Group B streptococcal infective endocarditis.

Streptococcus agalactiae (S. agalactiae), also referred as group B streptococcus (GBS), is an important pathogen in neonates and a rare cause of invasive infection in adults. It is well known that GBS endocarditis is a virulent infection that can cause serious complications. The overall mortality rate remains high despite surgical treatment. We describe a case of native mitral valve endocarditis caused by GBS in an 86-year-old woman treated medically.