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Muneo Yoshibayashi, Tetsuro Kamiya, Yoshihiko Saito, Kazuwa Nakao, Kenya Nishioka, Shinji Temma, Hiroaki Itoh, Gotaro Shirakami, and Hisayuki Matsuo

Yoshibayashi M, Kamiya T. Saito Y. Nakao K, Nishioka K, Temma S, Itoh H, Shirakami G, Matsuo H. Plasma brain natriuretic peptide concentrations in healthy children from birth to adolescence: marked and rapid increase after birth. Eur J Endocrinol 1995;133:207–9. ISSN 0804–4643

The aim of the present study is to establish the normal range and to determine the developmental changes of plasma brain natriuretic peptide (BNP) concentrations in children. We measured plasma BNP concentrations as well as atrial natriuretic peptide (ANP) concentrations in 58 healthy children from birth to adolescence and in the umbilical vein of 20 healthy neonates using highly sensitive immunoradiometric assays. The plasma BNP concentration was the highest at 0 days of age and descended through maturation to be almost constant and to be at the adult level at 3 months of age. The plasma BNP concentration at 0 days of age (56.7 ± 49.6 fmol/ml; mean±sd) was 25 to 30 times higher than the adult level and 21 times higher than that in the umbilical vein (2.7 ± 1.4fmol/ml), The plasma ANP concentration at 0 days of age was not significantly different from that in the umbilical vein. The ratio of BNP to ANP was also the highest at 0 days of age (1.39 ± 0.72) and decreased through maturation to be at the adult level at 3 months of age. Thus, the plasma BNP concentration in healthy subjects showed a marked, rapid and preferential increase immediately after birth, suggesting that BNP has a physiological role distinct from that of ANP in the perinatal circulatory changes from fetus to neonate.

Muneo Yoshibayashi, Department of Pediatrics, National Cardiovascular Center, 5-7-1 Fujishirodai, Suita, Osaka 565, Japan

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Milo Zachman

In recent years, it became evident that the hypothalamo-pituitary-gonadal axis is functioning in boys already between the neonatal period and the onset of puberty. With sensitive techniques, testosterone and gonadotropines have been detected in the plasma and urine of prepubertal boys. It is now believed that, during this period of life, the axis is active, but that either the feedback mechanisms are adjusted to a different level, the hypothalamic centers being more sensitive to androgens and keeping the testicular androgen production low, or that the gonads are more refractory to the effect of gonadotropins.

The androgen levels in biological fluids from normal prepubertal boys are extremely low. It is therefore impossible to distinguish the basal values of children with defective steroid production from those of normal children. Recently, several investigators have, however, shown that stimulation of the testicular interstitial cells is possible, if human chorionic gonadotropin is administered for several

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R. G. Edwards

The presentation made by Dr. Verbickij is important in several respects. First, it is an excellent piece of work on the immunology of pregnancy. Next, it shows how a model can be established in a non-human primate to facilitate research on clinical problems.

There has been a great amount of interest in the immunology of pregnancy in recent years. The stimulus to much of the early research was the development of methods to prevent rhesus haemolytic disease in human neonates. We are all familiar with the great progress being made in these studies following the introduction of the use of anti-Rh serum (Clarke 1968). There has been a significant reduction in the incidence of afflicted children, and this progress seems bound to continue as more experience is gained on the best ways of using the antiserum.

Yet there are still many cases of sensitised mothers carrying foetuses at risk of

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J. L. C. Ch'ng, A. Kaiser, J. Lynn, and G. F. Joplin

Abstract. Total parathyroidectomy is required to cure neonatal primary hyperparathyroidism (NPH) as any parathyroid remnant quickly becomes hyperplastic, causing recurrent hypercalcaemia. We present a patient with NPH who had total removal of his eutopic parathyroid glands but continued to have parathyroid hormone secretion from presumed ectopic parathyroid tissue. Hypercalcaemia initially recurred but normal calcium homeostasis was established as the child grew older. We postulate that the underlying defect in NPH is decreased sensitivity to the serum ionic calcium feedback inhibition at the parathyroid receptor level and that this sensitivity can improve with age.

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M. H. Gons, J. H. Kok, W. H. H. Tegelaers, and J. J. M. de Vijlder

Abstract. In this paper we describe methods for the early aetiological diagnosis of congenital hypothyroidism, using beside the classical T4, T3 and TSH plasma concentrations, four additional parameters in plasma and urine. The first one is thyroglobulin (Tg). In normal children of more than one year of age and in adults, 5–35 ng/ml plasma is found, in neonates 2–3 weeks old, this level is 10–250 ng/ml. In patients with a stimulated thyroid gland, as in primary congenital hypothyroidism, plasma Tg levels increase. High Tg values are found in iodine deficiency and in organification defects. In the absence of the thyroid gland plasma Tg is undetectable. Low to normal levels are found in cases with hypoplasia of the gland. In patients with a disturbed synthesis of Tg, resulting in Tg deficiency of the gland, plasma Tg levels vary from undetectable to normal. The PBI-T4 plasma difference, which is caused by circulating abnormal iodoproteins is the second parameter. The products of thyroidal breakdown processes of the abnormal iodoproteins are excreted in the urine and used as the third parameter. We found that the excretion of this low molecular weight iodinated material (LOMWIOM) was increased only in Tg-deficient patients.

If the neonate is found to be hypothyroid, thyroid hormone substitution must be given immediately. Blood and urine sampling can be done just before or even directly after starting the therapy. The measurements extended with the determination of the total iodine excretion (fourth parameter) can be carried out within 1 week. With these additional methods it appeared to be possible to distinguish between several types of congenital hypothyroidism in neonates found by screening.

Open access

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 the 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 the incidence of CH in recent studies. Both genetic factors, in particular mutations affecting DUOX2 and DUOXA2, and environmental factors, for example, iodine deficiency and excess, anti- TSHR antibodies and exposure to antithyroid 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.

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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

Objective

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.

Results

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.

Conclusions

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.

Free access

S Bellone, F Prodam, S Savastio, D Avanzo, A Pagani, L Trovato, G E Walker, G Genoni, and G Bona

Context

Ghrelin is a peptide with multiple functions that circulates in acylated (AG) and unacylated (UAG) forms. However, the role of ghrelin in neonates (NN) remains to be clarified.

Objective

The aim of this study was to determine ghrelin concentrations of the two forms in NN to clarify their biological roles. As such, ghrelin levels at birth were compared with those in later life.

Setting and design

Tertiary Care Center. In this cross-sectional study, we evaluated AG, UAG, AG/UAG ratio, and insulin levels in venous cord blood from NN and in fasted normal weight (NW) and obese (OB) children, both prepubertal and pubertal.

Subjects

We studied 82 NN, 82 NW, and 58 OB children.

Results

AG levels were lower in NN than in NW and OB children (P<0.0001), more specifically the prepubertal NW and OB children (P<0.0001). UAG levels were higher in NN than in NW and OB children (P<0.0001). Therefore, the AG/UAG ratio was lower in NN than in NW and OB children (P<0.0001). NN showed insulin levels similar to NW and lower than OB children (P<0.0001). At birth UAG was positively correlated with AG (Pearson: 0.425; P<0.0001) and negatively with insulin (−0.253; P<0.02). In NW and OB, UAG and AG were positively correlated to each other and negatively correlated with insulin and body mass index (−0.566; P<0.0001).

Conclusions

NN compared with children, showed higher UAG and lower AG levels. The AG/UAG ratio showed a very different profile in NN, being lower than in NW and OB children, thus suggesting a different metabolic function for the two forms in NN. Further studies are needed to clarify the exact role of the different ghrelin forms in NN.

Free access

D T Ward, M Z Mughal, M Ranieri, M M Dvorak-Ewell, G Valenti, and D Riccardi

Objective

Loss-of-function calcium-sensing receptor (CAR) mutations cause elevated parathyroid hormone (PTH) secretion and hypercalcaemia. Although full Car deletion is possible in mice, most human CAR mutations result from a single amino acid substitution that maintains partial function. However, here, we report a case of neonatal severe hyperparathyroidism (NSHPT) in which the truncated CaR lacks any transmembrane domain (CaRR392X), in effect a full CAR ‘knockout’.

Case report

The infant (daughter of distant cousins) presented with hypercalcaemia (5.5–6 mmol/l corrected calcium (2.15–2.65)) and elevated PTH concentrations (650–950 pmol/l (12–81)) together with skeletal demineralisation. NSHPT was confirmed by CAR gene sequencing (homozygous c.1174C-to-T mutation) requiring total parathyroidectomy during which only two glands were located and removed, resulting in normalisation of her serum PTH/calcium levels.

Design and methods

The R392X stop codon was inserted into human CAR and the resulting mutant (CaRR392X) expressed transiently in HEK-293 cells.

Results

CaRR392X expressed as a 54 kDa dimeric glycoprotein that was undetectable in conditioned medium or in the patient's urine. The membrane localisation observed for wild-type CaR in parathyroid gland and transfected HEK-293 cells was absent from the proband's parathyroid gland and from CaRR392X-transfected cells. Expression of the mutant was localised to endoplasmic reticulum consistent with its lack of functional activity.

Conclusions

Intriguingly, the patient remained normocalcaemic throughout childhood (2.5 mM corrected calcium, 11 pg/ml PTH (10–71), age 8 years) but exhibited mild asymptomatic hypocalcaemia at age 10 years, now treated with 1-hydroxycholecalciferol and Ca2 + supplementation. Despite representing a virtual CAR knockout, the patient displays no obvious pathologies beyond her calcium homeostatic dysfunction.

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.