Transplantation Bone Alterations in Children and Young Adults With Renal Transplant Assessed by Phalangeal Quantitative Ultrasound Alessandro Mussa, MD, 1 Francesco Porta, MD, 2 Bruno Gianoglio, MD, 3 Maurizio Gaido, MD, 3 Mario Guido Nicolosi, MD, 4 Francesca De Terlizzi, PhD, 5 Carlo de Sanctis, MD, 1 and Rosanna Coppo, MD 3 Background: Bone alterations in young renal transplant recipients were investigated in several studies with conflicting results. Quantitative ultrasound of the phalanges is a recently developed noninvasive procedure to assess skeletal status. Study Design: Cross-sectional study at a single transplant center with values compared with previously studied healthy controls. Settings & Participants: 40 children and young adult recipients of renal grafts (15 females, 25 males; age, 20.0  8.4 years) studied 7.1  3.8 years after kidney transplantation. Predictor: Clinical, biochemical, and therapeutic features, including calcium, phosphate, and intact parathor- mone levels; and cumulative dosages of glucocorticoids and cyclosporine administered since transplantation. Outcome & Measurement: Phalangeal quantitative ultrasound, including amplitude-dependent speed of sound (AD-SoS) and bone transmission time (BTT), mainly dependent on mineral density and cortical thickness, respectively. Age- and sex-matched healthy controls were used to provide age- related z scores; sex- and height-matched healthy subjects, to provide z scores related to statural age. Results: Mean z scores of AD-SoS and BTT were -0.05  1.59 and -0.54  1.17, respectively (P  0.05 and P  0.001, respectively). Multivariate analysis showed that AD-SoS z score was associated significantly with body mass index, intact parathormone level, cumulative glucocorticoids administered in the first posttransplantation year, and cyclosporine administered since transplantation (model r 2 = 0.79; P  0.001); BTT z score was associated significantly with glucocorticoid dosage in the first posttransplantation year and age (model r 2 = 0.55; P  0.001). Limitations: Absence of other measures of bone structure and longitudinal measures and compari- son to a noncurrent control group. Conclusions: Children and young adults may have decreased cortical thickness with maintained overall mineral density after renal transplantation. The findings of phalangeal quantitative ultrasound parallel observations using other imaging techniques. Phalangeal quantitative ultrasound may be a useful method to assess bone alternations after renal transplantation. Am J Kidney Dis 50:441-449. © 2007 by the National Kidney Foundation, Inc. INDEX WORDS: Bone; bone density; kidney transplantation; quantitative ultrasound; renal osteodystrophy. D uring the last years, attention has focused on the evaluation of skeletal mineralization in childhood and young adulthood because the bone mass attained in the first 2 decades of life currently is seen as the most relevant factor for lifelong skeletal health. 1,2 Because the renal transplant sur- vival rate is steadily improving, several studies drew attention to the possible skeletal complica- tions of kidney transplantation and immunosuppres- sion in young kidney transplant recipients, such as osteoporosis, spontaneous fractures, growth fail- ure, and avascular necrosis. To date, several factors were identified as negatively affecting skeletal sta- tus in young renal graft recipients. Chronic renal failure with impaired vitamin D metabolism and secondary hyperparathyroidism lead to renal os- teodystrophy; after transplantation, these factors improve substantially, but patients are exposed to residual hyperparathyroidism and immunosuppres- From the 1 Department of Pediatric Endocrinology, Re- gina Margherita Children’s Hospital; 2 Department of Pedi- atrics, University of Torino; 3 Department of Pediatric Nephrol- ogy, Regina Margherita Children’s Hospital; 4 Department of Gynecology and Obstetrics, S. Anna Hospital, Torino; and 5 Igea Biophysics Laboratory, Carpi, Modena, Italy. Received January 8, 2007. Accepted in revised form June 4, 2007. Originally published online as doi: 10.1053/j.ajkd.2007.06.002 on August 2, 2007. Address correspondence to Alessandro Mussa, MD, De- partment of Pediatric Endocrinology, Regina Margherita Children’s Hospital, Piazza Polonia 94, 10126, Torino, Italy. E-mail: mussa_alessandro@yahoo.it © 2007 by the National Kidney Foundation, Inc. 0272-6386/07/5003-0014$32.00/0 doi:10.1053/j.ajkd.2007.06.002 American Journal of Kidney Diseases, Vol 50, No 3 (September), 2007: pp 441-449 441