Assessment of the Prevalence of Mucosal Involvement in Bullous Pemphigoid.

Importance: The prevalence of mucosal involvement in bullous pemphigoid (BP) is inconsistent. Nonoral mucosal involvement was reported anecdotally in few patients with BP. Objective: To evaluate the prevalence of mucosal involvement in patients with BP, and to characterize the subgroup of patients with mucosal lesions. Design, Setting, and Participants: A retrospective cohort study was performed including 328 consecutive patients diagnosed with immunopathologically validated BP at a tertiary care referral center for autoimmune bullous diseases in northern Israel between January 1, 2000, and December 31, 2017. Main Outcome and Measures: The study was conducted to estimate the prevalence and distribution of mucosal involvement among patients with BP. Patients with mucosal involvement were compared with the remaining BP patients regarding clinical and immunological features, laboratory analyses, and treatments. Results: The study cohort included 139 (42.4%) male and 189 (57.6%) female patients, with a mean (SD) age of 78.0 (11.8) years at presentation. Fifty-six patients (17.1%) presented with mucosal lesions. The oral mucosa was the most frequently affected mucosal surface (n = 44; 13.7%), followed by the laryngeal (n = 16; 4.9%) and the genital (n = 10; 3.0%) mucosae. Among patients with oral lesions, the most involved oral structures were the buccal mucosa (n = 25; 55.6%) and the soft palate (n = 24; 53.3%). Compared with other patients with BP, patients with mucosal involvement were younger (71.8 [14.4] years vs 79.3 [10.8] years; P < .001), presented more frequently with extensive disease (55.4% vs 39.7%; P = .002), had less peripheral eosinophilia (17.8% vs 41.9%; P < .001), and were treated with higher doses of corticosteroids (prednisone >1 mg/kg: 67.9% vs 51.8%; P = .03). Conclusions and Relevance: Mucosal lesions are present in a notable subgroup of patients with BP and are associated with disease severity. Laryngeal involvement is more common than previously appreciated.