Risk Factors and Patient Profile of Infective Endocarditis due to Gemella spp.

BACKGROUND: The diagnosis of infective endocarditis is difficult, especially when it involves atypical organisms. Therefore, our study identified risk factors of infective endocarditis caused by rare pathogen, Gemella spp .

METHODS: A systematic review was conducted to investigate characteristics of endocarditis patients infected with Gemella spp. using the search term " Gemella " and "endocarditis." Case reports were gathered by searching Medline/Pubmed, Google Scholar, CINAHL, Cochrane CENTRAL, and Web of Science databases. 83 articles were selected for review.

RESULTS: Five species of Gemella were identified. Typical patients were males between 31 and 45 years of age. On admission, patients had fever, tachycardia, and normal blood pressure. Common clinical manifestation other than fever included fatigue and weakness, chills and sweating, and nausea, vomiting, diarrhea, and weight changes. One in four reported a history of congenital heart disease, and a recent oral cavity infection. Laboratory tests reveal anemia, leukocytosis, and elevated erythrocyte sedimentation in all age groups, elevated C-reactive protein is observed among adult and geriatric populations only. Mitral and aortic valves were most commonly infected by Gemella spp. . The most common Gemella spp. -susceptible antibiotics were penicillin, vancomycin, cephalosporin, macrolide, and aminoglycosides. However, antibiotic resistance was observed against penicillin, aminoglycoside, and fluoroquinolone. Antibiotic course of at least six weeks resulted in superior clinical improvements than durations under six weeks. Finally, one in two patients underwent valve replacement or repair, with common complications affecting the cardiovascular, neurological, and renal systems. Finally, death occurred in 1 in 8 patients, half of which occurred post-surgical procedure, and the majority occurring equal to or greater than 1 week from admission.

CONCLUSION: Our systematic review highlights the importance of considering rare pathogens, particularly in the presence of predisposing risk factors.