Growth hormone for short children--whom should we be treating and why?

The objective of this paper was to determine systematically the impact of growth hormone (GH)therapy on adult height of children with (so-called) 'idiopathic short stature' (ISS) using the Cochrane Central Register of Controlled Trials, Medline, and the bibliographic references from retrieved articles of randomised controlled trials (RCTs) and non-RCTs from 1985 to April 2010. Inclusion criteria were initial short stature (defined as height >2 standard deviation[SD] below the mean), peak growth hormone responses>10 micrograms per litre (µg/L), prepuberty, no previous growth hormone therapy, and no comorbid conditions that would impair growth. Data extracted were adult height and overall gain in height from baseline measurement in childhood.Three RCTs (115 children) met the inclusion criteria.The adult height of the GH treated children exceeded that of the controls by 0.65 SD score (~4 cm). The mean height gain in treated children was 1.2 SD score compared with 0.34 SD score in untreated children. A difference of ~1.2 cm in adult height was observed between two GH dose regimens. In the seven non-RCTs, adult height of the GH-treated group exceeded that of controls by 0.45 SD score (~3 cm).The authors conclude that 1) GH therapy in children with ISS seems effective in partially reducing the deficit in height as adults, although less so than in other conditions for which GH is licensed; treated individuals remain relatively short compared with normal height peers. 2)Individual responses to therapy are highly variable; further studies are needed to identify responders. 3) High quality evidence from long-term RCTs of GH therapy that continue until adult height is necessary to determine the ideal dosage and long-term safety.

Physiological sex steroid replacement in premature ovarian failure: randomized crossover trial of effect on uterine volume, endometrial thickness and blood flow, compared with a standard regimen.

BACKGROUND: Premature ovarian failure (POF) is currently managed by non-physiological sex steroid regimens which are inadequate at optimizing uterine characteristics. Previous short-term studies have demonstrated some benefits of a sex steroid replacement (SSR) regimen devised to replicate the physiological cycle. This study aimed to directly compare the effects of longer-term administration of physiological SSR (pSSR) and standard SSR (sSSR) regimens on the uterine volume, blood flow and endometrial thickness (ET) in women with POF. METHODS: In a controlled crossover trial, 34 women with POF were randomized to receive 12 months of 4-week cycles of transdermal estradiol and vaginal progesterone (pSSR) followed by 12 months of 4-week cycles of oral ethinylestradiol and norethisterone (sSSR), or vice versa. Each treatment period was preceded by a 2-month washout period. At 0, 3, 6 and 12 months of each treatment period, transvaginal ultrasound examined the uterine volume and ET, as primary end-points, and uterine artery resistance (UARI) and pulsatility indices (UAPI), as secondary end-points. Serum estradiol, progesterone and gonadotrophins were also measured. RESULTS: Of the 29 women eligible for the uterine analysis, 17 completed the entire study protocol, but 25 women contributed data to statistical analysis of treatment effect. There was a greater estimated mean ET with the use of pSSR (4.8 mm) compared to that with standard therapy (3.0 mm), with an estimated difference of 1.8 mm [95% confidence interval (CI), 0.7 to 2.8, P=0.002]. The estimated mean uterine volume was also greater during physiological treatment (24.8 cm(3)) than during standard treatment (20.6 cm(3)), but the estimated difference of 4.2 cm(3) (95% CI -0.4 to 8.7) was not statitsically significant, P=0.070. The small differences between the two treatments in the mean UARI and mean UAPI were not statistically significant. The estimated treatment differences were fairly constant across the treatment periods, suggesting that prolonged treatment does not increase response. CONCLUSIONS: pSSR has a greater beneficial effect upon ET in women with POF in comparison with standard therapy. A similar trend was seen for uterine volume. Further studies are required to optimize treatment and to assess pregnancy rate and outcome. Trial Registration www.ClinicalTrials.gov, NCR00732693.

Do phthalates affect steroidogenesis by the human fetal testis? Exposure of human fetal testis xenografts to di-n-butyl phthalate.

CONTEXT: Phthalates are ubiquitous environmental chemicals. Fetal exposure to certain phthalates [e.g. di-n-butyl phthalate (DBP)] causes masculinization disorders in rats, raising concern for similar effects in humans. We investigated whether DBP exposure impairs steroidogenesis by the human fetal testis. OBJECTIVE: The aim of the study was to determine effects of DBP exposure on testosterone production by normally growing human fetal testis xenografts. DESIGN: Human fetal testes (14-20 wk gestation; n=12) were xenografted into castrate male nude mice that were treated for 4-21 d with vehicle, or 500 mg/kg·d DBP, or monobutyl phthalate (active metabolite of DBP); all mice were treated with human chorionic gonadotropin to mimic normal human pregnancy. Rat fetal testis xenografts were exposed for 4 d to DBP as a positive control. MAIN OUTCOME MEASURES: Testosterone production was assessed by measuring host serum testosterone and seminal vesicle (SV) weights at termination, plus testis gene expression (rats). RESULTS: Human fetal testis xenografts showed similar survival (∼80%) and total graft weight (8.6 vs. 10.1 mg) in vehicle and DBP-exposed hosts, respectively. Serum testosterone (0.56 vs. 0.64 ng/ml; P>0.05) and SV weight (67.2 vs. 81.9 mg; P>0.05) also did not differ. Exposure to monobutyl phthalate gave similar results. In contrast, exposure of rat fetal xenografts to DBP significantly reduced SV weight and testis Cyp11a1/StAR mRNA expression and lowered testosterone levels, confirming that DBP exposure can inhibit steroidogenesis in xenografts, further validating the negative findings on testosterone production in the human. CONCLUSIONS: Exposure of human fetal testes to DBP is unlikely to impair testosterone production as it does in rats. This has important safety and regulatory implications.

Macrovascular angiopathy in children and adolescents with type 1 diabetes.

Diabetes represents one of the most common diseases globally. Worryingly, the worldwide incidence of type 1 diabetes (T1D) is rising by 3% per year. Despite the rapid increase in diabetes incidence, recent advances in diabetes treatment have been successful in decreasing morbidity and mortality from diabetes-related retinopathy, nephropathy, and neuropathy. In contrast, there is clear evidence for the lack of improvement in mortality for cardiovascular diseases (CVDs). This emphasizes the importance of focusing childhood diabetes care strategies for the prevention of CVD in adulthood. Furthermore, although most work on diabetes and macrovascular disease relates to type 2 diabetes, it has been shown that the age-adjusted relative risk of CVD in T1D far exceeds that in type 2 diabetes. As T1D appears predominantly during childhood, those with T1D are at greater risk for coronary events early in life and require lifelong medical attention. Because of the important health effects of CVDs in children and adolescents with T1D, patients, family members, and care providers should understand the interaction of T1D and cardiovascular risk. In addition, optimal cardiac care for the patient with diabetes should focus on aggressive management of traditional cardiovascular risk factors to optimize those well-recognized as well as new specific risk factors which are becoming available. Therefore, a complete characterization of the molecular mechanisms involved in the development and progression of macrovascular angiopathy is needed. Furthermore, as vascular abnormalities begin as early as in childhood, potentially modifiable risk factors should be identified at an early stage of vascular disease development.

Exaggerated adrenarche in a cohort of Scottish children: clinical features and biochemistry.

OBJECTIVE: To investigate the reported association between exaggerated adrenarche (EA) and reduced foetal growth and to identify possible risk factors for future morbidity in Scottish children with clinical features of EA. DESIGN: Three-year prospective study. MEASUREMENTS: Auxology, blood pressure (BP), biochemical analysis of blood and urine, pelvic ultrasound in girls. RESULTS: Fifty-two patients were recruited of whom one girl had nonclassical congenital adrenal hyperplasia (17-OHP 17 nmol/l) and one had insufficient blood for analysis. The final cohort comprised 42 girls of mean (SD) age 7.7 (0.99) and eight boys of 8.8 (0.67) years. Mean (SD) birth weight was 3.27 (0.49) and 3.10 (0.76) kg in girls and boys respectively. Height/weight SDS were 1.13/1.69 in girls and 1.69/1.88 in boys. Mean systolic/diastolic BP was 107.8/60.4 (50th-75th centile) in girls and 115.5/63.9 (75th-91st centile) in boys. Uterine and ovarian development was prepubertal. Median serum dehydroepiandrosterone sulphate (DHEAS) was 2.1 and 4.1 mumol/l, androstenedione 3.1 and 3.8 nmol/l in girls and boys respectively, with DHEAS within the reference range/undetectable in 18/2 and androstenedione in 12/6 patients. Fasting insulin was 9.0 and 15.0 mU/l in girls and boys respectively, with concomitant low normal SHBG. Anti-Mullerian hormone (AMH) was 15.7 pmol/l in 27 girls, compared with 5.0 pmol/l in normal girls aged 5-8 years. CONCLUSIONS: Our Scottish EA cohort showed female predominance, no evidence of reduced foetal growth, a tendency to overweight with commensurate mild hyperinsulinaemia and modest elevation of serum androgens in some patients. We have found raised AMH levels in the girls, indicating advanced ovarian follicular development.

Blood pressure in children aged 4-8 years: comparison of Omron HEM 711 and sphygmomanometer blood pressure measurements.

OBJECTIVE: To collect normal data on blood pressure (BP) in healthy children aged 4-8 and to compare measurements of BP made in the same subjects with a sphygmomanometer and a portable automated oscillometric BP monitor (Omron HEM 711 with child cuff). METHODS: Cross-sectional observational study of 764 children. BP measurements were made at school, using both a sphygmomanometer and an Omron HEM 711. Immediately after the BP measurement children were asked to state which device they preferred (if any). RESULTS: Children had no preference for whether the sphygmomanometer or the Omron was used. Bland-Altman plots showed a lack of consistency between the two methods of BP measurement. With systolic BP there was a trend for the Omron to underestimate when low and overestimate when high. CONCLUSIONS: Children were equally distributed in their preference for BP device. There was a wide variation between the two methods of BP measurement, which suggests that comparison of automated BP measurements with normative data obtained by sphygmomanometer is not valid.

Male fertility and strategies for fertility preservation following childhood cancer treatment.

Infertility in the male is a potential complication of childhood cancer treatment for long-term survivors. The risk is dependent primarily on the treatment used, but also on the underlying disease. Chemotherapy (especially alkylating agents) and radiotherapy, even in low doses, may damage the seminiferous epithelium and impair spermatogenesis in both children and adults. Leydig cell function and testosterone production are generally preserved after chemotherapy and low dose radiotherapy, whilst larger doses of radiotherapy may result in hypogonadism. Patients treated with potentially gonadotoxic treatments require regular multidisciplinary follow-up including assessment of puberty and gonadal function. Currently the only option available for fertility preservation in young males treated for cancer is semen cryopreservation. For pre-pubertal patients, techniques for fertility preservation remain theoretical and as yet unproven. These include hormonal manipulation of the gonadal environment before treatment, germ cell transplantation and testis xenografting, which have all shown promise in a variety of animal studies. Refinement of these techniques requires investigations in relevant animal models. In the present chapter we include data which suggest that the common marmoset (Callithrix jacchus) monkey, a New World primate, exhibits important parallels with human testicular development and may help us to understand why the pre-pubertal testis is vulnerable to effects of cytotoxic therapy on future fertility.

Evidence-based child health: SIGN and NICE.

Clinical medicine is a holistic attempt to provide the best care for patients. What is the relevance of evidence-based child health and guidelines in informing clinical practice? In this review, examples drawn from paediatric endocrinology practice and an outline of the (sometimes contrasting) methodologies of the National Institute for Health and Clinical Effectiveness (NICE) and the Scottish Intercollegiate Guidelines Network (SIGN) are used to inform what needs to be a continuing debate. There is regular contact and cooperation between guideline-producing bodies both nationally and internationally, but there are still many impediments to avoiding duplication. Policies and practice do not inevitably flow from research evidence and guidelines. There is an urgent need to produce evidence of the impact of guidelines, not only on changing clinical practice where appropriate, but also on improving child health.

Germ cell differentiation in the marmoset (Callithrix jacchus) during fetal and neonatal life closely parallels that in the human.

BACKGROUND: Testicular germ cell tumours (TGCT) are thought to originate from fetal germ cells that fail to differentiate normally, but no animal model for these events has been described. We evaluated the marmoset (Callithrix jacchus) as a model by comparing perinatal germ cell differentiation with that in humans. METHODS: Immunohistochemical profiling was used to investigate germ cell differentiation (OCT4, NANOG, AP-2gamma, MAGE-A4, VASA, NANOS-1) and proliferation (Ki67) in fetal and neonatal marmoset testes in comparison with the human and, to a lesser extent, the rat. RESULTS: In marmosets and humans, differentiation of gonocytes into spermatogonia is associated with the gradual loss of pluripotency markers such as OCT4 and NANOG, and the expression of germ cell-specific proteins such as VASA. This differentiation occurs asynchronously within individual cords during fetal and early postnatal life. This contrasts with rapid and synchronous germ cell differentiation within and between cords in the rat. Similarly, germ cell proliferation in the marmoset and human occurs throughout perinatal life, in contrast to rats in which proliferation ceases during this period. CONCLUSIONS: The marmoset provides a good model for normal human germ cell differentiation and proliferation. The perinatal marmoset may be a useful model in which to establish factors that lead to failure of normal germ cell differentiation and the origins of TGCT.

Growth and skeletal development in families with NOGGIN gene mutations.

INTRODUCTION: There is a scarcity of data on height as well as bone densitometry in humans with NOGGIN mutations. METHODS: In 2 families with symphalangism, anthropometry, bone densitometry and genetic analysis of the NOGGIN gene were performed. RESULTS: In family A, the height standard deviation scores of the affected father and son were -0.4 and 3.5, respectively. In family B, the height standard deviation scores of the affected father, twin daughters and another daughter were 1.7, 1.8, 2.4 and 1.8, respectively. In the children, percentage predicted bone mineral content (BMC) for height at the appendicular sites (total femur, femoral neck) was lower than at an axial site lumbar spine. In the 2 fathers, median bone mineral density at total femur and femoral neck was -0.3 standard deviation scores (-0.7, 0.2) and at lumbar spine the scores were -0.4 and 0.9. The children had median tibial and radial speed of sound velocities of -2.1 (-0.9 to -6.4) and -1.4 (-0.2 to -4.9), respectively. DNA analysis revealed a novel missense mutation in family A and family B, resulting in a Met190Val substitution and a Pro42Arg substitution, respectively. CONCLUSION: Heterozygous gene mutations in NOGGIN are associated with tall stature in children but not necessarily in adults. The appendicular BMC and speed of sound may be low in affected children but normalises by adulthood. However, axial BMC seems normal in childhood and is high in adulthood.

Undetectable salivary testosterone in young women with premature ovarian failure.

BACKGROUND: The extent of androgen deficiency in young women with premature ovarian failure (POF) is unclear. AIM: Cross-sectional study of androgen status in young women with POF. PATIENTS: Twenty women with POF: six had Turner syndrome (group A); eight had iatrogenic POF either secondary to bilateral oophorectomy or treatment of malignancy (group B); and six had idiopathic POF (group C). The median age was 30.5 years (range 19-39); in groups B and C the median duration of ovarian failure was 10.0 years (range 1-35). METHODS: After a 2-month wash-out period without sex steroid replacement (SSR), serum testosterone (T), androstenedione (A4), dehydroepiandrosterone (DHEAS), SHBG, salivary testosterone (SalT) and the free androgen index [FAI = (serum T/SHBG) x 100] were measured. RESULTS: Median serum A4 was 4.6 nmol/l (10th, 90th centiles, 3.6, 5.1) and DHEAS was 3.2 micromol/l (10th, 90th centiles, 2.3, 9.3). Although median serum T was relatively low at 1.4 nmol/l (10th, 90th centiles, 1.1, 1.7), median SHBG was also low at 34 nmol/l (10th, 90th centiles 22.2, 67.5) and the median calculated FAI was within the normal range at 3.7 (10th, 90th centiles, 2.3, 7.0). However, SalT was undetectable in almost all subjects in the three groups of POF. CONCLUSIONS: Serum T and SHBG are relatively low in young women with POF and their FAI is therefore within the normal range. However, SalT, which measures free testosterone, is consistently low to undetectable in these young women with POF. The reliability of the FAI as a marker of androgen deficiency remains questionable.

Study of growth in prepubertal asthmatics.

OBJECTIVE: The aim of this pilot study was to assess whether long standing asthma affects growth in prepubertal Egyptian children before initiation of long-term corticosteroid therapy. METHODS: Children with asthma were divided into two groups according to asthma severity, moderate (n=24) and severe (n=14) and were compared for their physical and skeletal growth with a control group (n=15) using standard deviation score (SDS) and one-way ANOVA (analysis of variance) test. RESULTS: No statistically significant differences were found between various growth parameters (weight, height, BMI, upper segment lower segment ratio, and skin fold thickness in asthmatic and normal children, although a positive correlation was found between the age at which the asthma presented and the height in all asthmatic children, r= 0.288, p= 0.036. The bone age standard deviation scores (SDS) were 0.97 mean, -0.165 and -0.572 for controls, moderate and severe asthmatics respectively (P< 0.05), and significant inter group difference between the 2 asthmatic groups (moderate and severe) and the controls was found. CONCLUSION: The authors conclude that there was no significant major effect of asthma per se on growth parameters in children, but that skeletal maturation was influenced by long standing asthma.

Pubertal stage and hypoglycaemia counterregulation in type 1 diabetes.

AIMS: To compare physiological and autonomic responses to acute hypoglycaemia in diabetic children in pre-, mid-, and post-pubertal stages of development. METHODS: Twenty seven children (8 pre-pubertal, 7 mid-pubertal, 12 post-pubertal) with type 1 diabetes were studied. Hypoglycaemia was induced by insulin infusion until an autonomic reaction (R) was identified. Counterregulatory hormone levels were measured at baseline, R, R+15, and R+30 minutes. Haemodynamic changes and sweat production were measured. RESULTS: The mean blood glucose level at R was lower in pre-pubertal than mid-pubertal children (2.0 v 2.5 mmol/l), and was positively correlated with HbA1c. Glucagon and noradrenaline responses to hypoglycaemia were minimal in all children. A brisk increase in pancreatic polypeptide (PP) concentration only occurred in post-pubertal children. Only two children showed a sweating response to hypoglycaemia. CONCLUSIONS: The blood glucose level at which sympatho-adrenal responses to hypoglycaemia were activated was associated with glycaemic control, and varied with pubertal stage. As in adults, the glucagon response to hypoglycaemia was deficient within a few years of developing diabetes. However, sweating and secretion of PP in response to hypoglycaemia did not occur until after puberty, indicating some qualitative differences from adults.

Diagnostic utility of a low-dose gonadotropin-releasing hormone test in the context of puberty disorders.

OBJECTIVES: The 10-microg gonadotropin-releasing hormone (GnRH) test assesses pituitary gonadotroph responsiveness, whereas the 100-microg dose assesses maximal secretory capacity. Our aims were to establish normative data for the low-dose test in children and to evaluate the test in diagnosing common pubertal disorders. METHODS: We retrospectively classified 107 children who underwent 10-microg GnRH tests into normal prepubertal (20 boys, 10 girls), normal early pubertal (10 boys, 16 girls), constitutional delay of puberty (CDP, 13 prepubertal boys >12 years), hypogonadotropic hypogonadism (HH, 5 prepubertal boys >12 years), central precocious puberty (CPP, 19 girls) or premature thelarche/variant (13 girls). RESULTS: Peak LH response was higher in prepubertal boys >12 years compared with younger boys (p < 0.01) but showed no further change in early puberty. CDP boys had LH responses similar to prepubertal boys >12 years. HH boys showed an absent LH response which diagnosed HH with 100% sensitivity and 96% specificity. Thelarche girls had LH:FSH peak ratios lower than normal prepubertal (p = 0.001), pubertal (p < 0.05) or CPP (p = 0.001) girls. CONCLUSIONS: We have established normative values for the low-dose GnRH test in children. The test successfully differentiated HH from CDP in boys, and contributed to the differential diagnosis of CPP and premature thelarche in girls.

Nocturnal secretory dynamics of inhibin B and testosterone in pre- and peripubertal boys.

To investigate the secretory dynamics of testosterone and inhibin B, we collected samples every 20 min from 2000 h to 0800 h in 20 boys. Boys in group 1 (n = 5) were aged less than 8 yr, group 2 (n = 5) were aged more than 8 yr but 1.5 yr or more before pubertal onset, group 3 (n = 5) were studied 1.0 yr or less before pubertal onset, and group 4 (n = 5) were in early puberty. Testosterone increased after midnight in peripubertal boys, coinciding with the onset of LH pulsatility, and showed a pulsatile pattern in 6 of 10 of these boys. Cross-correlation analysis indicated significant temporal coupling between LH and testosterone. Inhibin B was higher in groups 3 and 4, compared with groups 1 and 2 (P < 0.01) and showed a downward trend overnight with no evidence of pulsatility and no evidence of short-term interactions with LH, FSH, or testosterone. Inhibin B and LH nocturnal means were both inversely correlated with time before pubertal onset (r(s) > or = -0.85, P < 0.01). Only LH nocturnal mean and amplitude, respectively, contributed independently to prediction of testosterone and inhibin B nocturnal means, explaining 71 and 65% of their variability. We conclude that both testosterone and inhibin B are related to nocturnal LH release in peripubertal boys but over different time scales.

Cortisol responses to the insulin hypoglycaemia test in children.

AIM: To determine the timing of the peak cortisol response to the insulin hypoglycaemia (IH) test in children and to establish paediatric reference data. METHODS: We retrospectively reviewed all IH tests in a tertiary paediatric endocrine referral centre over a 6-year period. Inclusion criteria were age <16 years and adequate hypoglycaemia (glucose < or =2.0 mmol/l). Patients with an impaired hypothalamic-pituitary-adrenal axis or receiving glucocorticoid medication were excluded. Fifty-four subjects (35 males) met the criteria. Blood samples were collected at -30, 0, 20, 30, 60, 90, 120, and 150 min in relation to insulin bolus injection (0.15 U/kg) at 0 min. Glucose, cortisol, and growth hormone (GH) were measured in all samples. RESULTS: Peak cortisol and GH responses occurred by 90 min in all subjects. Peak cortisol was inversely correlated with age (rs -0.65, p<0.0001). The median (5th centile) peak cortisol value was 689 nmol/l (547 nmol/l) in children younger than 10 years as compared with 555 nmol/l (468 nmol/l) in those older than 10 years (p<0.0001). Peak cortisol was not related to peak GH (rs -0.20, p=0.15). CONCLUSIONS: Blood sampling in the IH test may be curtailed 90 min after injection. The peak cortisol response to IH is age related.

Role of the neonatal period of pituitary-testicular activity in germ cell proliferation and differentiation in the primate testis.

BACKGROUND: The neonatal period of pituitary-testicular activity (NPTA) in human males has been hypothesized to play a role in germ cell proliferation and differentiation and to be defective in cryptorchid testes. The present study was carried out to establish in the marmoset if suppression of the NPTA, by treatment with a GnRH antagonist, results in impaired germ cell proliferation and/or differentiation. METHODS: Comparison of germ cell (GC) numbers and differentiation from gonocytes to pre-spermatogonia and spermatogonia, at birth (in controls) and at the end of the NPTA in marmoset co-twin males treated from birth to age 14 weeks with vehicle or GnRH antagonist. RESULTS: From birth to age 18-24 weeks, testis weight increased approximately 5-fold and GC number approximately 10-fold, including increased numbers of gonocytes and pre-spermatogonia and the first appearance of spermatogonia. Treatment with GnRH antagonist attenuated the increase in testis weight and GC numbers, but the effect was only partial (24-30% reduction), and the relative proportions of gonocytes, pre-spermatogonia and spermatogonia in the GnRH antagonist-treated group were unchanged from control values. CONCLUSIONS: The NPTA plays only a minor, if any, role in GC proliferation and differentiation in the marmoset. The changes in GnRH antagonist-treated co-twins may reflect impaired GC survival due to withdrawal of gonadotrophin support for Sertoli cells. These findings do not support a pivotal role for the NPTA in neonatal GC development in primates.

Health consequences of obesity.

The recent epidemic of childhood obesity(1) has raised concern because of the possible clinical and public health consequences.(2,)(3) However, there remains a widespread perception among health professionals that childhood obesity is a largely cosmetic problem, with minor clinical effects. No systematic review has yet focused on the diverse array of possible consequences of childhood obesity, though older non-systematic reviews are available.(4,)(5) In addition, no review to date has considered the vast body of evidence on the health impact of childhood obesity which has been published recently. The aim of the present review was therefore to provide a critically appraised, evidence based, summary of the consequences of childhood obesity in the short term (for the child) and longer term (in adulthood).