The correct answer is B. Only 20% of patients have a gluten-sensitive enteropathy.
All of the statements regarding dermatitis herpetiforms, or “Duhring’s Disease,” are true except for statement B. Virtually all DH patients have gluten-sensitive enteropathy, although only 20% of them have symptoms (such as diarrhea, steatorrhea, weight loss, bloating, and malabsorption).
Dermatitis herpetiformis (DH) is a cutaneous manifestation of gluten sensitivity. Although over 90% of DH patients have evidence of a gluten-sensitive enteropathy, only about 20% have intestinal symptoms of celiac disease (CD). Both the skin disease and the intestinal disease respond to gluten restriction and recur with institution of a gluten-containing diet.
Circulating IgA antibodies to TG2 (an endomysial antigen) have been identified by indirect immunofluorescence microscopy using a monkey esophagus substrate, and the presence of these antibodies correlates with the degree of gluten-sensitive enteropathy. IgA anti-TG2 antibodies are not responsible for the IgA deposition in skin.
There is a strong genetic association with the HLA genotype DQ A1*0501, B1*02 (which encodes HLA-DQ2 heterodimers), in addition to other unidentified non-HLA genes.
A strong association exists between DH and thyroid disease, particularly Hashimoto thyroiditis. In one study, the presence of some type of thyroid abnormality was found in 26 of 50 patients with DH. Although the pathogenetic relationship between DH and thyroid disease is unknown, it may represent a coexistence of autoimmune disease.
The endomysial antigen has been identified as TG2, and antibodies directed against transglutaminase are important in the pathogenesis of DH and CD.