[Somatomedin activity and growth hormone secretion in children with idiopathic growth retardation (author's transl)].

Somatomedin activity, as estimated by the porcine bioassay and GH response to stimulation were compared in prepubertal children with severe growth retardation and lack of evidence of pituitary dysfunction. Somatomedin activity was strongly correlated with growth rate. A group of patients had a low somatomedin activity in contrast with normal GH responsiveness. This appears to be a rather frequent situation and deserves further evaluation of the somatomedin system and a more critical approach of GH secretion.