Assessment of bone mass following renal transplantation in children

Throughout childhood and adolescence, skeletal growth results in site-specific increases in trabecular and cortical dimensions and density. Childhood osteoporosis can be defined as a skeletal disorder characterized by compromised bone strength predisposing to an increased risk of fracture. Pediatric renal transplant recipients have multiple risk factors for impaired bone density and bone strength, including pre-existing renal osteodystrophy, delayed growth and development, malnutrition, decreased weight-bearing activity, inflammation, and immunosuppressive therapies. Dual energy X-ray absorptiometry (DXA) is the most-common method for the assessment of skeletal status in children and adults. However, DXA has many important limitations that are unique to the assessment of bone health in children. Furthermore, DXA is limited in its ability to distinguish between the distinct, and sometimes opposing, effects of renal disease on cortical and trabecular bone. This review summarizes these limitations and the difficulties in assessing and interpreting bone measures in pediatric transplantation are highlighted in a review of select studies. Alternative strategies are presented for clinical and research applications.