Clinical challenges and recent advances in the diagnosis of bullous pemphigoid

Bullous pemphigoid (BP) is an autoimmune subepidermal blistering disease associated with autoantibodies directed against two components of junctional adhesion complexes in stratified epithelia, BPAG2 and BPAG1-e. BP typically develops in the elderly and manifests with widespread eczematous, urticated and bullous lesions. In up to 20% of the affected patients, obvious blistering is lacking and the clinical features of BP are misleading and closely mimic a variety of other inflammatory conditions. Diagnosis of BP, which should be rather called cutaneous pemphigoid, relies on direct immunofluorescence microscopy studies to detect tissue-bound IgG and/or C3 immune deposits along the epidermal basement membrane zone. Here, the clinical presentations of BP and the diagnostic algorithm with the immunopathological studies available to classify affected patients are reviewed. Finally, the need for widely accepted criteria for the classification of BP patients is emphasized, since in a number of patients with featu...