A Case of Mistaken Identity: Henoch-Schonlein Purpura Masquerading as Urticaria

Henoch-Schlonlein purpura (HSP) is a common small vessel vasculitis encountered in children. It typically presents with purpura, arthralgia, and abdominal pain following an upper respiratory tract infection. We present the case of an 8-year-old boy with a history of atopy who presented with urticaria, purpura, and arthralgias following an upper respiratory infection. Subsequent punch biopsies revealed the diagnosis of HSP. While it is uncommon for HSP to present with urticaria, the pathogenesis behind the development of urticaria and IgA-associated vasculitis are similar. Furthermore, a history of atopy has been found to be associated with a significant number of patients with HSP. We present this case to highlight an atypical presentation of HSP and to discuss factors that may play a role in the development of this disease.