IGF-I and IGF Binding Protein-3 Generation Tests and Response to Growth Hormone in Children with Silver-Russell Syndrome

Objectives. To evaluate, in children with Silver-Russell Syndrome, the response to the IGF-I and IGFBP-3 generation test and compare results to the growth response after 6 months of rhGH. Methods. Eight children (6 males), with a mean age of 5.71 ± 2.48 years and height SDS of -3.88 ± 1.28 received rhGH for 6 months. IGF-I and IGFBP-3 were analyzed before and after 4 doses of rhGH. Results. The mean growth velocity (GV) before treatment was 5.28 ± 1.9 cm/year. GV increased after rhGH in five children to a mean GV of 10.3 ± 3.64 cm/year. Six children had normal basal IGF-I levels and two low levels. After 4 doses of rhGH, the IGF-I levels were normal in seven. There was no correlation between the growth response and the IGF-I generation test. Conclusions. Children with SRS have normal IGF-I generation test. There is no correlation between the generation test and the growth velocity after 6 months of rhGH.