Endocarditis with ruptured sinus of Valsalva aneurysm caused by nonvaccine Streptococcus pneumoniae serotype 21.

Sinus of Valsalva aneurysm is a rare, catastrophic complication of endocarditis. We report an unusual case of ruptured sinus of Valsalva aneurysm associated with endocarditis that was caused by Streptococcus pneumoniae serotype 21. The patient, a 12-year-old girl, underwent surgical repair of the aneurysm and was given intravenous antibiotics for 6 weeks. She was doing well at the 6-week follow-up visit. This case is unusual because of the patient's young age at presentation, the absence of predisposing factors, and the isolation of a nonvaccine serotype 21, which revealed the epidemiologic changes of invasive pneumococcal disease. To our knowledge, this is the first reported case of endocarditis caused by this S. pneumoniae serotype.