Abiotrophia Endocarditis in Children with No Underlying Heart Disease: A Rare but a Virulent Organism

Infective endocarditis is extremely rare in children with structurally normal hearts. The most common etiological agents are staphylococcal and streptococcal species. Nutritionally variant streptococci also classified as Abiotrophia species are a group of fastidious organisms that account for only 5% to 6% of all cases of culture-negative infective endocarditis. Only seven cases of Abiotrophia infective endocarditis have been previously reported in children with no underlying structural heart disease. We report two cases of Abiotrophia infective endocarditis in children without any predisposing factors. Both patients presented with nonspecific symptoms leading to delay in diagnosis. While bacteriological clearance was achieved in both cases, both had a complicated course including development of brain mycotic aneurysms, splenic infarction, renal failure, and irreversible damage to the mitral valve. Both patients required surgical removal of the native mitral valve and replacement. We also present review of seven cases with similar diagnosis published previously in literature and highlight important differences. Our cases highlight special challenges in management of Abiotrophia endocarditis in pediatric patients. As the organism may not be isolated in routine culture media, may present with atypical clinical symptoms and may have a complicated course even without antibiotic failure, a high index of suspicion should be maintained in children with subacute symptoms even with no underlying structural cardiac disease.