Abstract
Granulicatella elegans is a rare cause of infective endocarditis, accounting for 1–2% of all cases. It is well recognized that this pathogen can present in association with negative blood cultures. There are higher rates of both relapse and mortality compared with endocarditis caused by other bacteria. Microbiological diagnosis can be especially challenging because many conventional blood culture media lack pyridoxal, which can be found in automated blood culture broths like BACTEC™ or BACT/ALERT® and thus they may require ‘helper’ bacteria to be culture the organism. This current case report describes a 66-year-old male patient with a 10-year history of post-inflammatory combined aortic valve disease (moderate aortic stenosis and mild aortic regurgitation). He presented with a 3-month history of recurrent fever and general deterioration. Despite targeted, prolonged, combined antibiotic treatment with intravenous penicillin and gentamicin, surgery was eventually required. An aortic prosthetic valve implantation was performed with good results. In case of subacute endocarditis, especially when a causative organism proves difficult to detect, G. elegans should be considered. Identification is greatly enhanced by using polymerase chain reaction methods and this test should be considered in all cases of culture negative endocarditis.