Biliary tract infections caused by Enterococcus gallinarum and Escherichia coli: a rare case report.

Enterococcus gallinarum (E. gallinarum), an opportunistic pathogen with intrinsic resistance to vancomycin, has rarely been reported as a predominant pathogen responsible for biliary tract infections. Here, we report a case of biliary tract infections caused by E. gallinarum and Escherichia coli (E. coli) in a 57-year-old Chinese woman with symptoms of upper abdomen pain for 10 days. The patient initially received empiric treatment with cefmetazole but failed to improve. Subsequently, bile cultures identified E. gallinarum and E. coli, and cefmetazole was switched to linezolid and meropenem based on drug susceptibility testing. After 10 days of antibiotic therapy, the patient successfully recovered and was discharged from the hospital. The findings of this case remind us that E. gallinarum may be the causative factor of biliary tract infections, and timely identification of the causative organism and appropriate antibiotic treatment is important for optimal patient recovery.