 The present study will be performed in children with growth retardation related to long-term glucocorticoid treatment These patients had never been treated with GH. In order to be able to evaluate the effect of GH on the muscle a comparative group is needed. Therefore it will be proposed in the study to delay in a group of patient the start of GH treatment by 6 months. Six months should be enough to evaluate short-term effect of GH on the muscle and most publication have shown a maximum effect of GH within the first year of treatment. Therefore, this study will be a randomized trial: immediate start of GH treatment versus start of GH treatment 6 months later. After 6 months all children will be treated with GH. The dose administered in the present trial will be a GH dose already tested in glucocorticoid treated children 0.46 mgkgweek 