Henoch-Schönlein purpura: a review.

Henoch-Schönlein purpura is an IgA-mediated, autoimmune, hypersensitivity vasculitis of childhood that results in a triad of symptoms, including a purpuric rash occurring on the lower extremities, abdominal pain or renal involvement, and arthritis. However, any of the triad may be absent, which often leads to confusion in diagnosing the condition. Although the cause is unknown, Henoch-Schönlein purpura is often associated with infectious agents such as group A streptococci and Mycoplasma. It has also been associated with food reactions, exposure to cold, insect bites and drug allergies. Treatment is supportive, and children affected by this disorder need close follow-up of renal status.