Endocarditis Caused by Abiotrophia and Granulicatella Species

Abstract

Endocarditis caused by Abiotrophia and Granulicatella species, formerly known as nutritionally variant streptococci (NVS) is rare. It is associated with increased complications such as heart failure, systemic emboli, valve replacement surgery, treatment failures and mortality. The diagnosis of these infections is challenging due to specific nutritional growth requirements although modern techniques such as 16S rRNA sequence analysis and Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) are particularly useful. Penicillin resistance among these organisms is a growing problem. Penicillin and gentamicin combination or alternatively Vancomycin alone are the recommended treatment options, however there is increasing data regarding susceptibilities to other antibiotics. Varying susceptibilities to antibiotics among different species of NVS needs to be studied further.