDR. Among Gram-positive bacteria, 14.3% of Enterococcus spp. were vancomycin-resistant, while no MRSA was detected in bile samples.

Microbiological sampling, identifying the most common pathogens and determining the antibiotic resistance profile in AC is important to determine the optimal empirical antibiotic choice.