Immunofluorescence microscopic studies of recurrent aphthous stomatitis.

Direct immunofluorescence microscopic techniques were used to identify immunoglobulins and complement in the oral biopsy specimens of 22 patients with recurrent aphthous stomatitis (RAS). Ten (45%) of 22 patients demonstrated fluorescence along the basement membrane zone, and vascular fluorescence was seen in seven patients. These findings are in agreement with those of previous immunofluorescence microscopic studies of RAS and suggest the possibility that circulating immune complexes may play a role in the tissue damage seen in this disease.