Infant with a rapidly progressing rash.

An infant presented to the emergency department with sudden onset of rapidly progressing erythematous macules and distal oedema. The rash was striking in appearance, covering most of the body, which raised concern for pressing infectious (eg, meningococcaemia) and other serious aetiologies. Nevertheless, the infant remained playful and was overall stable and posed a diagnostic and management dilemma. After an extensive workup and multispecialty consultations, the patient was eventually diagnosed with acute haemorrhagic oedema of infancy, a benign leucocytoclastic vasculitis. The patient received no treatment and resolution of the rash occurred within 7 days of onset. Recognition of this condition and its benign nature can spare patients from an extensive workup and reduce anxiety for both family members and healthcare providers.