Dermatitis herpetiformis
Overview
Plain-Language Overview
Dermatitis herpetiformis is a chronic skin condition that causes intensely itchy, blistering rashes. It primarily affects the skin, especially on the elbows, knees, back, and buttocks. This condition is linked to an immune reaction triggered by eating gluten, a protein found in wheat, barley, and rye. The immune system mistakenly attacks the skin, leading to the formation of small blisters and red bumps. People with this condition often have an underlying sensitivity to gluten called celiac disease, which affects the digestive system. The rash can cause significant discomfort and may come and go over time. Managing the condition involves addressing the immune response and avoiding gluten.
Clinical Definition
Dermatitis herpetiformis is a chronic, autoimmune blistering disorder characterized by IgA deposition in the dermal papillae, resulting in a pruritic, vesicular rash. It is strongly associated with gluten sensitivity and is considered a cutaneous manifestation of celiac disease. The pathogenesis involves the formation of IgA antibodies against tissue transglutaminase and epidermal transglutaminase, leading to immune complex deposition and neutrophil recruitment in the skin. Clinically, it presents with symmetrical, grouped vesicles and papules on extensor surfaces. Diagnosis is important due to the risk of associated malabsorption and lymphoma in untreated celiac disease. The condition typically responds to a gluten-free diet and dapsone therapy.