Actinobacillus endocarditis associated with hypertrophic cardiomyopathy

Infective endocarditis can be associated with complex clinical presentations, sometimes with a difficult multi-disciplinary management. Actinobacillus actinomycetemcomitans belongs to the Haemophilus species, Actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens and Kingella species group, responsible for 5% to 10% of infective endocarditis in native heart valves. These organisms have slow fastidious growth pattern, often associated with negative cultures, and cause systemic embolism with abscess formation. The authors present the case of a 59-year-old man, admitted due to fever of unknown origin, with a personal history of obstructive hypertrophic cardiomyopathy and recent dental manipulation. The diagnosis of mitral valve's endocarditis was established after a transoesophageal ecocardiography, with a late isolation of A actinomycetemcomitans in blood culture. Despite the institution of antibiotic therapy, the patient suffered from multiple episodes of septic embolism: skin, mucosae, cerebral abscesses, spondylodiscitis and uveitis. He was submitted to heart surgery with miectomy and replacement of the native mitral valve by a mechanical prosthesis, while on antibiotics.