A skin biopsy from a patient suspected of having Bullous Pemphigoid is sent for direct immunofluorescence (DIF). Which of the following findings would confirm the diagnosis?

Explanation

Direct immunofluorescence (DIF) is the gold standard for diagnosing Bullous Pemphigoid. It characteristically shows linear deposition of IgG and/or C3 along the dermal-epidermal junction. Intercellular IgG deposition in a 'chicken wire' pattern is typical for Pemphigus Vulgaris. Granular IgA deposition in the dermal papillae is characteristic of Dermatitis Herpetiformis. Perivascular IgA deposition in the superficial dermis is seen in IgA vasculitis (Henoch-Schönlein purpura) or other IgA-mediated vasculitides, not Bullous Pemphigoid.