Dermatitis Herpetiformis (Duhring's Disease)
Dermatitis herpetiformis lesions consist of extremely itchy, tense, grouped herpetiform vesicles usually 3 to 6 mm in diameter and occurring in a distinctive distribution over the elbows, knees, buttocks, upper back, and posterior scalp. Because of excoriation, round crusts are often the only visible sign of the disease. The gold standard for diagnosis is biopsy with direct immunofluorescence of lesional or normal skin showing IgA deposits, usually in a granular pattern at the tips of dermal papillae. About 90% of patients will have evidence of gluten-sensitive enteropathy on small-bowel biopsy.
