Mucosal involvement is a risk factor for poor clinical outcomes and relapse in patients with pemphigus treated with rituximab.

Many studies have reported the outcome of rituximab use in pemphigus but studies regarding the clinical risk factors for poor clinical outcomes or relapse are lacking. To clarify the risk factors for poor clinical outcomes or relapse in patients with pemphigus treated with rituximab, a retrospective chart analysis was performed on patients with pemphigus who were treated with rituximab in the dermatology clinic of Seoul National University Hospital. Forty patients with pemphigus were treated with rituximab, of which 39 (97.5%) experienced remission and 19 (48.7%) experienced relapse. Patients with mucosal lesions demonstrated poor clinical outcomes. The risk for relapse was 4.626 (confidence interval: 1.126-19.001, p = .034) times higher in patients with mucosal lesions than in those without lesions. In patients with pemphigus treated with rituximab, the presence of mucosal lesions resulted in poor clinical outcomes and frequent recurrence.