This study was carried out in order to determine whether children with a transitory type of growth hormone deficiency showed an accelerated growth in height velocity on treatment with human growth hormone (HGH).
Following careful diagnostic routine procedures 13 extremely short children were diagnosed as having isolated growth hormone deficiency, and were successfully treated with HGH. A true isolated growth hormone deficiency was present in 5 of the children, whereas 8 showed a normal increase in serum growth hormone on repeated growth hormone stimulation tests after their development of puberty and termination of HGH treatment. Three boys with bone ages of 5.5, 8.0 and 9.5 years showed an undisputable effect following HGH administration. They showed an initial growth at the start of treatment, and a second growth spurt during development of puberty. Two of the boys reached final statures of 14 cm taller than the predicted heights. The other patients, including the children with true isolated growth hormone deficiency showed an initial spurt of growth at the start of the HGH treatment immediately followed by a pubertal growth spurt. The mean acceleration of height velocity for the children with true isolated growth hormone deficiency was from 3.4 cm during the year before treatment to 7.0 cm during the first year on treatment, as compared to 2.8 and 7.4 cm, respectively, for the children with transitory growth hormone deficiency. A girl with severe anorexia nervosa who had a transitory growth hormone deficiency, showed an accelerated high velocity from 1.1 cm to 7.6 cm during the first year following treatment with HGH.
The question whether HGH treatment should be made available to all short children with no known syndrome, and presenting a height less than −3.5 sds, a bone age/chronological age ratio of less than ⅔, and a height velocity less than −2 sds is discussed. The only way to know if a child will respond to HGH treatment is to give it for a trial period of at least six months. At least a physiological stimulus to growth hormone secretion should be decisive in the selection of growth retarded children for HGH treatment. Different mechanisms seem to be responsible for physiological growth hormone secretion to sleep or exercise, and the secretion obtained with pharmacological stimuli.