Skin lesions, angioedema, eosinophilia, and hypocomplementemia.

A six-year-old girl with recurrent urticaria and angioedema, vasculitis, and probable renal disease exhibited marked blood eosinophilia, increased levels of serum IgE, circulating Clq precipitins, and hypocomplementemia with evidence of activation of complement by the classic pathway. Biopsies of skin and muscle revealed heavy infiltrations of the vessel walls with eosinophils. Immunofluorescence studies revealed deposition of IgM, IgE, and C3 in the vessel walls. Exacerbations of the disease were associated with an increase in the eosinophil count and a decrease in the serum levels of C4 and C3. Remission was achieved with corticosteroid therapy. This patient has many features in common with the syndrome of skin lesions, angioedema, and hypocomplementemia recently described in adults.