Summary

Gemella morbillorum is facultative anaerobic, Gram-positive cocci and are a commensal part of human flora. The reported patient in this case, with a prosthetic bovine aortic valve, presented with fever, poor dental hygiene, new cardiac murmur and signs of congestive heart failure. Blood cultures were positive for a viridans streptococcal species; however, the organism could not be further identified at our institution. Echocardiogram demonstrated a decrease in ejection fraction and vegetation attached to the prosthetic aortic valve associated with a perivalvular abscess. The patient was treated with a 6-week regimen of penicillin G with gentamicin for the first 2 weeks along with cardiac surgery. The results from the 16S rRNA gene sequencing of the viridans streptococcal species were available, which reported the organism as G. morbillorum. This case adds to the literature on G. morbillorum prosthetic valve endocarditis and provides additional evidence to consider infectious endocarditis in the setting of G. morbillorum bacteraemia.