Bone metabolism and gonad function in male patients undergoing liver transplantation: a two-year longitudinal study

Osteodystrophy is a major complication of end-stage liver disease, especially in postmenopausal women. Our aim in this study was to evaluate bone metabolism and gonad function in men undergoing orthotopic liver transplantation (OLTx). Twenty-three consecutive men (mean age 48±13 years) evaluated for OLTx were studied, assessing the following parameters at baseline and 3, 6, 12 and 24 months after OLTx: lumbar spine (L2-L4) bone mineral density (BMD), parathyroid hormone (PTH), osteocalcin (BGP), 25-hydroxyvitamin D (25OHD), free testosterone (FT) and gonadotropins (FSH, LH). At baseline, 12 patients (52%) had a T-score<-2.5 SD and the mean BMD was 0.806±0.11 g/cm2 (range 0.470-1.045 g/cm2). The BMD was lower 3 months after OLTx and significantly higher 12 and 24 months after OLTx. A significant increase in serum BGP was observed at 6, 12 (p<0.05) and 24 months (p<0.005) after OLTx. The mean serum PTH level was 26.6±3.1 pg/ml at baseline and increased significantly at 12 and 24 months (to 49.4±9.9 and 61.2±10.1 pg/ml, respectively; p<0.05). 25OHD serum levels were low at baseline and returned to the normal range after 12 and 24 months (baseline, 8.73±1.54 ng/ ml; 12 months, 16.4±2.6 ng/ml; 24 months, 17.67±3.1 ng/ml; p<0.05). FT was significantly lower at baseline than in a group of 10 healthy controls (5.09±10.99, vs 10.3±1.1 pg/ml; p<0.0001). After OLTx a significant increase in FT was recorded at 6, 12 (p<0.05) and 24 months (p<0.005). FT was not correlated with BMD, however. After OLTx an increase in FSH and LH was observed (but failed to reach statistical significance) at 3 and 6 months, followed by a slight reduction at 12 and 24 months. Thus a high proportion of men with end-stage liver disease do have osteoporosis. After OLTx, an early recovery of gonad function is observed, followed by an increase in bone mass, which occurs from the sixth month onward.