Female Patients with Dermatitis Herpetiformis Show a Reduced Diagnostic Delay and Have Higher Sensitivity Rates at Autoantibody Testing for Celiac Disease

OBJECTIVE: Our objective was to characterize the demographic information, clinical features, and laboratory data of patients with dermatitis herpetiformis (DH). METHODS: In this multicentre cross-sectional study, consecutive patients with a new diagnosis of DH that referred to nine different Italian centers between 2011 and 2016 were characterized assessing demographic, clinical and laboratory findings, and evaluating gender and age differences across selected variables. RESULTS: A total of 151 patients were included. Among them, 81 (53.6%) were males and 70 (46.4%) were females, with a male to female ratio of 1.2 : 1. The median age at the time of diagnosis was 41 years (range 0–85). Males had a significant longer diagnostic delay if compared to females (9 vs. 3 months, respectively; p = 0.01). Direct immunofluorescence was positive in 94.7% of the patients, while duodenal biopsy showed partial to total villous atrophy in 70.1% of patients. All the females resulted positive to at least one of the antibodies tested, while a total of 12 male patients (10.5%) tested negative to celiac-specific antibodies. Female patients had a high rate (14.1%) of autoimmune thyroiditis. CONCLUSIONS: Our study confirmed some of the most relevant data regarding DH that have been previously reported in the literature. In addition, we found a reduced diagnostic delay in females with respect to males, possibly related to the higher sensitivity of serologic testing in females with DH compared to males. Finally, we demonstrated that intestinal involvement could be severe in patients with DH and that females should be tested for thyroiditis.