Bullous Pemphigoid

A 68-year-old man presents with tense, fluid-filled bullae on the flexural surfaces of the forearms and inner thighs. Histopathology shows subepidermal blistering with intact basal layer. Which is the most common site of involvement in bullous pemphigoid?

Which is the most common age group affected by bullous pemphigoid?

A 68-year-old man presents with tense, fluid-filled blisters on the flexural surfaces of both forearms and inner thighs for 3 weeks. On examination, the blisters are intact, do not rupture easily, and the surrounding skin is erythematous. Direct immunofluorescence shows linear IgG and C3 deposits along the basement membrane zone. What is the most appropriate next step in management?

Which single histopathological feature best distinguishes bullous pemphigoid from pemphigus vulgaris?

A 62-year-old man presents with tense bullae on the flexural aspects of forearms and inner thighs for 3 weeks. Clinical examination reveals intact bullae that do not rupture easily. Nikolsky sign is negative. Which investigation is most specific for confirming the diagnosis of bullous pemphigoid?