Dermatitis herpetiformis is confirmed by direct immunofluorescence showing IgA deposits in which skin layer?

Dermatitis herpetiformis is confirmed by direct immunofluorescence showing IgA deposits in which skin layer?

• A. Dermal-epidermal junction
• B. Papillary dermis
• C. Subcutaneous tissue
• D. Epidermis

Answer: (B)

Dermatitis herpetiformis shows granular IgA deposits in the dermal papillae, i.e., the papillary dermis just beneath the epidermis. This specific location on direct immunofluorescence matches the characteristic eruption and helps distinguish it from conditions with deposits at the dermal-epidermal junction (like linear IgG at the basement membrane) or deeper tissues.

Dermatitis herpetiformis shows granular IgA deposits in the dermal papillae, i.e., the papillary dermis just beneath the epidermis. This specific location on direct immunofluorescence matches the characteristic eruption and helps distinguish it from conditions with deposits at the dermal-epidermal junction (like linear IgG at the basement membrane) or deeper tissues.