Vascular IgA deposits in clinically normal skin of patients with renal disease.

Direct immunofluorescent tests for IgA deposits were done on biopsies of normal appearing skin from 49 patients with proven renal disease and 7 healthy individuals, in order to evaluate the method in the diagnosis of IgA nephropathy. Many of the 28 patients with IgA nephropathy had high levels of IgA deposition, often accompanied by notable deposits of IgM, Clq and fibrin, and less frequently by C3 and IgG, in small vessels of the superficial dermis. However, some of the 21 patients with other renal diseases had heavy deposits of IgA, limiting the usefulness of the test as a diagnostic aid.