Infective Endocarditis Due to Streptococcus agalactiae Complicated by a Complete Atrioventricular Block.

Infective endocarditis due to is an uncommon but potentially life-threatening condition. We report a case of infective endocarditis due to in a 79-year-old woman who presented with fatigue and appetite loss. The results of blood cultures and the vegetation detected by transesophageal echocardiography led us to the diagnosis. She was started on prompt and appropriate antibiotic therapy. Despite her favorable clinical course, she suddenly developed a complete atrioventricular block after one week of conservative treatment. She then underwent surgery with abscess drainage along with aortic and mitral valve replacement. Intraoperative findings revealed that the perivalvular inflammation insidiously extended to the cardiac conduction system and caused a complete heart block. Our case highlights the high virulence of , requiring more vigilance among clinicians.