The heart of the matter: an atypical presentation of Takayasu arteritis in the Pediatric Emergency Department.

Takayasu arteritis (TA) is a rare chronic large-vessel vasculitis of unknown etiology. Although commonly thought of as an adult disease, initial manifestations frequently appear during adolescence. This is a case discussion of an 11-year-old boy with a recent history of fever who presented with shortness of breath, sore throat, chest pain, hypertension, and a new murmur. He had a markedly elevated antistreptolysin O titer, had a prolonged PR interval, and was initially evaluated with acute rheumatic fever. After admission, he had persistent hypertension, proteinuria, and hemoptysis, which prompted a magnetic resonance angiography that revealed aortic enhancement and thickening, and he was evaluated with TA. To our knowledge, this is the first case report in the pediatric literature of TA presenting with heart block. This case highlights the recondite nature of the systemic vasculitides and emphasizes the importance of keeping a broad differential diagnosis when seeing patients who present with common complaints.