Definition and classification of renal osteodystrophy and chronic kidney disease–mineral bone disorder (CKD–MBD)

Mineral and bone disorders are complex abnormalities that cause morbidity and mortality in patients with CKD. In order to raise awareness of the systematic manifestations of mineral and bone disorders, KDIGO established a new term ‘chronic kidney disease–mineral and bone disorder’ (CKD–MBD) to describe the syndrome of biochemical, bone, and extra-skeletal calcification abnormalities that occur in patients with CKD. The term renal osteodystrophy should be used exclusively to define alterations in bone morphology associated with CKD, assessed by bone biopsy with or without histomorphometry. The results of the biopsies should be reported based on a classification system that includes parameters of turnover, mineralization, and volume. These updated definitions, and classification schemes of these two disorders due to CKD reflect new scientific advances, and the adoption of this terminology should further enhance research and improve patient care.