OBJECTIVE: To evaluate longitudinal growth, pubertal development and final height in patients with congenital hypothyroidism (CH) detected by a neonatal screening programme, and to identify factors potentially affecting growth outcome. PATIENTS: Fifty-five patients (41 females) detected by neonatal screening and followed longitudinally from the time of diagnosis and treatment (25+/-5 days) up to the age of 17+/-0.5 years were evaluated retrospectively. RESULTS: Pubertal development began and progressed normally in both males and females. In boys, a testicular volume of 4 ml was reached at 11.3+/-1.0 years. In girls breast enlargement (B2) occurred at a mean age of 10.3+/-1.2 years and the mean age of menarche was 12.5+/-1.2 years. The onset and the progression of puberty were independent of the aetiology, the severity of CH and the timing of the beginning of treatment. Girls treated with an initial amount of L-thyroxine (L-T4) greater than 8 microg/kg per day showed an earlier onset of puberty (B2 9.4+/-0.9 years; menarche 11.5+/-0.8 years) compared with girls treated with a lower initial dose of L-T4 (B2 10.5+/-1.2 years; menarche 12.6+/-1.2 years; P<0.02). However, both groups attained a similar final height (-0.1+/-1.0 SDS and 0.4+/-1.0 SDS, respectively), which in both cases was above the target height (P=0.03). All the patients in the study attained a mean final height (0.1+/-1.1 SDS) within the normal range for the reference population and above the target height (-0.9+/-0.9 SDS, P<0.0001). No significant relationship was found between final height and severity of CH at diagnosis, initial L-T4 dosage or aetiology of the defect. Patients with ectopic gland, thyroid aplasia or in situ gland attained a similar mean final height (0.1+/-1.1 SDS, 0.5+/-1.0 SDS and -0.5+/-1.0 SDS, respectively), which was in all cases greater than target height (-1.0+/-0.9, -0.6+/-0.8, -0.9+/-0.8 respectively; P<0.05). CONCLUSIONS: Our results suggest that conventional management of children with CH detected by neonatal screening leads to normal sexual development and normal adult height, and that the major factor determining height in these children is familial genetic growth potential.
M Salerno, M Micillo, S Di Maio, D Capalbo, P Ferri, T Lettiero, and A Tenore
M Cools, P Hoebeke, K P Wolffenbuttel, H Stoop, R Hersmus, M Barbaro, A Wedell, H Brüggenwirth, L H J Looijenga, and S L S Drop
Most patients with NR5A1 (SF-1) mutations and poor virilization at birth are sex-assigned female and receive early gonadectomy. Although studies in pituitary-specific Sf-1 knockout mice suggest hypogonadotropic hypogonadism, little is known about endocrine function at puberty and on germ cell tumor risk in patients with SF-1 mutations. This study reports on the natural course during puberty and on gonadal histology in two adolescents with SF-1 mutations and predominantly female phenotype at birth.
Design and methods
Clinical and hormonal data and histopathological studies are reported in one male and one female adolescent with, respectively, a nonsense mutation (c.9T>A, p.Tyr3X) and a deletion of the first two coding exons (NCBI36/hg18 Chr9:g.(126306276-126307705)_(126303229-126302828)del) of NR5A1, both predicted to fully disrupt gene function.
LH and testosterone concentrations were in the normal male range, virilization was disproportionate to the neonatal phenotype. In the girl, gonadectomy at 13 years revealed incomplete spermatogenesis and bilateral precursor lesions of testicular carcinoma in situ. In the boy, at the age of 12, numerous germ cells without signs of malignancy were present in bilateral testicular biopsy specimen.
In SF-1 mutations, the neonatal phenotype poorly predicts virilization at puberty. Even in poorly virilized cases at birth, male gender assignment may allow spontaneous puberty without signs of hypogonadotropic hypogonadism, and possibly fertility. Patients with SF-1 mutations are at increased risk for malignant germ cell tumors. In case of preserved gonads, early orchidopexy and germ cell tumor screening is warranted. The finding of premalignant and/or malignant changes should prompt gonadectomy or possibly irradiation.
N Benhadi, W M Wiersinga, J B Reitsma, T G M Vrijkotte, and G J Bonsel
To examine the relationship between maternal TSH and free thyroxine (FT4) concentrations in early pregnancy and the risk of miscarriage, fetal or neonatal death.
Cohort study of 2497 Dutch women. TSH, FT4, and thyroid peroxidase antibodies concentrations were determined at first booking. Child loss was operationalized as miscarriage, fetal or neonatal death. Women with overt thyroid dysfunction were excluded.
Twenty-seven cases of child loss were observed. The mean TSH and FT4 level in the women with child loss was 1.48 mU/l and 9.82 pmol/l compared with 1.11 mU/l and 9.58 pmol/l in women without child loss. The incidence of child loss increased by 60% (OR=1.60 (95% confidence interval (CI): 1.04–2.47)) for every doubling in TSH concentration. This association remained after adjustment for smoking, age, parity, diabetes mellitus, hypertension, previous preterm deliveries, and previous preterm stillbirth/miscarriage (adjusted odds ratio=1.80 (95% CI: 1.07–3.03)). This was not true for FT4 concentrations (OR=1.41 (95% CI: 0.21–9.40); P=0.724).
In a cohort of pregnant women without overt thyroid dysfunction, the risk of child loss increased with higher levels of maternal TSH. Maternal FT4 concentrations and child loss were not associated.
Carmen Freire, Rosa Ramos, Esperanza Amaya, Mariana F Fernández, Piedad Santiago-Fernández, Maria-Jose Lopez-Espinosa, Juan-Pedro Arrebola, and Nicolas Olea
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.
We conducted a longitudinal study on 178 children from a general population birth cohort in Granada (Spain) born in 2000–2002.
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.
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.
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.
C Ankarberg-Lindgren, E Norjavaara, and KA Wikland
OBJECTIVE: To determine whether there is evidence for impaired testicular function at final height in short boys treated with growth hormone (GH) during their childhood and adolescence. STUDY DESIGN: The analysis was restricted to males who had isolated GH deficiency or idiopathic short stature, and who were included in the Swedish National Registry and the Swedish GH trials. The subjects had to have been treated with GH for at least 4 years; the treatment had to have been started prepubertally, given for at least one year before the onset of puberty and the subjects had to have reached final height. One hundred and eleven boys fulfilled the criteria. METHODS: Testicular volumes were determined by orchidometer in each boy when GH treatment was started and at final height. Samples for testosterone measurements were collected from 77 boys at final height, and were measured by RIA. RESULTS: Each subject had normal testicular size (15 ml or more) and for those in whom concentrations were determined, serum testosterone levels and diurnal rhythm were normal. CONCLUSIONS: The results of our survey do not show evidence of testicular impairment following GH therapy.
C Evans, NJ Jordan, G Owens, D Bradley, M Ludgate, and R John
OBJECTIVE: We describe an infant with surprisingly severe neonatal hypothyroidism due to transplacental passage of thyrotrophin receptor (TSH-R)-blocking antibodies (TBAb). DESIGN AND METHODS: TBAb were detected using a cell line which stably expresses the human TSH-R and a cAMP-responsive luciferase reporter by their ability to inhibit TSH-stimulated luciferase expression. Potent TBAb were detected in maternal serum and initially in the infant's serum but, in the latter, TBAb decreased over time to within the reference range by 3-4 months of age, illustrating the transient nature of this condition. RESULTS: The thyroid function of this child did not return to normal on withdrawal of thyroxine therapy at 16 months of age when he developed transient compensated hypothyroidism. CONCLUSIONS: We propose that the presence of potent TBAb in utero and in the first weeks of life may have implications for the development of a normally sized thyroid gland. We have demonstrated the presence of TBAb in the mother's milk and, as far as we are aware, this is the first such report. However, the TBAb in the milk probably did not contribute significantly to hypothyroidism in the child, given the reducing antibody titre in his circulation.
Helton Estrela Ramos, Melina Morandini, Aurore Carré, Elodie Tron, Corinne Floch, Laurent Mandelbrot, Nathalie Neri, Benoit De Sarcus, Albane Simon, Jean Paul Bonnefont, Jeanne Amiel, Isabelle Desguerre, Vassili Valayannopoulos, Mireille Castanet, and Michel Polak
Monocarboxylate transporter 8 (MCT8 or SLC16A2) mutations cause X-linked Allan–Herndon–Dudley syndrome. Heterozygous females are usually asymptomatic, but pregnancy may modify thyroid function and MCT8 is expressed in the placenta, suggesting that maternal and fetal abnormalities might develop even in the absence of MCT8 fetal mutation. Genetic counseling is so far based on X-linked transmission, and prenatal diagnosis is rarely performed.
To describe thyroid function and the prenatal diagnosis in pregnant mothers harboring heterozygous MCT8 mutations and management of the persistent maternal hypothyroxinemia.
Two women heterozygous for MCT8 mutations (c.1690G>A and c.1393-1G>C) were monitored throughout pregnancy.
Prenatal diagnosis included sex determination, direct MCT8 sequencing, and familial linkage analysis. Ultrasonography and hormonal assays for maternal thyroid function evaluation were performed serially during pregnancy. Neonatal thyroid hormonal status was assessed.
None of the three fetuses (two males and one female) carried MCT8 mutations. One of the two heterozygous mothers revealed gestational hypothyroxinemia, prompting early levothyroxine (l-T4) therapy until delivery. The second heterozygous mother showed normal thyroid function but was preventively traited by l-T4 and all of the three neonates had normal thyroid hormone levels and thyroid gland at birth, suggesting advantages of prenatal care and/or compensatory mechanisms.
Heterozygous MCT8 women should be monitored for requirement of l-T4 therapy to prevent fetal and neonatal hypothyroidism and to avoid risk of potential cognitive delay due to gestational hypothyroxinemia. Moreover, when the disease-causing mutation is known and/or the first child is affected, prenatal diagnosis for male fetuses should be assessed early for MCT8 mutations by direct sequencing.
Kaspar Sørensen and Anders Juul
Early pubertal timing is consistently associated with increased BMI percentile-for-age in pubertal girls, while data in boys are more ambiguous. However, higher BMI percentile-for-age may be a result of the earlier puberty per se rather than vice versa. The aim was to evaluate markers of adiposity in relation to pubertal timing and reproductive hormone levels in healthy pubertal boys and girls.
Population-based cross-sectional study (The Copenhagen Puberty Study). Eight-hundred and two healthy Caucasian children and adolescents (486 girls) aged 8.5–16.5 years participated. BMI and bioelectric impedance analyses (BIA) were used to estimate adiposity. Clinical pubertal markers (Tanner stages and testicular volume) were evaluated. LH, FSH, estradiol, testosterone, SHBG and IGF1 levels were determined by immunoassays.
In all age groups, higher BMI (all 1 year age-groups, P≤0.041) was found with early compared with late maturation, despite similar BIA–estimated body fat percentage (BIA–BF%). Neither BMI nor BIA–BF% differed for a given stage of maturation. BMI percentile-for-age and prevalence of overweight/obesity were higher in the early compared with late matured pubertal children (all P≤0.038), despite similar BIA–BF%. Pubertal girls with BIA–BF >29% had significantly lower LH and FSH levels compared with normal-weight girls (P≤0.041).
Early maturational timing was not associated with higher adiposity for a given stage of puberty. Using BMI percentile-for-age overestimated the degree of adiposity in early pubertal compared with late pubertal children.
Catherine Peters and Nadia Schoenmakers
Transient congenital hypothyroidism (TCH) refers to congenital hypothyroidism which spontaneously resolves in the first few months or years of life. Currently, there is a paucity of reliable markers predicting TCH at diagnosis, and the diagnosis is established following withdrawal of levothyroxine therapy around 3 years of age. The incidence of TCH is increasing, and it is a major contributor to the overall increase in incidence of CH in recent studies. Both genetic factors, in particular mutations affecting DUOX2 and DUOXA2, and environmental factors, e.g iodine deficiency and excess, anti- TSHR antibodies and exposure to anti-thyroid or iodine-rich medications may cause TCH. Resolution of TCH in childhood may reflect both normal thyroid physiology (decreased thyroid hormone biosynthesis requirements after the neonatal period) and clearance or cessation of environmental precipitants. The relative contributions and interactions of genetic and environmental factors to TCH, and the extent to which TCH may be prevented, require evaluation in future population-based studies.
J Kratzsch, A Deimel, A Galler, T Kapellen, A Klinghammer, and W Kiess
OBJECTIVE: We investigated whether or not serum levels of the soluble leptin receptor (sOB-R) and leptin are related to anthropometric and metabolic changes during pubertal development of children and adolescents with type 1 diabetes mellitus. DESIGN AND METHODS: Blood levels of sOB-R, leptin and HbA1C, as well as body-mass index (BMI), diabetes duration and daily insulin doses, were determined in 212 (97 girls; 115 boys) children with type 1 diabetes mellitus and compared with the sOB-R serum levels in 526 healthy children and adolescents. RESULTS: OB-R serum levels and parallel values of the molar ratio between sOB-R and leptin were significantly higher in children with diabetes than in normal children (P<0.05) in almost all investigated Tanner stages. Furthermore, in the entire group of patients, we demonstrated statistically significant correlations (P<0.02) between sOB-R and the duration of diabetes (r=0.30), HbA1c levels (r=0.32) and the insulin dose (r=0.18). Multiple-regression analysis revealed that HbA1c (12.4%), height (7.9%) and duration of diabetes (8.7%) contributed to 29% variance of sOB-R in diabetic children. CONCLUSIONS: Our data suggest that poor glycemic control in diabetes may lead to increased serum levels of sOB-R. This regulation of sOB-R appears to be independent of leptin, but may have an impact on leptin action. The consequently developing molar excess of sOB-R related to leptin could reduce leptin sensitivity and may, therefore, influence leptin-related anthropometric and metabolic abnormalities.