Predicting bone loss following orthotopic liver transplantation

Background-Hepatic osteodystrophy occurs in the majority of patients with a dvanced chronic liver disease with the abnormalities in bone metabolism acc elerating following orthotopic liver transplantation (OLT). Aims-To examine changes in bone mineral density (BMD) following OLT and to investigate factors that lead to bone loss. Methods-Twelve patients had BMD (at both the lumbar spine (LS) and femoral neck (FN)) and biochemical markers measured preoperatively and for 24 month s following OLT. Results-BMD was low in 75% of patients prior to OLT and decreased significa ntly from baseline at the LS at three months and the FN at six months. BMD began to increase thereafter at both sites, approaching baseline values at the LS by 12 months. Bone formation markers, osteocalcin and procollagen ty pe I carboxy propeptide, decreased immediately post-OLT, with a concomitant increase seen in the resorption markers pyridinoline and deoxypyridinoline . This resulted in a negative uncoupling index early post-OLT, that rebound ed to positive values after six months. There was a significant correlation between the change in the uncoupling index between six and three months wh ich preceded the increase in BMD at 12 months. The decrease in BMD recorded early post-OLT correlated with vitamin D levels at three months. Conclusions-Results suggest that increased resorption and inadequate format ion are the major contributors to additional bone loss following OLT. Nonin vasive biochemical markers precede later changes in BMD in this patient gro up following OLT and may have a role in investigating and planning interven tion strategies to prevent bone loss in future studies.