A Case of Gemella morbillorum Causing Multi-valvular Endocarditis

TL;DR

A 31-year-old man developed multi-valvular endocarditis caused by Gemella morbillorum, originating from a dental infection and requiring surgery and prolonged antibiotic treatment.

Contribution

This case highlights Gemella morbillorum as a rare but significant cause of multi-valvular endocarditis linked to dental infection.

Findings

Gemella morbillorum was identified as the causative agent of multi-valvular endocarditis.

Dental carries were confirmed as the source of infection.

The patient required valve replacement and six weeks of IV antibiotic therapy.

Abstract

This is the case of a 31-year-old man with no significant past medical history who presented to the emergency department experiencing persistent fevers, chills, and malaise for the past 2-3 weeks. During this period, he had multiple urgent care visits for possible left-sided otitis media which was treated with short a course of Augmentin. While on antibiotics his symptoms would improve, but they would reappear once he had finished treatment. The patient also had significant dental carries with a chronic right molar infection. At the emergency department, blood cultures grew two out of two Gemella morbillorum. Transthoracic echocardiography showed a 1 cm x 0.5 cm mobile density on the left coronary cusp of the aortic valve with moderate-severe aortic insufficiency. The patient was started on empiric IV vancomycin. Further workup revealed that the source of infection was dental carries. While proceeding with a transesophageal echocardiogram, the patient went into flash pulmonary edema requiring ICU admission. Imaging revealed an elongated 1.7 cm x 0.6 cm vegetation attached to the base of the left coronary cusp on the left ventricular outflow tract side with severe aortic regurgitation and a small 0.8 cm x 0.8 cm vegetation on the atrial side of the anterior mitral leaflet at A2 associated with mitral leaflet perforation with severe mitral regurgitation. Oral surgery removed the infected teeth. Cardiothoracic surgery performed open heart valve replacement which revealed a completely destroyed aortic valve, droplet vegetation, and destruction of the mitral valve leading to mechanical valve replacement. The patient received a two-week course of gentamycin while in the ICU with meropenem. Once sensitivities were back, he was switched to IV penicillin therapy for a total of six weeks.