Increased immunoreactive plasma and urinary growth hormone in growth retardation with defective generation of somatomedin a (Laron's Syndrome).
In a boy 4 years old with clinical hypopituitary dwarfism, high plasma and urinary levels of immunoreactive growth hormone were found. Somatomedin A levels in serum were low and failed to respond after short-term treatment with human growth hormone. The parents were first cousins. In the arginine and insulin tolerance tests the initially high immunoreactive growth hormone levels were later followed by a decrease to high normal values. Insulinopenic response was present during the arginine and glucose tolerance tests. As a growth hormone molecule defect is not found in these patients and no growth or other metabolic response to exogenous HGH can be demonstrated, it is concluded that a defective somatomedin generation may be present, probably in conjunction with a generalized receptor defect and deficient feedback system with abnormal release of HGH. The lack of somatomedin A is responsible for the severe growth retardation and the disturbance in carbohydrate metabolism is probably caused by sustained high growth hormone levels.
D002239:Carbohydrate Metabolism, Inborn Errors / Q000378:metabolism*; D002675:Child, Preschool; D003241:Consanguinity; D004393:Dwarfism, Pituitary / Q000378:metabolism*; D013006:Growth Hormone / Q000378:metabolism*; D006801:Humans; D007328:Insulin / Q000097:blood; D008297:Male; D013002:Somatomedins / Q000097:blood* / Q000172:deficiency; D013577:Syndrome
D007328:Insulin; D013002:Somatomedins; D013006:Growth Hormone