Cardiobacterium hominis Endocarditis in a Healthy Adult - Rare but Not to Be Missed

Abstract

Cardiobacterium hominis is part of HACEK group and an atypical cause of infective endocarditis. It may cause similar clinical presentation to other cause of endocarditis. Establishing the diagnosis is challenging as it is a fastidious organism which rarely affects individual without previous cardiac lesion and requires advanced diagnostic tools for identification of species. A 23-year-old previously healthy man presented with intermittent fever for two months associated with palpitations and lethargy. He had undergone a dental procedure four months before the presenting symptoms. Physical examination revealed a pansystolic murmur best heard over the apex. Three aerobic blood culture bottles were positive and Gram stain consistently showed pleomorphic Gram-negative rods. The organism grew as tiny pin-point opaque colonies on sheep blood agar and chocolate agar after 48 hours of incubation but no growth was seen on MacConkey agar. Unsuccessful identification with VITEK 2 NH and VITEK 2 GN was later confirmed by polymerase chain reaction as C. hominis. He was treated with a six-week course of antibiotics.