Abstract
The etiology of HSP is unknown, but there are many associated disorders
including preceding bacterial or viral infections. Various other associated problems
have been reported with HSP including sensitivity to azodyes and salicylates and
drug sensitivities. Henoch-Scho¨nlein purpura has also been associated with pregnancy, cryoglobulinemia, lymphoma, and adenocarcinoma. The immunologic basis
for these associations is unknown. Elevated serum IgA is seen in approximately
one-half of patients with HSP. IgA complexes may be cleared less quickly in those
patients susceptible to HSP. IgA1 is thought to be the major immune globulin
related to renal disease in HSP. Recent studies point to a possible defect in glycosylation of the ‘‘hinge’’ region of IgA1 as a cause for renal damage (20,21).