Validation of a Simplified Severity Score (Investigator Global Assessment: IGA) in Bullous Pemphigoid

Inclusion Criteria: * Consecutive adult patients aged ≥ 18 years * Newly diagnosed or relapsing BP * Clinical features suggestive of classic BP AND suggestive histological features AND deposition of IgG and/ or C3 deposits on the dermal epiderma junction, AND detection of circulating anti-epidermal antibodies labelling the epidermal side of salt-split skin * Patient having read and understood the information letter and not opposed to participation * Must be willing and able to adhere to all specified requirements, including but not limited to adherence to the follow-up visits Exclusion Criteria: * Predominant or exclusive mucosal involvement leading to suspect the diagnosis of mucous membrane pemphigoid * Pemphigoid gestationis * Linear IgA dermatosis (predominant or exclusive IgA deposits on the DEJ) * Skin lesions suggesting the diagnosis of epidermolysis bullosa acquisita (skin fragility, atrophy, milia)