Retrospective study of gingival involvement in pemphigus: A difficult to treat phenomenon.

Pemphigus is a group of autoimmune diseases characterized by flaccid lesions on the skin and mucous membranes. In pemphigus vulgaris, the most common subtype of pemphigus, lesions might be appeared anywhere on the oral mucosa, mostly in the buccal mucosa. However, the gingiva is a less frequently affected site. Here, we performed a retrospective study at Tehran University of Medical Sciences, covering a two-year period to identify pemphigus patients with active lesions confined to the gingiva. Considering 1787 initially evaluated pemphigus cases, 512 (28.6%) were found to have a history of gingival involvement. Among them, 31 patients had only gingival involvement during their last visit, including 29 (93.5%) women and only two (6.5%) men. The mean of disease duration in this group was 5.29 ± 3.46 years, and they had gingival involvement for a mean of 23.9 ± 19.3 months. Of 28 patients, nine were negative for anti-Dsg3 and 24 were negative for anti-Dsg1. In 24 patients, who received rituximab, the mean pemphigus disease area index specifically for gingiva was 4.76 ± 0.74 at baseline, which had changed to 4.13 ± 0.75 and 3.26 ± 0.63 three and 6 months after rituximab administration, respectively. After 3 months, gingival lesions were either entirely resolved (n = 3), partially resolved (n = 11), remained unchanged (n = 2), or progressed (n = 7). Gingiva-confined presentation of lesions in pemphigus could be non-anti-Dsg1/3 dependent in some patients. Such patients do not respond well to conventional treatments and rituximab therapy. More studies on the pathogenesis of gingiva-confined presentation of pemphigus are required.