Abstract 16259: Gemella Morbillorum Infective Endocarditis: A Systematic Review

Introduction: Gemella morbillorum is a facultative anaerobic gram positive bacterium that resides as normal flora in the oral cavity and gastrointestinal system. This organism has uncommonly presented as an etiology of infective endocarditis, with varying reports of resistance and complications. Methods: Transparent Reporting of Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed for the systematic review. A medical librarian (T.R.S) versed in evidence-based medicine systematically searched databases for studies assessing Gemella morbillorum infective endocarditis in patients. Publication year included inception until December 31, 2019. Using Rayyan software, 134 abstracts were screened for eligibility after duplicates were removed. Inclusion criteria was age greater than 18 years old, infective endocarditis with positive culture for Gemella morbillorum, and publication in English. 39 full text articles were reviewed for eligibility, and 38 were included in the final analysis. Results: A total of 40 cases of infective endocarditis caused by Gemella morbillorum were identified. The average age of the patients was 54 years old, 72.5% were male patients (29), 20% female (8), 7.5% unknown sex (3). Native valve endocarditis (NVE) was present in 28 of the cases, with prosthetic valve involvement in 5 cases. Left sided endocarditis was more common than right sided with 70% of cases (28) and 12.5% (5) respectively, with 17.5% (7) of cases not listing which valve was infected on echocardiography. The most common predisposing risk factor was thought to be poor dentition in 9 cases. The most common antibiotic regimen in penicillin susceptible NVE was concordant with most recent guidelines, a beta lactam with gentamicin or vancomycin in 57.5% of the cases (23). Complications occurred in 65% of cases (26), with most common complication being need for surgical intervention occurring in 30% of the cases (12). Conclusions: Gemella morbillorum infective endocarditis cases reported in literature had a high burden of complications with nearly two thirds of cases. Most common was the need for surgery with valve replacement. Antibiotic regimens in the most recent endocarditis guidelines were effective in treatment for a majority of the cases.