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What is A 30-year-old male had severely itchy papulo–vesicular lesions on extremities, knees, elbows and buttocks for one year. Immunofluorescence staining of the lesions showed IgA deposition at dermo-epidermal junction. The most probable diagnosis is – and explain in detail?
Itchy papulovesicular lesions on extensor surfaces and deposition of IgA at DEJ suggests the diagnosis of dermatitis herpatiformis, which is associated with Coeliac disease