Infective Endocarditis Caused by Multi-drug Resistant Corynebacterium Species: A Case Report

Corynebacteria species are anaerobic, facultative, non-sporing, gram-positive bacilli that can cause infective endocarditis. In recent years, non-diphtherial Corynebacterium (diphtheroids) has increasingly been recognised as a cause of both localised and systemic infections. Determining the exact species of Corynebacteria is challenging due to their similar characteristics. Infective Endocarditis (IE) caused by Corynebacteria species is uncommon because positive blood cultures might be considered contaminants, leading to missed diagnoses. However, they can indeed cause IE, which is a severe condition. Antibiotic resistance among Corynebacteria species is common and has been increasing, making treatment challenging. In-vitro resistance to vancomycin cannot be detected reliably. Literature on IE caused by Corynebacteria species is limited, and more comprehensive information is needed. In cases of IE caused by Corynebacteria species, prosthetic valves are mainly affected, especially in elderly patients, and surgery is often required. Within the Corynebacterium genus, Corynebacterium striatum is a major causative agent of IE. Although Corynebacteria species in blood cultures are often considered contaminants from skin flora, they can also cause invasive infections such as sepsis and IE. The present case report describes the isolation of Corynebacteria species from the blood specimen of a 50-year-old male who presented with fever, headache, decreased appetite, and fatigue.