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What is Subepidermal blisters with granular deposits of IgA selectively localized to the tips of dermal papillae is a feature of- and explain in detail?
Histologically, the early lesions of dermatitis herpetiformis consist of neutrophilic micro-abscesses at the tips of papillae, producing separation or blister between the papillary dermis and the epidermis. The older blisters contain a fair number of eosinophils causing confusion with bullous pemphigoid. Direct immunofluorescence shows granular deposits of IgA at the papillary tips in dermatitis herpetiformis. Ref: Textbook of pathology by Harshmohan 6th edition page 777.