Virginia Research Day 2021

Medical Resident Research Case Reports

23 A Rare Case of Corynebacterium Endocarditis of a Native Valve

Samantha I Smith, DO, MS Corresponding author: Samantha.smith13@hcahealthcare.com

LewisGale Hospital-Montgomery

The majority of Corynebacterium striatum infections described in literature have been related to isolated bacteremia and central line infections but this component of skin microbiota has also been shown to be the causative organism in respiratory, wound, medical hardware/devices, and urinary tract infections. Often dismissed as a “contaminant” in blood cultures, Corynebacterium striatum is a rare etiology of infective endocarditis. Corynebacterium accounts for only 3% of all endocarditis cases, most of which involve patients with structural heart disease or prosthetic valves. However, 0.2-0.4% of cases due to Corynebacterium endocarditis occur in patients with normal heart valves. We present the case of a 67-year-old man, with a medical history of chronic atrial fibrillation, chronic obstructive pulmonary disease, Type II diabetes, hypertension, and chronic

dermatitis, presented with cough, shortness of breath, and fever. He was recently admitted at an outside facility for treatment of aspiration pneumonia and was discharged home after completing a five-day course of Moxifloxacin. Patient presented again two days later with worsening cough and shortness of breath. Blood cultures drawn at admission during grew Corynebacterium striatum and patient was started on Meropenem. His transthoracic echocardiogram showed mild mitral valve regurgitation (MVR) and a density on the mitral leaflet concerning for possible vegetation. The transesophageal echocardiogram revealed severe MVR and a mobile 1.2 cm vegetation near the tip of the anterior mitral leaflet.

continuing IV antibiotics for six weeks. A PICC line was placed and the patient was discharged to an inpatient rehabilitation facility for completion of long-term course antibiotic therapy. This case challenges the idea of Corynebacterium striatum as a benign finding due to contamination of blood cultures. Although this organism is most worrisome in patients with chronic indwelling medical devices, the risk factors for developing Corynebacterium endocarditis in patients without preexisting cardiac disease or a prior history of bacterial endocarditis are also unclear. Thus, when Corynebacterium isolated in blood culture, even in patients with native valves who have a concerning clinical picture, it is imperative to complete the workup for infective endocarditis.

An infectious disease specialist confirmed the diagnosis of endocarditis and recommended

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