Dermal IgA Deposition Targeted Against Transglutaminase 3 in Dermatitis Herpetiformis Risk Groups

This study investigated dermal IgA deposition in Dermatitis herpetiformis (DH) risk groups, including 17 celiac disease (CD) patients and 68 first-degree relatives of DH/CD patients, compared to 16 DH and 37 dermatological controls. Dermal IgA deposition was rare in CD patients and their relatives, with only one CD patient and one relative showing deposition without skin symptoms or serum TG3 antibodies. Co-localization of IgA with TG3 was not observed in non-DH subjects, while all DH controls showed co-localization and 56% had serum TG3 antibodies. The study suggests that dermal IgA deposition without DH symptoms is uncommon in DH risk groups, and recommends serial staining and co-localization studies for DH exclusion in ambiguous cases.