Unlike osteopenia and osteoporosis which are defined by the World Health Organization (WHO) using DXA T-scores, there is no WHO definition for high (supranormal) bone mineral density. Hence most authors classify it based upon the Z-score, which is based upon comparison to individuals of the same gender, age, race/ethnicity, and height/weight. A Z-score of >=2.5 is considered abnormal by many authors and termed high bone mineral density.

The differential for diffuse high bone mineral density is different from focal high bone mineral density, and also varies between adults and children. Given this patient's history of chronic kidney disease and hypercalcemia, this case is presumed to represent renal osteodystrophy.