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Aristeidis Giannakopoulos, Alexandra Efthymiadou, and Dionisios Chrysis

Objective

The diagnosis of growth hormone deficiency (GHD) in children is not always straightforward because insulin-like growth factor 1 (IGF-I) or GH stimulation tests may not be able to discriminate GHD from constitutional delay of growth and puberty (CDGP) or other causes of short stature.

Design

Boys and girls (n = 429, 0.7–16 years) who attended our department for short stature participated in this study. They were followed up for an average period of 9 years. At the end of follow-up after reaching the final height, a definitive diagnosis was assigned, and all the components of ternary complex (IGF-I, IGF-binding protein-3 (IGFBP-3), acid-labile subunit (ALS), and IGF-I/IGFBP-3 ratio) were evaluated as biomarkers for the respective diagnosis.

Results

All the components of the ternary complex were tightly correlated with each other and were positively related to age. IGF-I, IGFBP-3, ALS, and IGF-I/IGFBP-3 ratio differed significantly between GHD and normal groups. IGF-I and ALS levels were lower in GHD compared to children with familial short stature, while IGF-I and IGF-I/IGFBP-3 ratio was significantly lower in GHD compared to children with CDGP. IGF-I and IGF-I/IGFBP-3 receiver operating curve cutoff points were unable to discriminate between GHD and normal groups or between GHD and CDGP groups.

Conclusion

Despite the tight correlation among all the components of the ternary complex, each one shows a statistically significant diagnosis-dependent alteration. There is a superiority of IGF-I, ALS, and IGF-I/IGFBP-3 ratio in the distinction between GHD and CDGP or between GHD and normal groups but without usable discriminating power, making auxology as the primary criterion for establishing the diagnosis.

Free access

Annette Mouritsen, Lise Aksglaede, Kaspar Soerensen, Casper P Hagen, J H Petersen, Katharina M Main, and Anders Juul

Background

Pubertal onset is usually defined by breast development in girls and testicular growth in boys. Pubarche is defined as the attainment of pubic hair and is considered as a sign of pubertal transition. Pubarche is preceded by a gradual increase in production of adrenal androgens, DHEA and Δ4-androstenedione (Adione), a process termed adrenarche.

Objective

To study the natural course of pubertal transition and the associations with adrenarche, body fat, and linear growth.

Design and methods

A longitudinal study of 179 healthy children (89 girls) with higher socioeconomic background examined every 6 months for 5 years. Pubic hair stage, breast stage, genital stage, testicular volume (TV), height, weight, and four skinfolds were measured.

Results

In girls, median age (25th and 75th percentiles) at thelarche (B2+) was 10.1 years (9.3–10.9). In boys, median age at attaining a TV >3 ml was 11.5 years (10.9–12.0). Median age at pubarche (PH2+) was 10.9 years (10.3–11.4) in girls and 11.6 years (10.8–12.4) in boys. Only 6.8% (4/59) of the girls and 24.6% (15/61) of the boys developed pubic hair as the first isolated sign of puberty. Serum DHEAS and Adione increased with age, although the increase in Adione was most pronounced in girls. No associations between early age at thelarche/testicular growth and increased body fat (BMI and sum of four skinfolds) were observed.

Conclusion

Danish children rarely experience pubarche as the first sign of puberty. No associations between age at pubertal onset and body composition were found. Circulating levels of Adione, but not DHEAS, increased with the onset of puberty, although with large interindividual variability.

Free access

Y Rakover, A Silbergeld, I Lavi, R Masalha, and IB Shlomo

OBJECTIVES: In the majority of children with short stature, the etiology is unknown. Mutations of the GH receptor (GHR) have been reported in a few children with apparent idiopathic short stature (ISS). These patients had low IGF-I, IGF-binding protein-3 (IGFBP-3) and GH-binding protein (GHBP), but a normal or exaggerated GH response to provocative stimuli, suggestive of partial GH insensitivity (GHI). We attempted to identify children with partial GHI syndrome, based on their response to GH provocative stimuli and other parameters of the GH-IGF-I axis. SUBJECTS AND METHODS: One hundred and sixty-four pre-pubertal children (97 boys, 67 girls) aged 7.2 (0.5-16.75) years were studied. All had short stature with height <3rd centile. The weight, bone age (BA) and body mass index (BMI) of the subjects, as well as the parents' heights and mid parental height (MPH) were assessed. Basal blood samples were taken for IGF-I, IGFBP-3 and GHBP. All subjects underwent a GH provocative test with either clonidine, arginine or insulin. The subjects were divided into three groups: (A) patients with peak GH concentration <18 mIU/l in two different provocative tests (GH deficiency - GHD, n=33); (B) patients with peak GH between 18.2 and 39.8 mIU/l (normal response, n=78); (C) patients with peak GH >40 mIU/l (exaggerated GH response, n=53). RESULTS: No significant differences were found in age, height (standard deviation score (SDS)), parental height (SDS) and the difference between chronological age and bone age (DeltaBA) between the groups. Patients with GHD were heavier (P=0.039) and had significantly higher BMI (SDS) (P=0.001) than the other groups. MPH (SDS) was lower in the group of exaggerated responders (P=0.04) compared with the other groups. No significant differences were found between the groups for the biochemical parameters when expressed nominally or in SDS, except for IGFBP-3 (SDS), which was lower in the GHD group (P=0.005). The GHBP levels were not lower in the group of exaggerated GH response to provocative stimuli. Height (SDS) correlated negatively with basal GH values in pooled data of all the subjects (r=-0.358, P<0.0001), in normal responders (r=-0.45, P<0.0001) and in the exaggerated responders (r=-0.341, P<0.0001), but not in the GHD group. CONCLUSION: Exaggerated GH response to provocative tests alone does not appear to be useful in identifying children with GHI.

Free access

Carmen Freire, Rosa Ramos, Esperanza Amaya, Mariana F Fernández, Piedad Santiago-Fernández, Maria-Jose Lopez-Espinosa, Juan-Pedro Arrebola, and Nicolas Olea

Objective

An association between thyroid function during pregnancy or infancy and neurodevelopment in children has been demonstrated. We aimed to investigate whether newborn TSH concentrations are related to subsequent neurocognitive development.

Design

We conducted a longitudinal study on 178 children from a general population birth cohort in Granada (Spain) born in 2000–2002.

Methods

TSH concentrations were measured in umbilical cord blood, and cognitive functions were assessed at 4 years of age using the McCarthy's scales of children's abilities (MSCA). Organochlorine (OC) compound concentrations and the combined oestrogenicity (total effective xeno-oestrogenic burden (TEXB)) were also determined in the placentae.

Results

Mean newborn TSH was 3.55 mU/l (range=0.24–17 mU/l). In multivariate regression analyses, adjusting for maternal and child characteristics, higher newborn TSH concentrations showed a decrease of 3.51 and 3.15 points on the MSCA general cognitive and executive function scores respectively and were associated with a higher risk of scoring below the 20th percentile (P20) on the quantitative score (odds ratio (OR)=2.64). Children with TSH in the upper quartile (4.19–17.0 mU/l) were at higher risk of scoring <P20 on span memory (OR=5.73), whereas children with TSH in the second quartile (2.05–2.95 mU/l) were at lower risk of scoring <P20 on the verbal scale (OR=0.24). Neonatal TSH status was also associated with general cognitive and executive function outcomes when controlling for prenatal exposure to OCs or placental TEXB.

Conclusions

Newborn thyroid hormone status expressed by TSH in cord blood may adversely affect later cognitive function. A more thorough screening for neonatal thyroid deficiency is warranted.

Open access

Huseyin Demirbilek, Ved Bhushan Arya, Mehmet Nuri Ozbek, Jayne A L Houghton, Riza Taner Baran, Melek Akar, Selahattin Tekes, Heybet Tuzun, Deborah J Mackay, Sarah E Flanagan, Andrew T Hattersley, Sian Ellard, and Khalid Hussain

Background

Neonatal diabetes mellitus (NDM) is a rare form of monogenic diabetes and usually presents in the first 6 months of life. We aimed to describe the clinical characteristics and molecular genetics of a large Turkish cohort of NDM patients from a single centre and estimate an annual incidence rate of NDM in South-Eastern Anatolian region of Turkey.

Design and methods

NDM patients presenting to Diyarbakir Children State Hospital between 2010 and 2013, and patients under follow-up with presumed type 1 diabetes mellitus, with onset before 6 months of age were recruited. Molecular genetic analysis was performed.

Results

Twenty-two patients (59% males) were diagnosed with NDM (TNDM-5; PNDM-17). Molecular genetic analysis identified a mutation in 20 (95%) patients who had undergone a mutation analysis. In transient neonatal diabetes (TNDM) patients, the genetic cause included chromosome 6q24 abnormalities (n=3), ABCC8 (n=1) and homozygous INS (n=1). In permanent neonatal diabetes (PNDM) patients, homozygous GCK (n=6), EIF2AK3 (n=3), PTF1A (n=3), and INS (n=1) and heterozygous KCNJ11 (n=2) mutations were identified. Pancreatic exocrine dysfunction was observed in patients with mutations in the distal PTF1A enhancer. Both patients with a KCNJ11 mutation responded to oral sulphonylurea. A variable phenotype was associated with the homozygous c.-331C>A INS mutation, which was identified in both a PNDM and TNDM patient. The annual incidence of PNDM in South-East Anatolian region of Turkey was one in 48 000 live births.

Conclusions

Homozygous mutations in GCK, EIF2AK3 and the distal enhancer region of PTF1A were the commonest causes of NDM in our cohort. The high rate of detection of a mutation likely reflects the contribution of new genetic techniques (targeted next-generation sequencing) and increased consanguinity within our cohort.

Free access

LC Foo, A Zulfiqar, M Nafikudin, MT Fadzil, and AS Asmah

OBJECTIVE: Iodine deficiency endemia is defined by the goitre prevalence and the median urinary iodine concentration in a population. Lack of local thyroid volume reference data may bring many health workers to use the European-based WHO/International Council for Control of Iodine Deficiency Disorders (ICCIDD)-recommended reference for the assessment of goitre prevalence in children in different developing countries. The present study was conducted in non-iodine-deficient areas in Malaysia to obtain local children's normative thyroid volume reference data, and to compare their usefulness with those of the WHO/ICCIDD-recommended reference for the assessment of iodine-deficiency disorders (IDD) in Malaysia. DESIGN AND METHODS: Cross-sectional thyroid ultrasonographic data of 7410 school children (4004 boys, 3406 girls), aged 7-10 years, from non-iodine-deficient areas (urban and rural) in Peninsular Malaysia were collected. Age/sex- and body surface area/sex-specific upper limits (97th percentile) of normal thyroid volume were derived. Thyroid ultrasonographic data of similar-age children from schools located in a mildly iodine-deficient area, a severely iodine-deficient area, and a non-iodine-deficient area were also collected; spot urines were obtained from these children for iodine determination. RESULTS: The goitre prevalences obtained using the local reference were consistent with the median urinary iodine concentrations in indicating the severity of IDD in the areas studied. In contrast, the results obtained using the WHO/ICCIDD-recommended reference showed lack of congruency with the median urinary iodine concentrations, and grossly underestimated the problem. The local sex-specific reference values at different ages and body surface areas are not a constant proportion of the WHO/ICCIDD-recommended reference. A further limitation of the WHO/ICCIDD-recommended reference is the lack of normative values for children with small body surface areas (<0.8m2) commonly found in the developing countries. CONCLUSION: The observations favour the use of a local reference in the screening of children for thyroid enlargement.

Free access

Ying Sun, Jiao Fang, Yuhui Wan, Puyu Su, and Fangbiao Tao

Objective

Previous finding suggests that children growing up under chronic stress tend to experience earlier sexual maturity. The present study aims to examine polygenic risk by experience interaction in predicting pubertal timing, as well as provide insight regarding the relevance of two G × E paradigms.

Design and methods

Data were analyzed from a 3-year prospective puberty cohort in Anhui Province, China. Breast Tanner stage and testicular volume (TV) of 997 children were annually assessed. The polygenic risk score (PRS) was computed based on 17 SNPs for early pubertal timing. Hair cortisol concentrations (HCC) were assessed in the first 3 cm hair segment as a biological marker of chronic stress.

Results

Comparing with participants under moderate levels of stress as measured by HCC, the puberty-accelerating effects of chronic stress were only observed among girls with moderate (1.7 months earlier, P = 0.007) and low genetic susceptibility (2.2 months earlier, P < 0.001) and among boys with high genetic susceptibility (2.0 months earlier, P = 0.005). Polygenic differences (PRSs) in age at thelarche was most prominent in those with low levels of stress by HCC (9.06, 9.36 and 9.53 years for high, moderate and low PRS, respectively; F = 105.06, P < 0.0001), while polygenic differences in age at TV ≥4 mL was strongest in those under chronic stress (10.91, 11.06 and 11.17 years for high, moderate and low PRS, respectively; F = 100.48, P < 0.0001).

Conclusion

Chronic stress predicts earlier age at pubertal onset in a sex-specific and genetic background-dependent manner. The bioecological G × E model for girls and diathesis stress model for boys in pubertal timing warrants further investigation.

Free access

LA Metherell, MO Savage, M Dattani, J Walker, PE Clayton, IS Farooqi, and AJ Clark

OBJECTIVE: Congenital isolated ACTH deficiency (IAD) is a rare inherited disorder that is clinically and genetically heterogeneous. Patients are characterised by low or absent cortisol production secondary to low plasma ACTH despite normal secretion of other pituitary hormones and the absence of structural pituitary defects. Onset may occur in the neonatal period, but may first be observed in later childhood. Recently, mutations in the TPIT gene, a T-box factor selectively expressed in developing corticotroph cells, have been found in cases of early-onset IAD. DESIGN: Here we report the screening of the TPIT gene in seven patients with IAD, four of whom had neonatal onset. METHODS: Genomic DNA was extracted and the sequences of the 8 TPIT exons and their intron/exon junctions were determined by automated sequencing. RESULTS: Two siblings with early-onset IAD were both compound heterozygotes for mutations in exons 2 and 6. The missense mutation (Met86Arg) in exon 2 within the T-box (or DNA binding domain) is predicted to disrupt DNA binding. A frameshift mutation in exon 6 (782delA) introduces a premature stop codon and is likely to lead to a non-functional truncated protein. No nucleotide changes were observed in exonic sequences in the other two early- or the three later-onset cases. Fifteen single nucleotide polymorphisms that were not predicted to change the TPIT transcript were also detected. CONCLUSIONS: These findings provide a further illustration of the genetic heterogeneity of IAD and are highly suggestive of one or more other genes being implicated in this disorder.

Free access

Jiska S Peper, Rachel M Brouwer, G Caroline M van Baal, Hugo G Schnack, Marieke van Leeuwen, Dorret I Boomsma, René S Kahn, and Hilleke E Hulshoff Pol

Objective

Brain volume of boys is larger than that of girls by ∼10%. Prenatal exposure to testosterone has been suggested in the masculinization of the brain. For example, in litter-bearing mammals intrauterine position increases prenatal testosterone exposure through adjacent male fetuses, resulting in masculinization of brain morphology.

Design

The influence of intrauterine presence of a male co-twin on masculinization of human brain volume was studied in 9-year old twins.

Methods

Magnetic resonance imaging brain scans, current testosterone, and estradiol levels were acquired from four groups of dizygotic (DZ) twins: boys from same-sex twin-pairs (SSM), boys from opposite-sex twin-pairs (OSM), girls from opposite-sex twin-pairs (OSF), and girls from same-sex twin-pairs (SSF; n=119 individuals). Data on total brain, cerebellum, gray and white matter volumes were examined.

Results

Irrespective of their own sex, children with a male co-twin as compared to children with a female co-twin had larger total brain (+2.5%) and cerebellum (+5.5%) volumes. SSM, purportedly exposed to the highest prenatal testosterone levels, were found to have the largest volumes, followed by OSM, OSF and SSF children. Birth weight partly explained the effect on brain volumes. Current testosterone and estradiol levels did not account for the volumetric brain differences. However, the effects observed in children did not replicate in adult twins.

Conclusions

Our study indicates that sharing the uterus with a DZ twin brother increases total brain volume in 9-year olds. The effect may be transient and limited to a critical period in childhood.

Free access

L Even, V Bronstein, and Z Hochberg

The mechanism of growth retardation in Turner's syndrome has not been resolved. It is often referred to as a bone dysplasia, although endocrine derangement has not been ruled out. The present study was undertaken to evaluate the maturation of individual bones of the hand and wrist in girls with Turner's syndrome and thereby obtain information which may aid in elaborating the possible mechanism of the growth retardation in girls with Turner's syndrome. Hand and wrist films of 24 girls with Turner's syndrome, 11 normal girls with short stature and 23 normal controls were evaluated, using the references of Greulich and Pyle. Each bone or epiphysis was given an individual 'age'. During childhood the Turner patients showed the greatest delay in bone age of the phalangeal bones while the least delayed were the radius and ulna (long bones) and metacarpals. The carpal bones showed intermediate retardation. This pattern and extent of maturational retardation was clearly different from that of the short stature normal group, who showed uniform retardation of all bones. During adolescence, the phalangeal bones were further retarded and the carpal bones showed a moderate retardation. The unique profile of bone maturation in Turner's syndrome suggests an insult to chondroplasia, which may be related to estrogen deficiency or to an as yet undetermined endocrine or paracrine derangement.