Immune function in growth hormone-deficient children treated with biosynthetic growth hormone

Conflicting data regarding the immune function in growth hormone (GH) -deficient children or changes in immune parameters during substitutive GH therapy have been reported. We have studied the immune function in 13 patients with GH deficiency before and during treatment with biosynthetic GH (12 IU/m2 body surface/week) after 6 and 12 months of therapy. We found that the absolute number of total T lymphocytes and T-cell subsets (using monoclonal Ab as markers), Natural Killer cell activity (target K562) and response of lymphocytes to polyclonal mitogens (PHA, ConA, PWM) were all in the normal range and remained so after 6 and 12 months of therapy. The absolute number of B lymphocytes was in the normal range before treatment and after 6 months of therapy but dropped significantly after 12 months of treatment. Serum immunoglobulins (IgG, IgA, IgM) did not show a parallel drop and remained normal throughout the whole study. Our GH-deficient patients did not show any undue susceptibility to infections and our data thus seem to confirm that the immune function is basically intact in these children and that it is not suppressed by GH treatment. Although a drop in B lymphocytes was observed, the normal level of immunoglobulins and the normal functional response to PWM seem to demonstrate the maintenance of a normal humoral immune response.     

Prediction of growth response in prepubertal children treated with growth hormone for idiopathic growth hormone deficiency

Several multiple regression models have been developed to predict the first-year growth response to human growth hormone (hGH) in children with growth hormone deficiency (GHD). It was the aim of this study to analyse the significance of various growth parameters for a height prediction model. Data from 148 prepubertal children with idiopathic GHD were evaluated. The prediction model was developed by means of univariate and stepwise linear regression analysis and an “all possible” regression approach using Mallow's C(p) statistics. Six out of eight selected variables had a significant influence on the first-year growth rate. The most important parameter was the difference between target height SDS and height SDS at the start of therapy (THSDS - HSDSC0), accounting for 23.95% and 25.74% of the variability. No other single variable or combination of variables was more informative than the variable THSDS - HSDSC0 alone. From these data, growth velocity for the first year of hGH treatment was estimated as 1.106 (THSDS - HSDSC0) + 6.8 cm/y ± 2.2 cm (SE), allowing a prediction for different intervals between THSDS and HSDSC0. This equation was validated in a small group of 18 GHD patients demonstrating a predicted vs. observed first-year growth rate of 9.4 ± 1.1 vs. 9.5 ± 2.6 cm/y. We conclude that the difference between THSDS and height SDS at the start of therapy is an important predictor of the first-year growth response in children treated with hGH for idiopathic GHD. Unlike in previous studies, additional parameters did not increase predictability.     

Craniofacial and acral growth responses in growth hormone-deficient children treated with growth hormone

OBJECTIVES: To investigate the effects of growth hormone (GH) therapy on craniofacial growth and body proportions in growth hormone deficient children. STUDY DESIGN: By using a cross-sectional study design, we investigated GH effects on craniofacial growth with photographic facial morphometrics, head circumference, and hand and foot size in 52 children with GH deficiency (GHD) treated with GH (0.27 mg/kg/wk) for 0.19 to 15.5 years, compared with untreated children with GHD and normal first-degree relatives. To detect disproportion and to correct for stature, age and height age (HA) SD scores were analyzed. RESULTS: Untreated subjects with GHD had retarded facial height and width (P values=.001) compared with normal controls; small head circumference for age and HA (P=.001); small hands for age (P<.001) that were large for HA (P=.003); and small feet for age (P<.001) that were normal for HA. When compared with normal controls, GH-treated subjects had proportional facial heights but narrower facial widths. Head circumference, however, increased disproportionately to height (P=.001), becoming large for stature, and increasing with duration of therapy and cumulative GH dose (P<.001). Hands and feet grew proportionately to height. CONCLUSION: Growth hormone treatment with conventional doses partially corrects craniofacial deficits and does not adversely affect hand and foot growth but appears to result in excessive head circumference growth.     

Growth impairment and growth hormone therapy in children treated for malignant brain tumours

Eighty-two children with malignant brain tumours were treated according to the “8 in 1” chemotherapy protocol in Finland during 1986 to 1993. Thirty-seven with brain tumours not involving the hypothalamic-pituitary region are still alive and tumour-free. The growth and response to growth hormone (GH) therapy in these children was analysed. Children who received craniospinal irradiation had the most severe loss of height SDS, being −1.07 within 3 years of the diagnosis. Even children with no irradiation to the hypothalamic-pituitary axis had a mean change in height SDS of −0.5 after 3 years. Fifteen of 23 children who received craniospinal irradiation and two out of eight children who received cranial irradiation have received GH therapy. A catch-up growth response to the daily GH therapy with the mean dose of 0.7 IU/kg per week was complete in 3 years (+1.87 SDS), irrespective of craniospinal irradiation, in children who were treated at prepubertal age but was seen in none of the children who had reached pubertal age. Conclusion Growth impairment and GH deficiency are common in children treated for malignant brain tumours. The response to GH therapy is good in prepubertal children in terms of increased growth velocity, although the final height is not yet known. Received: 10 September 1996 and in revised form: 28 January 1997 / Accepted: 11 February 1997     

Carbohydrate metabolism on high dose growth hormone therapy in children treated for leukaemia

The effect on carbohydrate metabolism of a high dose growth hormone (GH) regimen (1.2 U/kg per week) was assessed on 24 children who had previously been treated for leukaemia. Sixteen patients received high dose GH and eight patients received a conventional dose of GH (0.6 U/kg per week). Oral glucose tolerance tests (OGTT) were performed at baseline and after 3 months of treatment with GH. For the entire group between 0 and 3 months, there was a significant increase in mean (and standard deviation) fasting plasma glucose (0.3 +/- 0.6 mmol/L), fasting insulin level (11 +/- 26 mU/L), and 2 h insulin level (20 +/- 40 mU/L). One patient, who received a conventional dose of GH, developed substantial carbohydrate intolerance. For the entire group, there was no change in response to a carbohydrate load at 3 months as measured by the area under the plasma glucose or insulin curve. There was no significant difference between conventional and high dose groups at 3 months as assessed by these parameters. This study demonstrates that a higher dose of GH may be used in these children in an attempt to improve their final height, without increased risk of carbohydrate intolerance in the short term.     

Carbohydrate metabolism on high dose growth hormone therapy in children treated for leukaemia

Abstract The effect on carbohydrate metabolism of a high dose growth hormone (GH) regimen (1.2 U/kg per week) was assessed on 24 children who had previously been treated for leukaemia. Sixteen patients received high dose GH and eight patients received a conventional dose of GH (0.6 U/kg per week). Oral glucose tolerance tests (OGTT) were performed at baseline and after 3 months of treatment with GH. For the entire group between 0 and 3 months, there was a significant increase in mean (and standard deviation) fasting plasma glucose (0.3 ± 0.6 mmol/L), fasting insulin level (11 ± 26 mU/L), and 2 h insulin level (20 ± 40 mU/L). One patient, who received a conventional dose of GH, developed substantial carbohydrate intolerance. For the entire group, there was no change in response to a carbohydrate load at 3 months as measured by the area under the plasma glucose or insulin curve. There was no significant difference between conventional and high dose groups at 3 months as assessed by these parameters. This study demonstrates that a higher dose of GH may be used in these children in an attempt to improve their final height, without increased risk of carbohydrate intolerance in the short term.     

Changes in craniofacial development induced by growth hormone therapy in children treated with bone marrow transplantation

The effect of growth hormone (GH) treatment on craniofacial development was studied in nine children exhibiting low growth velocity after bone marrow transplantation (BMT). Comparisons were made with seven BMT children who had not received GH. Two groups of age- and sex-matched healthy children served as controls for the respective patient groups. After an average observation period of 3.5 years, the BMT children not treated with GH exhibited significantly reduced mandibular length and alveolar height (p < 0.01). The increase in mandibular length was only 30% of that found in healthy controls. Maxillary growth was less affected by BMT treatment. In the GH treated group, no significant differences were found in craniofacial growth increments compared with controls. Although exogenous GH therapy in this group of children did not induce a catch-up growth, it appears to have prevented further loss in growth potential.     

Acceleration of growth rate in growth hormone-deficient children treated with human growth hormone-releasing hormone

Twenty-four growth hormone-deficient children were treated with growth hormone releasing hormone-40 (GHRH) for 6 months or longer. GHRH (1 to 4 micrograms/kg of body weight per dose) was administered subcutaneously every 3 h (n = 10); or every 3 h overnight only (n = 10); or by twice daily injections (n = 4). Twenty-one children had an increase in growth rate during GHRH treatment. The growth velocities (mean +/- SD; cm/yr) before and during treatment were, respectively: every 3 h 3.5 +/- 1.4 versus 10.0 +/- 2.2, p = 0.0001; overnight only 3.4 +/- 1.0 versus 6.2 +/- 2.1, p = 0.008; twice daily injections 3.2 +/- 1.8 versus 7.9 +/- 2.4, p = 0.06. Using these three modes of GHRH administration, different total daily amounts of GHRH were administered. Regression analysis of average daily dose versus growth velocity revealed a correlation coefficient (r) value of 0.57, p = 0.004. Sixteen children received extended treatment for periods varying from 9 to 30 months. Of these, seven children were treated continuously for 9 months with pump overnight only and 5 for 12 months with pump every 3 h. Their growth velocities were sustained at a similar rate as those observed at 6 months. Six children received both twice daily and three hourly treatments consecutively. The growth velocities were similar during both treatments. Eleven children developed circulating antibodies to GHRH during treatment, however, all 11 had accelerated growth rates during GHRH therapy.(ABSTRACT TRUNCATED AT 250 WORDS)     

Human growth hormone therapy of non-growth hormone deficient children

With biosynthetically derived human growth hormone (hGH) available in large quantities, attempts will be made to promote growth in short children who do not fulfill the 'classical' criteria for growth hormone deficiency (GHD). By these criteria, GHD is excluded if hGH levels to pharmacological stimuli exceed a definite level. Several studies have shown that a variety of short children, who are not growth hormone deficient by these criteria, will demonstrate an increased growth rate with hGH treatment. A subpopulation of children with clinical features of GHD, delayed bone age and low somatomedin levels, have low levels of spontaneously secreted growth hormone or 'bioinactive' growth hormone. These children increase their growth rates to substitution doses of hGH. In other children whose growth disorder is not likely to be caused by a disorder in the growth hormone-somatomedin axis, growth increments are occasionally seen on higher hGH doses. Future long-term studies--carefully considering the ethics of such approaches--will have to evaluate the relationships between hGH dose and both metabolic and growth responses and side effects in children with short stature in order to define more specifically further target groups of short children who will benefit from hGH therapy.     

Prediction of the growth response of short prepubertal children treated with growth hormone

The aim of this study was to identify predictors of the growth response to growth hormone (GH) during the first 2 years of GH treatment, using auxological data and the maximum GH response (GH_max) to provocation tests. The patients were 169 prepubertal short children (27F, 142M), with Gmax values ranging from 0 to 65 mU/1. Their mean age (± SD)was8.3 ± 2.4 years (range 3-13 years), mean height SDS –3.0 ± 0.7 (range –1.5 to –6.0SDS) and mean pretreatment height velocity was normal (± 0.0 SDS) (range -1.6 to + 0.9 SDS). The increase in height SDS during the first 2 years of GH treatment (0.1 U/kg/day) varied from 0.10 to 3.75 SDS, with younger children having a better growth response. Individual growth responses correlated (p < 0.001) with GH_max (r =–0.37), age (r= -0.35), 1-year pretreatment delta SDS (r = -0.25), mid-parental height SDS (r = 0.34), height SDS at start of treatment (r =–0.22) and difference between height SDS of an individual child at the onset of GH treatment and mid-parental height expressed in SDS (diff SDS) (r = –0.43). In a multiple stepwise linear regression model, diff SDS and log GH_max were found to be the strongest predictors of the magnitude of the growth response. In the short children in this study who exhibited a broad range of GH_max values, 33% of the growth response during the first 2 years of treatment could be predicted.     

生长激素在儿科应用进展

自1985年重组人生长激素开始在生长激素缺乏症中应用以来,二十多年间其应用范围扩展至先天性卵巢发育不全综合征、小于胎龄儿、特发性矮小、慢性肾功能不全等疾病,取得良好的临床效果,总体安全性良好.但仍需注意监测治疗期间及其后可能出现的不良反应,注意严格选择使用生长激素治疗的适应证,选择治疗最佳时机和合理剂量,这样才能既获得较理想的疗效,又节省治疗费用.同时,长效生长激素及不同给药途径生长激素等的研制,使其应用更方便,增加了依从性.该文就其在临床上的应用进展做一综述.     

Final height in Swedish children with idiopathic growth hormone deficiency enrolled in KIGS treated optimally with growth hormone

Aim: To assess final height in children with growth hormone deficiency (GHD) treated with human recombinant growth hormone (GH). Methods: Final height data for 401 Swedish children with idiopathic GHD and treated with GH, included in KIGS (Pfizer International Growth Database) between 1987 and spring 2006, were analysed retrospectively. Data were grouped according to sex, age and severity of GHD. Height at entry into KIGS, at the onset of puberty and near final height were analysed between groups. Results: Groups were heterogeneous for GHD, which ranged from partial to severe. For all groups, mean final height corrected for mid‐parental height was within the normal Swedish height range. In patients with severe GHD, mean final height was almost identical to mean normal Swedish height. About 16% of patients showed disproportionality (short legs) at final height and were significantly shorter than other patients. The parents of these children also demonstrated short stature. Conclusion: Children with idiopathic GHD receiving GH replacement therapy can achieve a final height that as a group is within the normal range and all achieve a height within their genetic potential.     

Growth and thyroid function in children treated with growth hormone.

We examined the effect of growth hormone (GH) therapy on thyroid function in 57 children with isolated GH deficiency and whether this effect could influence their growth response. Thyroid function and insulin-like growth factor I levels were measured before and after 3, 6, and 12 months of recombinant-GH therapy (20 U/m2 per week, given subcutaneously), after a 1-month withdrawal from therapy, and after a further 6 months of GH administration. The serum concentration of triiodothyronine (T3) and the T3/T4 (thyroxine) ratio increased after 12 months of GH treatment, whereas total T4 and free T4 levels decreased; thyrotropin levels did not change significantly during treatment but increased after a 1-month withdrawal. After a further 6 months of GH therapy, an increase in T3 levels and in the T3/T4 ratio and a decrease in total T4 and free T4 levels were found again, and thyrotropin levels decreased. The increment in growth velocity after 12 months of therapy correlated positively with the T3/T4 ratio and negatively with total T4 and free T4 values. These data confirm in children a GH-induced enhancement of peripheral conversion of T4 to T3. This effect appears to be more evident in children who are most sensitive to GH in terms of growth-promoting activity.