**10. Conclusion**

ESLD results in a decline in liver production and deficiency of IGF-1, which impair GH bioavailability for peripheral tissues. This hormonal disorder leads to delayed growth in children with congenital cholestatic diseases.

Our studies have shown that children with ESLD have high GH and low IGF-1 levels, which is combined with growth failure and body mass deficit.

After pediatric LT, GH concentrations fall, while those of IGF-1 increase. As early as a month after LT, the plasma concentrations of both hormones do not differ from those in healthy children, and a year after the transplantation, they remain at normal levels.

After LT, the relationship between plasma GH and IGF-1 levels is restored, which was disrupted in children with ESLD.

Normalization of the ratio between serum levels of IGF-1 and GH a year after LT can serve as an integral indicator of the restoration of hormonal regulation of the physical development of pediatric recipients. A year after LT, GH and IGF-1 levels in pediatric recipients are comparable to those in healthy children.

GH bioavailability, mediated through IGF-1, is restored due to normal production of IGF-1 by the graft. The body height and body mass of pediatric recipients are also comparable to those of healthy children. This reflects the restoration of central and peripheral hormonal regulation of growth, which is a consequence of graft functioning.
