Growth hormone treatment and the short child: to treat or not to treat?

Growth hormone neurosecretory dysfunction associated with ring chromosome 18

The patient was a girl 5 years and 1 month old of markedly short stature (-3.9 SD) for her chronological age. Although her karyotype was 46, XX, r(18)(p11q23), there were no symptoms of a chromosomal deletion. Other authors have described cases with a ring autosome showing a phenotype with short stature alone as 'ring syndrome', regardless of which autosome is involved. The present case seems to fall into this category. Although blood growth hormone (GH) showed normal responses to four types of provocative tests, the mean value of blood GH levels obtained at 30 min intervals for 24 h was low, indicating the existence of growth hormone neurosecretory dysfunction (GHND).

Clinical diagnoses of children with extremely short stature and their response to growth hormone

This study was undertaken to determine the prevalence of clinical diagnoses in a group of children with extremely short stature (standard deviation score for height, < -2.5) and to determine whether the classification might help in predicting response to human growth hormone (hGH) treatment. We classified 49 children referred consecutively to our outpatient clinic for evaluation of short stature with heights < -2.5 standard deviation score and bone ages < 9 years for girls or < 10 years for boys (to avoid an effect of puberty on the response to hGH). The diagnostic categories were growth hormone (GH) deficiency, constitutional delay, familial short stature, and primordial short stature. After referral, Turner syndrome was diagnosed in two children. The remaining 47 children were classified according to primary criteria, considered essential for the diagnosis, and secondary criteria, considered necessary but of lesser importance. There were five children, four children, no children, and one child classified, respectively, with GH deficiency, constitutional delay, familial short stature, and primordial short stature by using the most rigorous definitions of the diagnoses. There was significant overlap in the diagnoses other than GH deficiency. Growth hormone deficiency defined by the primary criterion of peak stimulated GH values < 5 micrograms/L was the most definitive. Of the 47 children, 7 were classified as GH deficient by this criterion and 5 were classified as GH deficient by the primary and secondary criteria. The mean pretreatment growth rate (3.1 +/- 1.9 cm/yr) of the group with stimulated GH values < 5 micrograms/L was significantly less than that in the other groups (4.2 +/- 1.5 cm/yr). The mean growth rate of the children with GH deficiency during treatment with hGH was greater than that in the other groups and was 3.4 times greater than the pretreatment growth rate. The mean growth rate of children in the other groups during hGH treatment was twofold greater than the pretreatment growth rate. We conclude that except for GH deficiency, children with an extreme degree of short stature are not easily classified by standard diagnostic criteria, and that most short children have a positive response to hGH therapy regardless of the diagnosis; therefore a specific clinical diagnosis should not be used to exclude children from hGH therapy.

Effects of growth hormone administration in pediatric renal allograft recipients

The efficacy of recombinant human growth hormone (rGH) was assessed in five pediatric allograft recipients with severe growth retardation despite successful renal transplants. rGH 0.05 mg/kg per dose was given six times weekly by subcutaneous injection to five prepubertal children (mean age 15.2 +/- 2.0 years) all of whom had bone ages less than or equal to 12 years (10.0 +/- 1.4 years), a height standard deviation score of less than -2.5 (-4.9 +/- 1.5), no evidence of catch-up growth, a calculated glomerular filtration rate (GFR) of more than 40 ml/min per 1.73 m2 (51 +/- 6.8 ml/min per 1.73 m2), and stable renal function on alternate-day prednisone (16.7 +/- 2.6 mg/m2 per dose). Growth hormone profiles were abnormal in all children before treatment. rGH administration led to a significant increase in both growth rate (3.5 +/- 1.6 cm/year pre therapy, 8.5 +/- 1.4 cm/year post therapy, P less than 0.001) and percentage of expected growth velocity for bone age (67 +/- 31% pre therapy, 163 +/- 27% post therapy, P less than 0.001) with evidence of true catch-up growth. During the study period, three children had the appearance of secondary sexual characteristics, and one had premature advancement of his bone age. GFR decreased in three children, and in one rGH was discontinued due to a steady rise in serum creatinine. No significant changes were seen in serum calcium, phosphorus, cholesterol, triglycerides, glucose, or thyroid function, although a significant increase in alkaline phosphatase was found. In summary, growth-retarded pediatric renal allograft recipients may have abnormal endogenous GH production and respond favorably to rGH.(ABSTRACT TRUNCATED AT 250 WORDS)

Case report: Crouzon syndrome with short stature

A five-year-old boy with Crouzon Syndrome, short stature, and delayed bone age was found to have partial growth hormone deficiency. Accelerated growth was observed after human growth hormone replacement. Children with Crouzon Syndrome should be followed closely for all growth parameters, not just head circumference.

Intranasal activity of the growth hormone releasing peptide His-D-Trp-Ala-Trp-D-Phe-Lys-NH2 in conscious dogs

This series of experiments was conducted to evaluate the growth hormone (GH) releasing activity of intranasally administered His-D-Trp-Ala-Trp-D-Phe-Lys-NH2 (GHRP-6, SK&F 110679) in conscious dogs. Intranasal administration of GHRP-6 increased plasma growth hormone levels in the conscious dog in a dose-related manner. Doses of 0.25 and 0.5 mg/kg produced GH levels of 11.3 +/- 4.8 ng/ml and 28.6 +/- 8.0 ng/ml, respectively. Peak levels were observed 15 minutes after dosing and GH levels were elevated for up to 105 minutes after intranasal dosing. Intranasal administration of isotonic saline did not produce any change in basal (negligable) GH levels. When GHRP-6 was given by the intravenous route, a maximal dose of 0.5 mg/kg, produced a peak plasma GH concentration of 60.8 +/- 10.5 ng/ml. Saline had no effect on GH levels when given intravenously. Using the intravenous and intranasal GH response data (i.e., area under the time-response curves), the intranasal bioavailability of GHRP-6 was estimated to be 34.4 to 44.9%. The results of these studies suggest that significant activity and excellent bioavailability can be achieved when GHRP-6 is administered by the intranasal route to conscious dogs. Based on these results, the intranasal activity of GHRP-6 should be evaluated in man. The successful intranasal administration of this peptide in man should provide GH therapy with reduced patient discomfort and better patient compliance when compared to presently available parenterally administered remedies.

Growth hormone for short stature not due to classic growth hormone deficiency

The advent of recombinant DNA technology has resulted in potentially unlimited supplies of growth hormone. Sufficient quantities are now available not only for the long-term, uninterrupted treatment of GH-deficient children but potentially for the treatment of non-GH-deficient patients with other short stature or growth attenuating disorders. Short-term studies have demonstrated an improvement in the growth rates of subjects with isolated short stature, Turner syndrome, and chronic renal failure; and additional studies are under way to assess the efficacy of GH therapy of other short stature syndromes. However, the long-term efficacy and possible adverse effects of GH treatment in these situations is not known. Until there has been more experience, GH deficiency should remain the primary indication for GH treatment. Growth hormone should not be considered routine therapy for other conditions associated with or resulting in short stature. However, research should continue in these areas to define which children may benefit from GH treatment.

A controlled trial of methionyl growth hormone therapy in prepubertal children with short stature, subnormal growth rate and normal growth hormone response to secretagogues. Dutch Growth Hormone Working Group

Thirty short and slowly growing children with normal plasma growth hormone (GH) responses to standard provocation tests were randomly assigned to either a group (n = 20) undergoing treatment with methionyl GH (somatrem), 2 IU per m2 body surface s.c. daily, or a control group (n = 10). Twelve out of 18 children who completed the first year of treatment showed a height velocity increment of more than 2 cm/year. The mean (SD) growth velocity of the treatment group increased by 3.0 (1.9) cm/year over the first year, compared with -0.2 (0.7) cm/year in the control group. Neither parameters of endogenous GH secretion nor plasma IGF-I levels showed a significant correlation with the growth response. Of the auxological variables studied, pre-treatment growth velocity (r = -0.8) and the short-term height velocity increment (r = 0.7-0.9) showed significant correlations with the growth response in the first year of treatment. Somatrem therapy was without side effects, except in one child who developed anti-GH antibodies in combination with a poor growth response.