Dwarfism, hypopituitarism, and growth hormone.

Small stature or growth retardation is a frequent problem in children, often leading to serious psychological repercussions. In some patients, as for instance in those with achondroplasia, severe hypothyroidism, or classical Turner's syndrome, the underlying disorder can easily be recognized. More often the growth retarded child presents no other symptoms, and the cause of dwarfism remains obscure in spite of a good history and a careful physical examination. A few years ago, many of these children were treated with anabolic steroids without further investigation. Most of them respond to anabolic steroids with an impressive spurt of growth, but bone maturation is likely to be more accelerated than growth, resulting in a decrease rather than the intended increase in the final height attained. Now hope has turned from the anabolic steroids to growth hormone (GH) which in contrast to anabolic steroids stimulates growth rather than bone maturation. GH shows a remarkable species specificity in chemical structure and biological activity. In man only human GH (HGH) is effective. The structure of HGH has recently been elucidated (Li, Liu, and Dixon, 1966). It is a polypeptide chain with a molecular weight of 21,500 consisting of 188 amino acids of known sequence. The synthesis of such a large molecule is not yet possible, but it may soon be possible to synthesize a smaller, biologically active part ofthe original molecule, as has been successfully done with ACTH. At the moment we still depend on HGH extracted from pituitary glands obtained at necropsy. The supply of this material is scarce, and experience with its therapeutic use still limited. So far it seems that dwarfs with supposed deficiency of GH respond with a marked growth acceleration, whereas dwarfs without GH deficiency show only a small or dubious response (Soyka, Ziskind, and Crawford, 1964; Mason and Tanner, 1967). It is, therefore, important to reserve the available HGH for treatment of children with hypopituitarism, and to refuse it to children with dwarfism of other origin. This raises the question of how to diagnose GH deficiency in children, and this difficult problem is discussed in this issue of the Archives by several Most workers in this discipline agree that on clinical grounds alone the diagnosis of GH deficiency can only be suspected, and that the impressive battery of available diagnostic tests solves many but not all diagnostic problems. Some of the tests are, as Hubble points out, time consuming and …