Celiac disease and bone.

Celiac disease (CD) is an autoimmune disorder characterized by small intestinal inflammation triggered by gluten ingestion in genetically-predisposed individuals. A frequent extra-intestinal manifestation of CD is metabolic bone disease which contributes to an increased risk of fracture. The mechanisms underlying bone disease in CD remain incompletely understood, but multiple processes have been proposed including (1) malabsorption of calcium and vitamin D leading to secondary hyperparathyroidism and increased skeletal resorption, (2) pro-inflammatory cytokines altering the osteoprotegerin and receptor activator of nuclear kappa-B ligand ratio favoring osteoclastogenesis, (3) hypogonadism, and (4) low weight and malnutrition. Most studies show reduced bone mineral density in patients with CD. Bone microarchitecture is also deteriorated leading to reduced whole bone stiffness. Many, but not all investigations, have shown an increased risk of fracture associated with CD. The main stay of therapy for CD is maintaining a gluten-free diet. Improvement in bone mineral density with adherence to a gluten-free diet has been well-established. Bone mineral density remains lower, however, compared to controls and increased fracture risk can persist. There is no consensus on the timing of dual-energy x-ray absorptiometry for bone mineral density assessment in patients with CD. Routine screening for CD in patients with osteoporosis is not recommended. Little data are available on the use or efficacy of prescription osteoporosis therapeutics in patients with CD. Studies are needed to develop standardized guidelines for screening and treatment of metabolic bone disease in patients with CD to identify those who may need early intervention with prescription osteoporosis therapy.