Bullous pemphigoid: epidemiological, clinical, and therapeutic analysis of 189 patients in a tertiary center in Brazil

Abstract

Background  Bullous pemphigoid (BP) is the most prevalent autoimmune bullous dermatosis with increasing incidence globally. There is a lack of literature on BP in the multiethnic Brazilian population.

Objectives  To assess the epidemiological, clinical, and therapeutic characteristics of BP patients in a tertiary center in Brazil.

Methods  Retrospective longitudinal review of clinical records of 189 BP patients from January 1986 to September 2023.

Results  BP primarily affected elderly individuals, predominantly females, with an average onset of symptoms at 65.7-years. Non-bullous presentations had a longer time to diagnose compared to the bullous form. Mucosal involvement was observed in 24.9% of patients. Subepidermal blistering was the predominant histopathological feature. Most cases presented fluorescence of IgG and C3 at the basement membrane zone (BMZ) on direct immunofluorescence. Indirect immunofluorescence mainly revealed fluorescence of IgG along the BMZ, and with salt-split skin technique demonstrated predominantly IgG fluorescence on the epidermal side of the cleavage. Eosinophilia, elevated IgE levels, and D-dimer were common. Systemic corticosteroids remained the mainstay of treatment. BP was associated with significant complications, including thromboembolism, hospitalization, and infections, along with numerous comorbidities and a notable percentage (10.6%) of patients using potentially BP-inducing medications.

Study limitations  The study's limitations include its retrospective design, reliance on potentially incomplete clinical records, and findings of a single tertiary center.

Conclusions  This study provides crucial insights into the multifaceted nature of BP in the Brazilian population, emphasizing the need for comprehensive management strategies to address its diverse complications and associated conditions.

Keywords
Autoimmune diseases; Brazil; Bullous pemphigoid