The frequency and risk factors of low bone mineral density one year after liver transplantation in children: a study in Shiraz Organ Transplant Center

Abstract

Objective: Osteoporosis is a severe epiphenomenon that follows liver transplantation (LT). There is an inconsistency regarding risk factors of developing osteoporosis in LT children. In this article, we address the frequency of low bone mineral density (BMD) in LT children.

Methods: This is a prospective study performed on children aged <18 years old, referred to the Shiraz Organ Transplant Center. The study was conducted from March 2009 until March 2014. Those with at least one year passed from the transplantation were included. Lumbar and hip bone densities were checked by Dual-Energy Radiograph Absorptiometry.

Results: From the total of 84 included children, 32 (38.1%) and 52 (61.9%) were males and females respectively. The underlying diseases included cryptogenic (32, 28.1%), biliary atresia (18, 21.4%), Wilson disease (9, 10.7%), autoimmune hepatitis (9, 10.7%), tyrosinemia (6, 7.1%), acute liver failure (5, 6%), and hypercholesterolemia (5, 6%). Overall, 53 children (63.1%) had normal BMD, while 31 (36.9%) revealed lower than normal BMD. The means of lumbar and hip z scores were -1.04+/-1.47 (median of -0.75) and -0.98+/-1.92 (median of -0.60), respectively. There was no significant association between bone density and the age of transplantation, sex, weight, height, or underlying diseases (P>0.05). None of the immunosuppressive drugs were associated with low BMD. The patients who received pulse therapy showed a significantly higher rate of low BMD respective to the patients who did not receive pulse therapy (P=0.03).

Conclusion: The frequency of low BMD is relatively high in LT children. Pulse therapy may increase the risk of low BMD and osteoporosis in LT children.