Growth hormone increases rate of pubertal maturation

Recombinant human growth hormone for children with renal failure

The pathogenesis of growth retardation in children with chronic renal failure (CRF) is clearly multifactorial. A major breakthrough in the understanding of the pathogenesis of uremic growth failure was achieved only recently by a more detailed analysis of the growth hormone (GH)/insulinlike growth factor (IGF) axis. Uremia is characterized by an insensitivity to the somatotropic action of GH. The mechanisms that account for this insensitivity include reduced hepatic GH receptor expression, decreased production of IGF-I, and inhibition of IGF bioactivity by increased binding of IGFs to their specific binding proteins. Recombinant human growth hormone (rhGH) in supraphysiological doses is able to overcome the partial GH resistance and to stimulate longitudinal growth under both experimental and clinical conditions. One possible mechanism of action of rhGH in uremia is the restoration of circulating IGF bioactivity, which results from the differential regulatory effect of rhGH on circulating IGF-I and IGFBP-3 concentrations. RhGH has proven to be an effective, safe, and well-tolerated new treatment modality for growth-retarded children at all stages of CRF. There is strong evidence that final height will increase in these children. Other than a modest chronic stimulation of insulin secretion, no frequent side effects have been observed; in particular, no acceleration in loss of residual renal function has been seen in children treated before the onset of end-stage renal failure. In children after transplantation, rhGH is also effective, but the potential risk of interference with graft function is not yet sufficiently defined.

The safety and effectiveness of human growth hormone using pharmacological dosing

Human growth hormone in currently recommended dosage is effective in many short children, irrespective of their endogenous growth-hormone status. This suggests that present dosing is pharmacological rather than physiological. As for any drug, issues of safety should be of paramount concern. Reassuring short-term data with pharmacological dosing or long-term data with replacement dosing cannot guarantee the ultimate safety of this form of therapy. The risk of future malignancy should be of particular concern. Poorly growing children without classic (severe) growth-hormone deficiency constitute an increasing proportion of children treated with human growth hormone. There are no satisfactory criteria for the diagnosis of neurosecretory growth-hormone dysfunction. The closer to puberty these children are treated, the less likely it is that there will be benefits in terms of increased final height. Recommendations as to a 'safety first' approach to growth-hormone treatment are given. A multicentre controlled trial is urgently needed to establish the benefits of treating children with neurosecretory growth hormone dysfunction.

Effect of chemotherapy on growth

Growth restriction has been demonstrated clearly following the treatment of childhood malignancies, even in the absence of irradiation to the hypothalamic-pituitary axis. The use of CT and spinal irradiation in the original treatment of brain tumours has a marked effect on growth. This effect is most profound in children who have received both treatments and cannot be overcome using GH therapy at conventional doses.

Growth and puberty after growth hormone treatment after irradiation for brain tumours

The impact of treatment with either cranial or craniospinal irradiation with or without cytotoxic chemotherapy for a brain tumour distant from the hypothalamic-pituitary axis was assessed in 29 children who had reached final height. All had received growth hormone treatment for radiation induced growth hormone deficiency. Final height, segmental growth during puberty, and duration of puberty were studied. Both craniospinal irradiation and the use of chemotherapy resulted in a significant and equal reduction in final height; this effect in those children who received both craniospinal irradiation and chemotherapy was additive. The degree of height loss was related to the age at irradiation, the most profound effect on final height occurring in the youngest at irradiation. The mean duration of puberty from G2-G4/B2-B4 (1.97 years) was not significantly different from the duration of puberty in normal children. Growth hormone increases growth velocity in children with radiation induced growth hormone deficiency but their final height is significantly less than their mid-parental height. The use of spinal irradiation and chemotherapy in the original treatment of brain tumours has a marked effect on growth which is not overcome with the use of growth hormone treatment in current doses. Early puberty of normal duration contributes to poor growth.

Somatotropin and somatostatin effects on vitamin K-dependent plasma coagulation factors

The effects of somatotropin (0.2 mg/kg body mass) and somatostatin (0.1 mg/kg body mass) on plasma coagulation factors II, VII, IX, X and some general indexes of hemocoagulation were examined. Hormones were injected subcutaneously in male Wistar rats on 3 consecutive days. Boehringer Mannheim tests and Schnitger and Gross coagulometer were used for clotting factor determination. Somatotropin caused significantly decreased activity of factors II, VII and X (P < 0.001) and IX (P < 0.05). Somatostatin alone, as well as somatotropin after somatostatin pretreatment considerably increased the activity of factors II, VII and X (P < 0.001), while factor IX was non-significantly suppressed. It is concluded that somatotropin and somatostatin are possible regulators of biosynthesis of vitamin K-dependent plasma coagulation factors. Somatotropin depresses the activity of factors II, VII, IX and X and causes hypocoagulability, while somatostatin not only prevents the inhibiting effect on factors II, VII and X, but also increases their activity and causes hypercoagulability.

Long-term results of growth hormone therapy in children with short stature, subnormal growth rate and normal growth hormone response to secretagogues. Dutch Growth Hormone Working Group

BACKGROUND AND OBJECTIVE

Growth hormone treatment in children with idiopathic short stature (ISS) leads to growth acceleration in the first years, but the effect on final height is still poorly documented. We therefore studied the long-term effect of GH therapy in children with idiopathic short stature.

DESIGN

We have treated 27 prepubertal children with ISS with recombinant human GH (rhGH) in an initial dosage of 2 IU/m2 body surface/day subcutaneously, which was doubled either after the first year if the height velocity increment was less than 2 cm/year, or thereafter if height velocity fell below the P50 for bone age. Growth and bone maturation of the treatment group (ISS group, n = 21) were compared to those of an untreated control group with ISS (ISS controls, n = 27) and of a group of rhGH treated children with isolated GH deficiency (GHD group, n = 7).

RESULTS

In 9 patients of the ISS group still on treatment, height standard deviation score (HSDS) for chronological age increased from -3.8 +/- 0.7 to -2.3 +/- 0.9 (mean +/- standard deviation) over 6 years, while in matched ISS controls HSDS for age did not change. HSDS for age in the GHD group increased from -3.9 +/- 0.6 to -1.8 +/- 0.7 after 4 years, significantly more than the ISS group. Bone maturation was accelerated in the ISS and GHD groups. HSDS for bone age and predicted adult height did not change in either group. Final height in 12 children of the ISS group was -2.6 +/- 1.0 SDS. In the untreated controls final height was similar. A low integrated GH concentration over 24 hours, a low GH peak to provocative stimuli, and minimal initial BA delay predicted a favourable outcome.

CONCLUSION

rhGH treatment in this group of children with idiopathic short stature did not increase average final height. Part of the heterogeneity of the response can be attributed to the variation in endogenous GH secretion and initial bone age delay.

Combination treatment with growth hormone and gonadotropin-releasing hormone analogs in short normal girls

To improve final adult height, we treated with growth hormone (0.65 +/- 0.07 (mean +/- SD) IU.kg-1.wk-1) and gonadotropin-releasing hormone analogs (66 +/- 9 micrograms.kg-1 every 28 days) a group of seven short normal girls in early puberty with a chronologic age (CA) of 11.50 +/- 0.95 years, predicted adult height (PAH) lower (0.003 < p < 0.001) than mean target height, and without any endocrine abnormalities. The results were compared with those obtained in a similar group of seven untreated girls considered as control subjects. The mean period of combined therapy was 2.01 +/- 0.52 years; in two subjects treatment is still in progress. The value of height standard deviation score for bone age (BA) improved from -1.69 +/- 0.47 to -1.04 +/- 0.56 (p = 0.001); height age (HA)/BA ratio also increased from 0.83 +/- 0.05 to 0.90 +/- 0.04 (p < 0.01), as did PAH (from 146.8 +/- 4.4 to 152.9 +/- 3.6 cm; p < 0.002). The ratio of gain in HA to gain in BA was 2.08 +/- 0.78. Pubertal stages showed an arrest in five cases and a regression in the other two girls. After administration of gonadotropin-releasing hormone analogs was interrupted, in four of five girls growth hormone was administered alone for a further period of 6 to 18 months to improve their physiologic growth spurt. The present height in five girls is higher than PAH before therapy. In the treated girls the height values for BA, for BA/CA and HA/BA ratios, and for PAH were higher (0.002 < p < 0.04) than those in control subjects. This preliminary study demonstrates that combination therapy with growth hormone and gonadotropin-releasing hormone analogs in short, endocrinologically normal girls may be useful in improving both height prognosis and predicted adult height. Further studies are necessary to reach definitive conclusions regarding the efficacy of this kind of therapy.

Effect of growth hormone therapy on final versus predicted height in short twelve- to sixteen-year-old boys without growth hormone deficiency

The effect of growth hormone therapy on final height in 28 short boys without growth hormone deficiency was evaluated retrospectively. The boys had received growth hormone for at least 2 years and were close to final height when therapy was stopped. The mean estimated final height was very close to that predicted from the pretherapy bone age. The fact that bone age advanced a mean of 4.9 years during a mean of 3.5 years of therapy may account for the lack of effect on final height.

The timing of sexual maturation in a group of US white youths

The purpose of this study was to present US reference data for chronological ages at which stages of sexual maturation were observed in white youths. Recent serial data from 78 males and 67 females were analyzed to obtain descriptive statistics for the ages at onset of these stages and the mean ages at which the stages are observed. These reference data should assist the identification of white US youths who are maturing at rapid or slow rates and the interpretation of growth data.

The effect of recombinant IGF-I on anterior pituitary function in healthy volunteers

OBJECTIVE

Insulin-like growth factor-I is the mediator of many of the actions of GH and is a potent metabolic regulator. Recombinant IGF-I (rhIGF-I) is of potential value in the treatment of syndromes associated with either GH or insulin resistance. This study was designed to assess the effects of subcutaneous (s.c.) rhIGF-I on anterior pituitary function.

DESIGN

Double-blind, placebo controlled, randomized cross-over study. The interval between investigations was 2 weeks.

SUBJECTS

Twelve normal volunteers received on one occasion a single s.c. dose of 40 micrograms/kg rhIGF-I and on the other, placebo.

MEASUREMENTS

Circulating levels were measured, over 24 hours, of GH, LH, FSH, PRL, TSH, cortisol, ACTH, glucose, IGF-I, IGF-II, insulin, C-peptides; IGF binding proteins by Western ligand blotting; total IGF bioactivity using FRTL-5 thyroid cells; and glucose by the glucose oxidase method.

RESULTS

Recombinant IGF-I increased AUC for plasma IGF-I, measured by radioimmunoassay (rhIGF-I mean 7065 +/- SEM 33 vs 3895 +/- 204 micrograms/l, P < 0.0001) and IGF bioactivity (22.5 +/- 3.4 vs 14.2 +/- 1.8 U/ml, P < 0.001) but plasma IGF-II fell (9308 +/- 403 vs 11052 +/- 451 micrograms/l, P < 0.0001). There was no biochemical or clinical evidence of hypoglycaemia and no difference in mean glucose levels. No difference existed in AUC for GH, LH, FSH, ACTH and cortisol between rhIGF-I and placebo; additionally, pulse number and amplitude for GH and LH were unaffected. TSH fell following rhIGF-I (33.0 +/- 3.36 vs 42.5 +/- 5.98 mU h/l, P = 0.01). Both mean plasma C-peptide (0.73 +/- 0.06 vs 0.91 +/- 0.05 nmol/l, P = 0.03), and insulin (10.81 +/- 1.02 vs 15.36 +/- 1.18 mU/l, P = 0.03) were lower following rhIGF-I. There was no change in IGFBPs.

CONCLUSION

A single injection of 40 micrograms/kg of subcutaneous rhIGF-I does not cause hypoglycaemia. IGF bioactivity was increased without inhibition of GH secretion. The only change observed in anterior pituitary function was a fall in plasma TSH.

Age as a determinant of the impact of growth hormone therapy on predicted adult height

OBJECTIVE

Final adult height is determined by both childhood and pubertal growth. The later is a function of growth velocity and bone maturation, and both are regulated by growth hormone. In a study of the safety and efficacy of GH therapy, we analysed the impact of age on bone maturation and predicted adult height.

PATIENTS AND METHODS

The subjects were 65 male patients with GH deficiency, as diagnosed by pharmacological or physiological tests, who participated in a multicentre trial and completed 3 years of hGH therapy. The age range at initiation of therapy was 3.1-15.7 years. Subcutaneous injections of hGH were given in a dose of 0.3 mg/kg/week, in thrice-weekly doses. Calculation of the adult height prediction was performed on annual growth parameters using the Bailey-Pinneau, TW-II and Roche methods.

RESULTS

The rate of pubertal advancement correlated positively with the child's age at initiation of therapy. The bone age advanced in positive correlation with chronological age, and by the end of 3 years of hGH therapy the delta-bone age/delta-chronological age ratio increased to 1.5 for children with an age at start of therapy of 10.7 years. During the adolescent years, the predicted gained height over 3 years of therapy declined, in correlation with age, and became negative at a therapy-initiation age of 12.9 years.

CONCLUSIONS

In a retrospective analysis of a group of children with heterogeneous GH secretory ability, GH induced acceleration of growth, around the age of normal puberty, advanced the age of pubertal onset and accelerated pubertal progression which, in turn, expedited bone maturation and thereby restricted predicted adult height gain from hGH therapy.

Growth and metabolic consequences of growth hormone treatment in prepubertal short normal children

Growth and the metabolic effects of growth hormone were monitored in a randomised, controlled group of 41 short, normal, prepubertal children. The treated group received daily injections of growth hormone as Genotropin (Kabi Pharmacia) 30 IU/m2/week. Fifteen children in the treated group (21 children) have completed three years of treatment, have grown significantly more than 14 (of 20) untreated children, and have a significantly greater adult height prediction. They do, however, remain leaner (body fat 13.5% in the treated group, 18% in the untreated group) and relatively hyperinsulinaemic (insulin 66.7 pmol/l in the treated group, 44.5 in the untreated group) after three years compared with untreated children. Although growth hormone appears to improve the height potential of prepubertal short normal children, the long term outcome is still uncertain.

Does early physical maturity influence breast cancer risk?

Earlier onset of menarche and tallness in adult women are mainly confirmed as risk markers for breast cancer. Recent disparate case-control studies have reported abdominal-type obesity and higher circulating levels of insulin, testosterone and insulin-like growth factor 1, to be further risk markers for breast cancer. There is evidence that abdominal-type obesity is recognisable in girls even before puberty, and disparate studies have shown it to be correlated with earlier onset of menarche, insulin resistance leading to hyperinsulinaemia, and an abnormal sex steroid profile. The implications are that earlier onset of puberty in a subset of girls can lead to more prolonged exposure of developing breast tissue to an abnormal sex steroid profile and also to a higher circulating level of insulin. It is postulated that these metabolic/endocrine concomitants of abdominal-type obesity could play a role in promoting mammary carcinogenesis at a young age, particularly if genetic predisposition is present.

Combined treatment with growth hormone and luteinizing hormone releasing hormone-analogue (LHRHa) of pubertal children with familial short stature

We evaluated the 12 month growth of 18 pubertal children with familial short stature randomly assigned to clinical follow-up (group A), GH treatment alone (group B) and GH+LHRH analogue (LHRHa) treatment (group C). Height velocity increased significantly compared to baseline in groups A and B (4.7 +/- 0.4 vs 6.6 +/- 0.6 and 4.4 +/- 0.3 vs 8 +/- 1 respectively), but not in C (5 +/- 0.5 vs 6.5 +/- 0.4). Moreover in group B height and height prognosis standard deviation score SDS) also were higher (-2.2 +/- 0.2 vs -1.7 +/- 0.2 and 1.8 +/- 0.3 vs -1 +/- 0.2, respectively). Comparisons among the groups showed a significant increase in group B vs the other groups of height velocity SDS (3.9 +/- 1.3 vs 0.4 + 1 and 0.3 +/- 0.7) and of height prognosis SDS (-1 +/- 0.2 vs -2.4 +/- 0.3 and -2.4 +/- 0.3). In conclusion, after one-year treatment, GH seems to be more effective in stimulating growth than GH +/- LHRHa, even if studies of longer duration and/or follow-up are needed.

Long-term treatment with growth hormone in Noonan's syndrome

Five children (four boys, one girl) with Noonan's syndrome were treated with growth hormone for a mean of 2.9 (range 1.8 to 4.6) years. Treatment was commenced at a mean age of 3.9 (range 2.5 to 6.0) years. After one year of treatment, height velocity SDS increased from a mean of -2.1 (range -4.1 to -0.3) to a mean of +3.1 (range +2.0 to +3.5). Subsequently, height SDS increased significantly from -3.3 (range -4.2 to -2.2) to -2.4 (range -3.3 to -1.6). Although in all patients a marked decrease in height velocity was observed in the following years of treatment, compared to the first year, height SDS continued to improve in comparison to pretreatment (mean height SDS in the third year for four patients was -2.1) (range -3.1 to -1.4). In the four patients who had completed their second year of treatment, height SDS for bone age had increased from -1.8 (range -2.8 to -0.9) to -1.2 (range -1.6 to -0.6).

Growth hormone-receptor messenger RNA in the rat ovary: regulation and localization

The results of several reports indicate that GH can modulate ovarian function. In the present study, the expression of the growth hormone-receptor (GH-R) mRNA was studied in the rat ovary using an RNA probe corresponding to a part of the extracellular domain of the GH-R. The probe hybridized to two major transcripts with estimated sizes of 4.0 kb and 1.2 kb in RNA extracted from liver and ovary. Recently, these transcripts have been shown to encode the GH-R and the GH-binding protein (GH-BP). The ontogeny of the GH-R/GH-BP mRNA expression was studied using Northern blot analysis and a solution hybridization RNase protection assay. In the liver GH-R/GH-BP mRNA levels increased with age, while in the ovary, the levels decreased between 1 and 5 weeks of age. Hypophysectomy caused a decrease in GH-R/GH-BP gene expression in the ovary, an effect which could be partly reversed with a single injection of GH (2 mg/kg). No significant changes in the ovarian concentration of GH-R/GH-BP transcripts were seen during the estrus cycle. Using in situ hybridization GH-R/GH-BP transcripts were found to be most abundant in follicles. Northern blot analysis of RNA extracted from isolated granulosa cells and corpora lutea showed that both these compartments contained GH-R and GH-BP mRNA, although more abundant in granulosa cells. Immunoreactive GH-R was detected in granulosa cells of healthy follicles, corpus luteum, and in the germinal epithelium.(ABSTRACT TRUNCATED AT 250 WORDS)

New challenges in the growth field

When unlimited supplies of biosynthetic human growth hormone (hGH) became available in the late 1980s, the envisaged potential of its therapeutic applications was enormous in that it was hoped that perhaps most short children would be able to be made taller. However, this seems to have been far too simplistic a view and certainly in those children with various growth disorders treated with pharmacological doses of growth hormone (GH), the potential for increased final height does not appear to be fulfilled, with the exception of girls with Turner's syndrome. Further challenges in the growth field involve the manipulation of pubertal development during concomitant GH therapy.

Short stature: new challenges in growth hormone therapy

Until recently, the limited supplies of pituitary derived growth hormone (GH) enabled us to treat only those patients who were classical GH deficient. With the unlimited supplies of recombinant GH available, there is no limitation to the number of patients we can treat. It becomes necessary, however, to select those patients who will most benefit from GH therapy. Our preliminary results demonstrate that the short-term growth response to growth hormone is not an all-or-none phenomenon. The lower the growth velocity and the growth hormone reserve, the better the growth response to therapy. On the other hand we do not recommend institution of GH therapy for children with a normal growth rate and a normal GH spontaneous secretion. In children with classical GH deficiency (GHD) and in children with a subnormal spontaneous secretion of GH (NSD) adult height prediction decreases when GH therapy is started at an age older than 12. We have found that GHD and NSD boys differ in their growth pattern. Pubertal maturation and bone age maturation progress more rapidly in NSD patients. Therefore special caution is needed in NSD patients older than 12 years. The older the patient and the longer the treatment period, the faster the pubertal process can advance. Further studies are needed before recommendations for therapy in non-classical GHD patients can be made. Until patients involved in clinical trials reach final height, recommendations for new indications cannot be made.

Effects of growth hormone therapy on the developmental changes of follicle stimulating hormone and insulin-like growth factor-I serum concentrations in Turner's syndrome

OBJECTIVE

The aim was to investigate whether, in the absence of gonads, GH could bring forward the age of neuroendocrine activation resulting in onset of puberty.

DESIGN

In girls with Turner's syndrome, we evaluated the effects of GH therapy on developmental changes in FSH serum concentrations used as an indicator of neuroendocrine maturation in the absence of gonads.

PATIENTS

Thirty-nine girls with Turner's syndrome aged 4.0-17.1 years were treated using GH (25 IU/m2 week) for 1 year.

MEASUREMENTS

Serum levels of FSH and IGF-I were measured before initiation of GH therapy and 12 months later, after interruption of GH treatment for 2 days.

RESULTS

Pretreatment FSH levels were low between 6 and 10 years and increased markedly at 10-11 years of age. This pattern was unchanged after 1 year of GH therapy. Pretreatment IGF-I levels were positively correlated with age and they were uniformly increased after 1 year of GH therapy.

CONCLUSIONS

Our data suggest that GH and its effector, IGF-I, do not influence the timing of the onset of puberty through an effect on its neuroendocrine control.

Efficacy and safety of growth hormone treatment in short children with renal allografts: three year experience. Members of the German Study Group for Growth Hormone Treatment in Children with Renal Allografts

The majority of children with renal allografts have diminished growth and reduced final height. Impaired allograft function and glucocorticoid treatment are the main contributing factors. Since recombinant human growth hormone (rhGH) treatment was able to counteract the growth depressing effects of glucocorticoids in experimental uremia, an open-labeled prospective study in 17 short children with renal allografts was designed to investigate the efficacy of rhGH therapy (30 IU/m2/week) with special emphasis on the safety regarding graft function and carbohydrate metabolism. Height velocity in prepubertal children (N = 10) increased from baseline median 2.2 cm/year to 7.9 cm/year after one year (P < 0.01), 7.2 cm/year after two years (P < 0.01), and 5.5 cm/year (P < 0.05) after three years of rhGH therapy. This resulted in a normalization of height in three out of seven patients after two years and in three out of five after three years of therapy. Growth stimulation in pubertal children was less consistent. Bone maturation paralleled chronological age. The effect of rhGH treatment on longitudinal growth may be partially attributable to the improved ratio between the serum concentration of the insulin-like growth factor (IGF)-I and its major binding protein (BP) IGFBP-3 leading to a normal IGF bioactivity. The incidence of acute rejection crises in the study group (corrected for time after grafting) did not differ from that of untreated retrospective "controls" (0.10 vs. 0.12 episodes per patient and year). No systematic effect of rhGH on glomerular filtration rate assessed by repeated inulin and creatinine clearances was noted.(ABSTRACT TRUNCATED AT 250 WORDS)

Conventional and nonconventional uses of growth hormone

Although GH has been available as a therapeutic agent for the GH-deficient child for more than 30 years, the conditions of its use have yet to be optimized. The availability of biosynthetic material has provided researchers with the opportunity to develop the protocols necessary to begin to finally answer the most fundamental questions pertaining to dose, frequency, and duration of treatment. It has also permitted the initiation of prospective trials in a large number of conditions that result in childhood short stature, with the expectation that some or many of them will be treated effectively and safely. Finally, it has opened the door to an entire spectrum of potentially new uses of GH and other growth factors for so-called nonconventional indications. That these have implications that range from the short-term rapid healing of a burn graft site, to the more efficient induction of ovulation, to the long-term preservation of lean body mass has excited the interest of investigators in many fields of medicine and physiology. Thus, the recent progress reported in this paper is really the beginning of the new research that will take place with GH and growth factors.

The potential relevance of growth hormone to female reproductive physiology and pathophysiology

OBJECTIVE

To assess possible interfacing between the somatotrophic and reproductive axes.

DESIGN

Literature review.

MAIN OUTCOME MEASURES

Ovarian growth hormone reception and action.

RESULTS

The available literature strongly supports a permissive role for the somatotrophic axis in the reproductive process.

CONCLUSIONS

Although a role for growth hormone in reproductive biology appears highly likely, its relevance to the process of puberty and to the normal workings of the menstrual cycle, as well as its possible application in reproductive pathology must await further investigation.

Growth hormone deficiency throughout puberty

Growth during puberty does not appear to be the major determinate of final height in isolated GH deficient patients. Early diagnosis and commencement of therapy are probably the most important factors, as reflected by the correlation between final height and height at the onset of puberty. The cost effectiveness of increasing the dose of GH during puberty does not appear to represent any advantage from the data presently available. Indeed, such an approach may have a deleterious effect on final height by shortening the duration of pubertal maturation. Further prospective studies are required to demonstrate the effectiveness of manipulating the onset and duration of puberty using gonadotrophin releasing hormone analogues on final height in isolated GH deficiency.

Septo-optic dysplasia and growth hormone deficiency: accelerated pubertal maturation during GH therapy

We report four patients (three male, one female) with septo-optic dysplasia and growth hormone deficiency. All had GH therapy for a period of four to eight years until reaching final height. In all four cases bone maturation during puberty was accelerated (1.4 to 1.9 "years"/year), resulting in a final height which was clearly below the predicted height. The progress of pubertal stages was very short in all patients. In three patients TSH and prolactin release after TRH stimulation were increased. These data support a hypothalamic original of the endocrine disorder. Insufficient GH release, even after repeated GHRH stimulation, is in contrast to this assumption. In one case there was a late manifestation of neurohormonal diabetes insipidus, which indicates the possibility of later disease progression. MR imaging of the brain demonstrated variable malformation of the septum pellucidum, chiasma and nervus opticus or the pituitary gland, respectively.

The role of treatment with growth hormone in infertile patients

The reality of the interaction of GH and its mediator, IGF-I, with gonadotrophins is now established. The results of these studies and others have obvious implications, both physiologically and clinically. Co-treatment with GH augments the gonadal response to gonadotrophins, and it seems to be of particular value in patients who are poor responders to gonadotrophin treatment and who have pituitary hypofunction induced surgically, idiopathically (hypogonadotrophic hypogonadism) or medically (treatment with GnRH analogues). There is conflicting evidence as to whether the observed effect of GH is exerted directly on the ovary or mediated through IGF-I. Treatment with GH causes a distinct increase in serum IGF-I concentrations, which correlate with, but are always higher than, follicular fluid levels, suggesting that GH stimulates hepatic production of IGF-I and that the effect on the ovary is endocrine. Further research will, hopefully, clearly define the precise therapeutic role of GH in the induction of ovulation, the selection of the most appropriate group of patients to be treated, and the minimum dose of GH needed to sensitize the ovary. Further studies are also needed to explore the action of GH and to define the role of IGF-I in the process of follicular development.

Puberty in children with idiopathic growth hormone deficiency on growth hormone treatment: preliminary analysis of the data from the Kabi Pharmacia International Growth Study

In total, 524 children (335 boys, 189 girls) with idiopathic growth hormone deficiency (GHD) who had entered puberty after at least 1 year of growth hormone (GH) treatment were studied. Spontaneous onset of puberty occurred in 319 boys and 174 girls, and puberty was induced in 16 boys and 15 girls. Median chronological and bone ages at onset of spontaneous puberty were 14.8 and 13.4 years in boys, and 13.3 and 11.8 years in girls, respectively. Age at onset of spontaneous puberty was correlated to age at start of GH treatment. Puberty was induced at a median chronological age of 16.0 years in boys and 14.4 years in girls. Height velocity increased in the year before spontaneous puberty in boys and girls, and rose further to a maximum (median, 8.3 cm/year) in the first year of puberty in boys. In girls, the maximum height velocity occurred in the year before puberty (median, 6.5 cm/year). Height velocity increased in the year before spontaneous puberty in boys and girls, and rose further to a maximum (median, 8.3 cm/year) in the first year of puberty in boys. In girls, the maximum height velocity occurred in the year before puberty (median, 6.5 cm/year). Height velocity during the first year of puberty was inversely correlated to age at puberty onset (r = -0.56, p = 0.0001). After medical induction of puberty, height velocities in the first year of puberty were 5.4 and 3.4 cm/year for boys and girls, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Does growth hormone treatment improve final height attainment of children with intrauterine growth retardation?

Twenty four children (five girls, 19 boys) who had intrauterine growth retardation were treated with daily subcutaneous biosynthetic human growth hormone, initially in a dose of either 15 or 30 U/m2/week for the first year and in the latter dose for the next two years. Six patients (one girl, five boys) had no dysmorphic signs and 18 (four girls, 14 boys) had signs of Russel-Silver syndrome. All had birth weights below the third centile when adjusted for gestation age and all the children were below the third height centile at the start of treatment. Mean age was 6.3 years (range 2.1-9.7) when growth hormone treatment was started. All had normal growth hormone secretion to either a pharmacological or physiological test. In the first year of treatment, height velocity SD score increased from -0.75 to +3.6 in the group treated with 30 U/m2/week, and from -0.77 to +1.4 in the lower dose group. After three years of treatment, mean height velocity SD score was +1.1, irrespective of which initial treatment dose had been administered during the first year. There was no difference in the growth response of children with or without dysmorphic features. However, despite the sustained increase in growth rate, there was no significant change in height for bone age SD score, pointing to an unaltered final height outcome.

Growth hormone treatment in infertility: a short review

In cultured animal granulosa cells, insulin-like growth factor 1 (IGF-1) and growth hormone (GH) have been shown to have a functional role. With the recent availability of recombinant GH, clinical studies have followed using GH in ovulation induction in patients resistant to stimulation by gonadotrophins alone. So far, patient numbers have been small in the studies conducted but the results suggest that GH may improve ovulation induction and reduce gonadotrophins requirement. However, patients with GH deficiency are not infertile. Thus the evidence suggests that the role of GH treatment in infertility is probably facilitative and not obligatory.

Management of growth hormone deficiency through puberty

As a model of the growth hormone (GH) dependence of growth in prepuberty and puberty, the growth of 182 children (93 boys, 89 girls) who survived in first remission for treatment of acute lymphoblastic leukaemia was examined. Chemotherapy regimens, including intrathecal methotrexate, were similar in all patients, but CNS treatment differed, in that one group received 2400 cGy cranial irradiation, while the other received 1800 cGy. There was a significant decrease in height SDS during prepuberty, which was equivalent in both sexes, whereas there was a much greater decrease in pubertal growth in girls than in boys. Girls treated with the lower dose regimen of cranial irradiation had their onset of pubertal maturation significantly advanced, to a mean of 9.9 years (p less than 0.001). Previous studies have indicated that the duration of puberty is shortened by GH treatment in patients with idiopathic multiple pituitary hormone deficiency or isolated GH deficiency (GHD). To determine whether an increase in the dose of GH administered during the adolescent growth spurt would improve final height, a prospective randomized trial was performed in 32 children (25 boys, 7 girls) with isolated GHD treated with a GH dose regimen of 15 IU/m2/week as daily s.c. injections. At the onset of the pubertal growth spurt, the patients were randomized either to an unchanged dose or to 30 IU/m2/week. There was no significant change in height velocity with the doubled dose of GH, but there was a trend in the advancement of pubertal maturation which was considered to be dose related. It is suggested that these findings are of relevance to the treatment of GHD in puberty, especially in girls with early or precocious puberty occurring as a consequence of low-dose cranial irradiation.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

Disturbance of growth hormone--insulin-like growth factor axis in uraemia. Implications for recombinant human growth hormone treatment

The growth hormone/insulin-like growth factor (IGF) axis is disturbed in uraemia. Elevated plasma growth hormone (GH) levels despite diminished growth suggest GH resistance, which may be due in part to a decreased expression of the growth hormone receptor at the cell membrane. The hepatic production of IGFs under the control of GH is impaired. Furthermore, there is an excess of IGF-binding protein over total IGF as a consequence of reduced renal clearance of low-molecular-weight subunits of the IGF-binding protein (IGF-BP). This results in an absolute (diminished production) and a relative (low bioavailability) deficiency of IGF. Recombinant human growth hormone (rhGH) in doses of 4 IU/m2 per day is able to induce catch-up growth in children with preterminal and terminal renal failure. The growth stimulation of exogenous GH is attributed to its potency to increase the ratio of IGF-I to IGF-BP, followed by a normalization of IGF bioactivity. In renal transplanted children growth is not only disturbed by decreased renal function but also by steroid treatment. Corticosteroids are responsible for catabolism, for suppression of pituitary GH secretion and for inhibition of local production of IGFs. Exogenous rhGH is able to counteract these growth-inhibiting effects. However, it remains to be seen whether long-term GH treatment definitely improves final adult height.