Rashes are one of the most common presenting symptoms in the emergency department setting; they may be a primary diagnosis or a symptom of systemic disease. Accurate diagnosis of a rash may be challenging and requires clinical acumen, systematic history and physical examination, and judicious use of diagnostic testing. This case study reviews Henoch–Schönlein purpura (HSP) or IgA vasculitis, a common vasculitis of childhood. Although typically a self-limited disease, HSP may cause serious complications in a small subset of patients and requires monitoring. In addition, there are several differential diagnoses that may mimic HSP that are more serious. This article reviews the case of a 6-year-old boy who presented to a community emergency department and had a nontypical clinical course.