Bullous pemphigoid: Three main clusters defining 3 outcome profiles

Abstract

Bullous pemphigoid (BP) is the most common autoimmune blistering disorder. Its presentation is polymorphic. To investigate different clinical and biological profiles of BP. We conducted a retrospective 2-center study including all BP patients seen between January 1, 2015, and February 28, 2021. We performed hierarchical clustering on principal components. Three clusters were identified. Patients in cluster 1 (n=155) were older than those in clusters 2 (n=89) and 3 (n=35; P<.0001), more frequently presented pauci-bullous BP (n=63 [41%] vs 14 [16%] and 2 [6%], respectively; P<.0001) and had anti-BP230 antibodies in 87% of cases. More than 100 blisters were observed in 14 patients (40%) from cluster 3, versus 3 (2%) from cluster 1 and 0 (0%) from cluster 2 (P<.0001). Frequency of mucosal involvement was higher in cluster 3 (n=32 [91%, including epiglottis in 40%] vs 11 [7%] and 34 [38%]; P<.0001). In clusters 2 and 3, 70% and 74% of patients had antibodies targeting only BP180. Those in cluster 3 received more lines of systemic treatment and experienced more relapses. Retrospective study without immunoelectron microscopy. We identified 3 different BP clusters, including one corresponding to severe BP180+ BP230- BP with features common to mucous membrane pemphigoid.