Endocrinology of bone mineralization: An update

• Published in: Annales d'endocrinologie 2022-02, Vol.83 (1), p.46-53
• Main Authors: Jannin, A., Kerlan, V., Desailloud, R.
• Format: Article
• Language: English
• Subjects: Bone; Hypophosphatasia; Hypophosphatasie; Hypophosphatemia; Hypophosphatémie; Inhibiteurs de la sclérostine; Lacune thérapeutique; Osteomalacia; Osteoporosis; Ostéomalacie; Ostéoporose; Sclerostin inhibitors; Treatment gap
• ISSN: 0003-4266
• DOI: 10.1016/j.ando.2021.12.001

Throughout the world, millions of people suffer from fragilizing osteopathies such as osteomalacia and osteoporosis. Osteomalacia is a rare disorder, corresponding to mineralization abnormalities in adult bone, as opposed to rickets in children. Renal phosphate loss and hypophosphatasia are the main causes of vitamin-resistant osteomalacia. Diagnosis is based on clinical history, phosphocalcic metabolism assessment and, if necessary, molecular characterization, and must be rapid in order to initiate the most appropriate treatment and consider new treatments such as burosumab if necessary. Osteoporosis is characterized by reduced bone mass and strength, which increases the risk of fragility fracture. Fracture-related burden is expected to increase over the coming decades linked to the aging of population and a treatment gap. In order to reduce this treatment gap, it is important to develop two strategies: improvement of screening and of treatment. Systematic screening using the FRAX® fracture risk assessment tool could be useful to increase anti-osteoporosis medical treatment and reduce fracture rates. The question of treatment sequencing in osteoporosis is another challenge, notably after denosumab cessation, complicated by a decrease in bone mineral density and increased risk of fracture. New treatments are also available, including romosozumab, a humanized monoclonal antibody, which promotes bone formation and inhibits bone resorption by inhibiting sclerostin. Romosozumab is approved in several countries, including France, for treating severe osteoporosis in postmenopausal women at high risk of fracture and free of cardiovascular comorbidity. Endocrinologists need to be aware of these fragilizing osteopathies in order to improve both diagnosis and treatment. De partout le monde, des millions de personnes souffrent d’ostéopathies fragilisantes telles que l’ostéomalacie ou l’ostéoporose. L’ostéomalacie est une maladie rare, qui correspond à des anomalies de la minéralisation osseuse chez l’adulte, à la différence du rachitisme de l’enfant. La perte rénale de phosphate et l’hypophosphatasie sont les causes principales de l’ostéomalacie résistante aux vitamines. Le diagnostic s’appuie sur l’anamnèse clinique, l’évaluation du métabolisme phosphocalcique et, si nécessaire, la caractérisation moléculaire. Il doit être effectué rapidement pour permettre l’initiation d’un traitement optimal, prenant en compte les nouvelles thérapies telles que le burosumab si bes