A Risk-Based Assessment of Enterococcal Bloodstream Infection : Suggesting considerations in Empirical therapy strategies in a Tertiary care Hospital

Enterococcal bloodstream infections (E-BSIs) pose a significant challenge due to their unique intrinsic and increasing resistance. Empirical treatment guidelines are often ineffective in E-BSI, as Antibiotic policies mainly address Gram-negative bacilli and MRSA for Hospital-acquired infection (HAI)in India. The study was designed to investigate the risk factors, infection source, species profile, antimicrobial susceptibility and clinical outcomes in diagnosed E-BSI patients at a tertiary care centre in India. From the blood culture samples from August 2022 to July 2023, 52 non-duplicate blood culture isolates of Enterococcus species were identified with categorisation of vancomycin resistance genes, and the patients were followed up for risk factors, probable sources, and ongoing therapies, with a switch to definitive therapy for the outcome. Of 52 confirmed E-BSI cases, the species distribution was as follows: E. faecium (61.5%), E. faecalis (26.92%), E. gallinarum (9.61%), and E. durans (1.92%). Antimicrobial resistance was significantly higher in E. faecium. Nine isolates (17.3%) were vancomycin-resistant enterococci (VRE), with diverse outcomes. HAI comprised 44.23% of cases. The overall mortality rate was 26.9% and ICU patients had significantly higher mortality, with significant risk factors being invasive medical devices (59.6%), followed by bedridden status (23%) and immunosuppression (9.61%). Significant risk factors included the presence of invasive medical devices (59.6%), followed by a bedridden status (23.0%) and immunosuppression (9.6%). Patients with early empirical therapy that has enterococcal coverage showed a protective effect on survival. However, switching over to definitive therapy alone could not significantly reduce mortality. This study underscores the importance of early empirical therapy with enterococcal coverage in high-risk patients. Timely initiation of empirical coverage appears more crucial than later definitive therapy adjustments in improving survival. Invasive device use remains a significant risk factor, reinforcing the need for stringent infection control to prevent HAI, including E-BSI.