Analysis of desquamative gingivitis using direct immunofluorescence in conjunction with histology.

Chronic desquamative gingivitis (DG) is a common condition often first recognized by periodontists. DG is characterized clinically by erythema with epithelial desquamation, ulceration, and/or the presence of vesiculobullous lesions of the free and attached gingiva. However, DG is actually a clinical manifestation of several different disease processes, particularly lichen planus and benign mucous membrane pemphigoid. Correct diagnosis in DG is critical since proper treatment and follow-up will depend on which disease is involved. However, the diseases that cause DG frequently present diagnostic problems because their lesions often resemble each other clinically and routine histological examination sometimes cannot differentiate between them. Thus, immunohistology, particularly immunofluorescence, is increasingly being used with routine histology to more accurately diagnose DG diseases. This article reviews our experience over the past 10 years in the diagnosis of 72 cases of DG using direct immunofluorescent (DIF) in conjunction with histology and clinical evaluation. Of the 72 DG cases in this study, 30 cases were diagnosed as erosive lichen planus or lichenoid mucositis; 29 cases were diagnosed as benign mucous membrane pemphigoid; 2 cases each of linear IgA disease and pemphigus vulgaris were diagnosed; there was 1 case of bullous pemphigoid; and 1 suspected case of paraneoplastic pemphigus. Even with DIF analysis, 7 cases could not be definitively assigned a particular cause. DIF analysis is not only proving very useful for differential diagnosis, but also adds insight into possible pathogenic mechanisms of DG.