Linear IgA disease (LAD): immunoglobulin deposition in oral and colonic lesions.

Two cases of adult linear IgA disease (LAD) with oral and colonic involvement are presented. Oral findings, for both patients, were of widespread painful ulceration present for two to three months and diagnosis was confirmed by biopsy and direct immunofluorescence. Colonic symptoms preceded oral symptoms in both cases and a number of investigations were undertaken, including routine histological examination, which suggested either lymphocytic colitis or Crohn's disease. Immunofluorescence studies showed linear IgA deposition confined to the distal colon. These cases highlight that large bowel involvement can be a feature of linear IgA disease and for the first time demonstrate IgA deposition at that site.