When started in adolescence, GH treatment significantly improves AH in short SGA children, particularly with GH 2 mg/m(2) · d during puberty. When SGA children are short at the start of puberty, they can benefit from combined GH/GnRHa treatment.

Leprechaunism is an inherited human disorder characterized by severe insulin resistance. We have examined the properties of the insulin receptor in fibroblasts from a leprechaun patient. In vitro, severe insulin resistance is reflected by a low level of insulin binding to the patients fibroblasts and impaired insulin-mediated uptake of 2-deoxyglucose. Quantification of the receptor in detergent-solubilized total glycoprotein indicates a normal receptor number, in agreement with the observed normal level of insulin receptor mRNA on northern blots. The insulinstimulated autophosphorylation of the patient's receptor shows a normal profile. The insulin receptor is present on the plasma membrane as indicated by cell-surface iodination experiments. No abnormalities in the molecular masses of the receptor's M and p chains were observed. The results indicate that an apparently normal receptor is synthesized in sufficient amounts but functional expression of the receptor on the plasma membrane is impaired.