Epidemiology, Clinical and Microbiological Characteristics, and Outcomes of Enterococcus Bacteraemia: A 5-year-experience of a university hospital in Oman.

Objectives: This study aimed to describe the prevalence, clinical characteristics and outcomes of bacteraemia caused by Enterococcus species at a university hospital in Oman.

Methods: This observational retrospective study was conducted over a 5-year period from 2015 to 2019 at Sultan Qaboos University Hospital, Muscat, Oman. Adult patients (18 years and above) with bacteraemia caused by Enterococcus species were included. Data were collected retrospectively from the hospital information system using a standardised data collection form.

Results: A total of 142 cases of bacteraemia were observed, with E. faecalis being isolated in the majority of cases (n = 88, 62%) compared to E. faecium (n = 40, 28.2%); 83 (58.5%) cases were identified as nosocomial bacteraemia. The incidence of infection was higher among males (n = 96, 67.6%) than females (n = 46, 32.4%). There were 43 cases of polymicrobial bacteraemia along with Enterococcus species. Indwelling bladder catheter, ventilation and central venous catheters were identified as significant predisposing factors for bacteraemia. The 30-day mortality rate was 32% (n = 28) among E. faecalis and 45% (n = 18) among E. faecium bacteraemia patients. Infective endocarditis was observed in 8 (5.6%) patients, with E. faecalis being isolated in 6 (4.2%) of them. Echo findings showed tricuspid valve involvement as the most involved valve.

Conclusion: This study showed that E. faecalis and E. faecium were the most common Enterococcus species isolated. A high proportion of E. faecium isolates were resistant to ampicillin and vancomycin. Enterococcus bacteraemia remains a significant cause of healthcare-associated infections.