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

Abstract

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.

Russell Silver syndrome: a perspective on growth and the influence of growth hormone therapy

“…The growth in the first three years of life is slow, and from this point on it remains parallel to the curve but below the third percentile. [ 3 ] The average adult height attained, without GH therapy, is 151.2 cm (-7.8 SD) in males and 139.9 cm (-9 SD) in females. [ 4 ] They also have characteristics of abnormal growth hormone pulsatility, absence of catch-down growth after growth hormone therapy and inappropriate advancement of bone age during the middle childhood years.…”