Bacterial infections are one of the important agents in the creation of gallstones in the gallbladder. In recent years the spread of antibiotic-resistant bacteria such as extended-spectrum beta-lactamases (ESBL) is increasing and of concern in hospitalized patients worldwide. The purpose of this study was to investigate the antibiotic susceptibility patterns of isolated bacteria from the bile specimens of patients with chronic and acute cholecystitis who had been operated by single-incision laparoscopic cholecystectomy (SILC) in Isfahan (Iran) using an antibiogram susceptibility test and molecular technique. The bile fluids of 91 patients were obtained from the Al-Zahra hospital and were cultured on specific media for the isolation of Gram-negative and positive bacteria and the disk diffusion test was done to determine the antibiotic susceptibility patterns of isolated bacteria. Finally, bacterial DNA was extracted from the bile samples and polymerase chain reaction (PCR) was performed to investigate extended-spectrum beta-lactamases genes. The bacteria Escherichia coli, Klebsiella pneumoniae, Proteus spp. and Staphylococcus aureus were detected in bile specimens cultured with high frequency, and the results showed that biliary infection increased with aging in patients with gallstone disease operated by SILC. The results showed a high frequency of ESBL genes including TEM, SHV, and CTX-M in isolated bacteria (especially Escherichia coli and Klebsiella spp.). Thus, evaluating the antibiotic susceptibility patterns and screening of ESBLs bacteria in patients with gallstones are essential. Prescribing suitable drugs, designing good strategies, and informing the medical community could decrease bile infection and antibiotic-resistant bacteria in clinical centers and hospitals
