Inclusion Criteria:  Patients aged 18 or older Initiation of corticosteroids within 30 days prior to inclusion Estimated cumulative dosage of corticosteroids ≥ 2000 mg Affiliated member of the social security system  Exclusion Criteria:  Patients unable to give consent or unable to understand the protocol Patients under guardianship Previous exposure to long-term corticosteroids Prescription of corticosteroids for the management of malignant neoplasms Severe chronic renal failure with clearance of creatinine < 30 ml/min. History of organ transplantation Pregnant or breastfeeding women