Association Between Disease Severity and Clinical, Histopathological, and Eosinophilic Markers in Patients With Bullous Pemphigoid (BP-EPIC)

Bullous pemphigoid is an autoimmune subepidermal blistering disease characterized by eosinophilic inflammation and variable disease severity. This retrospective observational study aims to evaluate the relationship between disease severity and histopathological features, serum IgE levels, peripheral eosinophil counts, and the expression of eosinophilic cationic protein (ECP) and periostin in skin biopsy specimens of patients with bullous pemphigoid. Immunohistochemical staining for ECP and periostin will be assessed semi-quantitatively and correlated with clinical and laboratory parameters, including BPDAI scores, eosinophil counts, serum IgE levels, hospitalization history, and disease relapse. The study seeks to identify potential tissue biomarkers associated with disease activity and severity in bullous pemphigoid.