title: Utility of skin biopsy in the diagnosis of IgA nephropathy.
abstract: Thirty-seven patients with the diagnosis of IgA nephropathy were evaluated with punch skin biopsies of non-sun exposed skin. Biopsies were performed regardless of clinical activity. Biopsies were positive for IgA immunofluorescence in two patients. In an effort to enhance positivity of biopsies, patients were pretreated with 0.1 mL of histamine and then repeat biopsies were performed on 14 patients with previously negative skin biopsies. All 14 patients had negative repeat skin biopsies for IgA immunofluorescence. A review of the literature revealed 76 positive skin biopsies in a total of 138 patients with IgA nephropathy. Positive skin biopsies were also reported in 169 of 510 patients with other renal diseases. We conclude that a 4 mm punch skin biopsy with or without histamine is an insensitive and non-specific test for diagnosing IgA nephropathy.
mesh_terms: D001706:Biopsy; D005922:Glomerulonephritis, IGA / Q000276:immunology* / Q000473:pathology; D006632:Histamine; D006801:Humans; D005779:Immunodiffusion; D007122:Immunoelectrophoresis; D007070:Immunoglobulin A / Q000032:analysis*; D012867:Skin / Q000276:immunology* / Q000473:pathology
chemical_list: D007070:Immunoglobulin A; D006632:Histamine