A child who has acute onset of unusual skin lesions and edema

AHEI is a benign variant of leukocytoclastic vasculitis that occurs in children younger than 2 years of age. Respiratory tract infection, drug intake, or immunization frequently precedes AHEI. Striking clinical features include acute appearance of the cutaneous lesions in otherwise healthy young infants and children, lack of visceral involvement, and self-limited progression. Laboratory tests, except for punch biopsy of the skin lesions, are nondiagnostic. Differential diagnoses include HSP and other potentially serious disorders such as meningococcemia, erythema multiforme, and Kawasaki disease. No effective therapy exists for AHEI, and treatment is supportive.