Changes in growth, growth hormone, and insulin-like growth factor-I (IGF-I) after orthotopic liver transplantation

Growth failure is an important consequence of chronic liver disease in childhood. Insulin-like growth factor-I (IGF-I), which is synthesized and released by the liver, plays an important role as a growth regulator in humans. We examined the growth hormone (GH)/IGF-I axis before and after orthotopic liver transplantation (LT) in 14 children aged between 2 and 11 years (mean 5.6 +/- 1.1 years). Pre-transplantation serum GH levels (7.5 +/- 1.2 ng/ml) were significantly higher (P < 0.001) compared with controls (5 +/- 0.5 ng/ml). However, post-transplantation levels (1.8 +/- 0.8 ng/ml) did not differ from those in the control group. Serum IGF-I levels showed a statistically significant increase after LT (20.1 +/- 9.4 vs 190 +/- 66.2 ng/ml; P < 0.001) and became indistinguishable from the levels in the control group (180 +/- 96 ng/ml). In comparison with pre-transplantation data (z - 2.70), there was an increase in height 4 years postoperatively (z - 1.68). Catch-up growth was highly significant, in particular during the 1st year after LT (z -1. 58 +/- 1.63 vs 2.59 +/- 5.29; P < 0.01). We conclude that a GH resistance state found in patients with severe chronic liver disease reverted following LT. Given that IGF-1 depends upon liver function, this could be one of the main factors in the significant catch-up growth in pediatric LT recipients.