Direct immunofluorescence of perilesional skin from a patient with pemphigus shows deposition of IgG and C3 in which pattern?

• A Granular deposits along the basement membrane zone
• B Intercellular reticular staining throughout the epidermis ✓
• C Linear band at the dermoepidermal junction
• D Fibrillar staining of the papillary dermis

Explanation

Pemphigus is an intraepidermal blistering disease caused by IgG against desmosomal cadherins, so immunofluorescence shows the characteristic intercellular reticular or fishnet pattern of IgG and C3 within the epidermis. A linear band at the basement membrane zone is the pattern of bullous pemphigoid, epidermolysis bullosa acquisita, and linear IgA disease, while granular basement membrane deposits are typical of lupus band.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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