Group B Streptococcal Myocarditis

Abstract

Bacterial myocarditis is an uncommon form of infectious myocarditis. The definitive diagnosis requires histopathology with evidence of bacterial invasion. We report a case of group B streptococcal myocarditis secondary to septicaemia with complete atrioventricular (AV) block and new left bundle branch block. The histopathology revealed patchy small foci of myocyte necrosis. The necrotic areas contained mixed inflammatory cell infiltration with a predominance of neutrophils. Necrosis in AV node was also observed. Gram stain in the necrotic area showed clusters of gram positive cocci in agreement with the results of haemoculture. Bacterial myocarditis is a devastating complication of bacteraemia. This case highlights the ability of group B streptococci to cause life-threatening infections in adults without clear predisposing factors to serious infection. Bacterial myocarditis may progress quickly and be associated with a fatal outcome.