Dermatitis herpetiformis and bone mineral density: analysis of a French cohort of 53 patients.

The characteristics of patients with dermatitis herpetiformis (DH) in France is poorly documented. Furthermore, the risk of fractures and bone mineral density (BMD) in DH remain under-described, and recommendations for systematic screening for osteoporosis in DH are lacking. To describe the characteristics of DH in a large French cohort and evaluate the association between BMD and features of osteoporosis. Patients were recruited from the French Association of Gluten Intolerants (AFDIAG) and a single university dermatology department. A telephone questionnaire was used to record features of DH, history of fractures, calcium intake, treatment, and the gluten-free diet (GFD). Serum calcium and 25(OH) vitamin D3+D2 levels, as well as BMD, were measured. We included 53 patients (27 men) with a median age of 49 years (range: 23-86). Median disease duration before inclusion was 14 years (range: 2-55); 51 patients (96%) were adherent to a GFD and had no digestive symptoms. Overall, 18 (34%) had a history of fractures; 16 high-velocity (traumatic) and two low-velocity (non-traumatic). Mean BMD, measured in 48 patients, was normal (femoral neck: 0.956 ± 0.210 g/cm; lumbar spine: 1.091 ± 1.199 g/cm). In all, 18 patients (38%) had osteopenia and one (2%) osteoporosis. T-score for bone density did not differ with and without fractures. Calcium intake and serum calcium level were normal in all patients. Screening for osteoporosis does not appear to be mandatory for DH patients with good adherence to a GFD and without digestive symptoms or additional risk factors of osteoporosis.