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Objectives Elevated free T3 (FT3) is an important feature for the early diagnosis of several diseases among which Grave’s disease or Allan-Hernon-Dudley syndrome. However, there is a lack of age-adapted reference intervals for plasma thyroid hormones in children. We conducted a study to define reference values of peripheral FT3 in children using a commonly used automated immunoassay. Methods All thyroid function test (TFT) results from our lab collected during 9 months were extracted anonymously, and reference intervals establishment followed recommendations validated by International Federation of Clinical Chemistry (IFCC). Results We defined five reference intervals covering the whole pediatric period. Overall, 26.1% of peripheral FT3 measured in children with normal TSH are out of the adult reference range, and 22.2% are upper it leading to misinterpretation. In a 9-month old patient with severe neurodevelopmental disorders, a pathological elevated FT3 has been securely interpreted using the newly established interval. Conclusions The study highlights the poor relevance of adult intervals in pediatric cares, as it confirms that plasmatic FT3 is higher during the whole pediatric period. This work reports useful age-adapted reference intervals for free T3 in pediatrics using a widely used electrochemiluminescent Immunoassay (ECLIA) kit.

Design Thyroid-stimulating hormone deficiency (TSHD) is a rare disease. It may be isolated, secondary to abnormalities of genes involved in TSH biosynthesis, or associated with other pituitary deficits or abnormalities of genes involved in pituitary ontogenesis. Several genes are involved in thyrotroph development and function. Objective Our aim was to determine the genetic causes of TSHD, either isolated (ITSHD) or associated with somatotroph deficiency (TSHD-GHD), in the cohort of patients from the GENHYPOPIT network. Methods Next-generation sequencing (NGS) analyses were performed as a panel of genes on a cohort of patients with non-syndromic ITSHD or TSHGHD. The variants were classified according to the American College of Medical Genetics classification reviewed by the NGS-Diag network and correlated with the phenotype. Class 3, 4, and 5 single-nucleotide variants were checked by Sanger sequencing and copy number variants by multiplex ligation-dependent probe amplification (MLPA). Results A total of 64 index cases (22 ITSHD and 42 TSHD-GHD) were included in this cohort. A genetic cause was identified in 26.5% of patients, with 36.3% in the ITSHD group (variants in TSHβ and IGSF1) and 21.4% in TSHD-GHD (variants in IGSF1, TSHβ, TRHR, GH1, POU1F1, and PROP1). Among the pathogenic and likely pathogenic variants identified, 42% were in IGSF1, including six not previously reported. Conclusion Our results show that IGSF1 variants represent the most frequent aetiology of TSH deficiency. Despite a systematic NGS approach and the identification of new variants, most patients remain without a molecular diagnosis. Larger scale studies, such as exome or genome studies, should be considered in the future.

Objectives To examine the changes in diagnostic practices and clinical management of patients with 5α-reductase type 2 (SRD5A2) or 17β-hydroxysteroid dehydrogenase type 3 (HSD17B3) deficiency since molecular diagnoses became available. Methods Clinical, laboratory, and therapeutic data were retrieved from the medical records of 52 patients with a molecular diagnosis of SRD5A2 (n = 31) or HSD17B3 (n = 21) deficiency. Temporal trends regarding age at assessment and initial sex assignment over 1994–2020 were qualitatively analyzed. Age at molecular diagnosis was compared between two subgroups of patients according to their year of birth. Results Fifty-eight percent (n = 30) patients were diagnosed during the perinatal period, 33% (n = 17) during infancy, and 9% (n = 5) during adolescence or adulthood. Over the studied period, the patients’ age at initial assessment and diagnosis frankly decreased. The median (range) age at diagnostic confirmation was 10.5 (0–53.2) years for patients born before 2007 and 0.4 (0–9.3) years for those born in 2007 or later (P = 0.029). Genetic testing identified 27 different variants for the SRD5A2 gene (30% novel, n = 8) and 18 for the HSD17B3 gene (44% novel, n = 8). Before 2002, most patients were initially assigned as females (95%, n = 19), but this proportion dropped for those born later (44%, n = 14; P < 0.001). The influence of initial genital appearance on these decisions seemingly decreased in the most recent years. Therapeutic interventions differed according to the sex of rearing. Ten percent (n = 2) patients requested female-to-male reassignment during adulthood. Conclusion This study showed, over the past two decades, a clear trend toward earlier diagnosis and assignment of affected newborns as males.

Introduction: Maternal TSH receptor antibodies (TRAbs) can cross the placenta and affect fetal and neonatal thyroid function. Maternal TSH receptor-blocking antibodies (TBAbs) are a rare cause of congenital hypothyroidism. Case Report: Following the discovery of a highly elevated TSH on her neonatal screening test, a 10-day-old girl with no familial history of thyroid disorder was referred to the pediatric endocrinology unit. Hypothyroidism was confirmed with a highly elevated TSH (817 mIU/L, reference range 0.4–3.1) and very low levels of FT4 (1.8 pmol/L, reference range 12–22). Anti-TPO antibodies were at 81 IU/mL (reference range Conclusion: We report herein a case of transient congenital hypothyroidism with a normal neonatal TRAbs level. In case of maternal TBAbs, similar activity of maternal TBAbs must be expected in the neonate, independently of the neonatal level of TRAbs.

Les hyperthyroidies durant la grossesse sont a 90 % dues a une thyrotoxicose gestationnelle ou une maladie de Basedow mais d’autres etiologies sont a evoquer en seconde intention. Une cause rare d’hyperthyroidie gestationnelle liee a une mutation du gene codant pour le recepteur de la TSH (TSH-R) a ete decrite en 1998. Depuis, seulement une nouvelle patiente a ete diagnostiquee malgre de nombreuses demandes de sequencage. Nous rapportons ici le deroulement de sa seconde grossesse. La patiente a consulte a 7 semaines d’amenorrhee (SA) pour asthenie, tachycardie, vomissements et perte de 8 kg en un mois. La T4 libre etait superieure a 5 fois la normale, les anticorps anti-TSH-R negatifs et le taux d’hCG normal pour le terme. Malgre un traitement par propyl-thio-uracile jusqu’a 300 mg par jour, propranolol et metoclopramide, l’hyperthyroidie a ete difficile a controler avec des vomissements incoercibles et une perte de poids de 15 kg a 14 SA. Comme lors de la premiere grossesse, le traitement antithyroidien de synthese a du etre maintenu durant toute la grossesse jusqu’a l’accouchement en urgence pour une pre-eclampsie a 33 SA. L’echographie n’avait pas retrouve de goitre fœtal et le bilan thyroidien de l’enfant etait normal a la naissance. Une mutation du TSH-R doit etre evoquee devant un hyperemesis persistant au-dela de 14 semaines d’amenorrhee avec un taux d’hCG normal pour le terme et des anticorps anti-TSH-R negatifs. Cette mutation responsable d’une hyperthyroidie severe, se reproduisant a chaque grossesse et imposant une prise en charge specifique et rapprochee reste probablement sous-diagnostiquee.

Background Deficient nucleotide excision repair (NER) activity causes a variety of autosomal recessive diseases including xeroderma pigmentosum (XP) a disorder which pre-disposes to skin cancer, and the severe multisystem condition known as Cockayne syndrome (CS). In view of the clinical overlap between NER-related disorders, as well as the existence of multiple phenotypes and the numerous genes involved, we developed a new diagnostic approach based on the enrichment of 16 NER-related genes by multiplex amplification coupled with next-generation sequencing (NGS). Methods Our test cohort consisted of 11 DNA samples, all with known mutations and/or non pathogenic SNPs in two of the tested genes. We then used the same technique to analyse samples from a prospective cohort of 40 patients. Multiplex amplification and sequencing were performed using AmpliSeq protocol on the Ion Torrent PGM (Life Technologies). Results We identified causative mutations in 17 out of the 40 patients (43 %). Four patients showed biallelic mutations in the ERCC6(CSB) gene, five in the ERCC8(CSA) gene: most of them had classical CS features but some had very mild and incomplete phenotypes. A small cohort of 4 unrelated classic XP patients from the Basque country (Northern Spain) revealed a common splicing mutation in POLH (XP-variant), demonstrating a new founder effect in this population. Interestingly, our results also found ERCC2(XPD), ERCC3(XPB) or ERCC5(XPG) mutations in two cases of UV-sensitive syndrome and in two cases with mixed XP/CS phenotypes. Conclusions Our study confirms that NGS is an efficient technique for the analysis of NER-related disorders on a molecular level. It is particularly useful for phenotypes with combined features or unusually mild symptoms. Targeted NGS used in conjunction with DNA repair functional tests and precise clinical evaluation permits rapid and cost-effective diagnosis in patients with NER-defects. Electronic supplementary material The online version of this article (doi:10.1186/s13023-016-0408-0) contains supplementary material, which is available to authorized users.

Background: In congenital adrenal hyperplasia (CAH), adjusting hydrocortisone dose during childhood avoids reduced adult height. However, there are currently no CAH-specific charts to monitor growth during treatment. Our objective was to elaborate growth reference charts and bone maturation data for CAH patients. Methods: We conducted a retrospective observational cohort study, in 34 French CAH centers. Patients were 496 children born 1970–1991 with genetically proven 21-hydroxylase deficiency. Their growth and bone maturation data were collected until age 18 together with adult height, puberty onset, parental height, and treatment. The mean (SD) heights were modeled from birth to adulthood. The median±1 SD and ±2 SDs model-generated curves were compared with the French references. A linear model for bone maturation and a logistic regression model for the probability of short adult height were built. Results: Growth charts were built by sex for salt wasting (SW) and simple virilizing (SV) children treated before 1 year of age. In girls and boys, growth was close to that of the general French population up to puberty onset. There was almost no pubertal spurt and the mean adult height was shorter than that of the general population in girls (−1.2 SD, 156.7 cm) and boys (−1.0 SD, 168.8 cm). Advanced bone age at 8 years had a strong impact on the risk of short adult height (OR: 4.5 per year advance). Conclusions: The 8-year bone age is a strong predictor of adult height. It will help monitoring the growth of CAH-affected children.

Kallmann syndrome characterised by hypogonadotropic hypogonadism (HH) and anosmia is genetically heterogeneous with X-linked, autosomal dominant and autosomal recessive forms. The autosomal dominant form due to loss of function mutation in the fibroblast growth factor receptor 1 (FGFR1) accounts for about 10% of cases. We report here three paediatric cases of Kallmann syndrome with unusual phenotype in two unrelated patients with severe ear anomalies (hypoplasia or agenesis of external ear) associated with classical features, such as cleft palate, dental agenesis, syndactylia, micropenis and cryptorchidism. We found de novo mutation in these two patients (Cys178Ser and Arg622Gly, respectively), and one inherited Arg622Gln mutation with intrafamilial variable phenotype. These genotype–phenotype correlations indicate that paediatric phenotypic expression of FGFR1 loss of function mutations is highly variable, the severity of the oro-facial malformations at birth does not predict gonadotropic function at the puberty and that de novo mutations of FGFR1 are relatively frequent.

Targeted disruption of the orphan nuclear receptor SF1 results in the absence of adrenals and gonads, establishing that this transcription factor is implicated in gonadal determination and adrenal development. Four human SF1 gene mutations have been described to date: three (G35E, R92Q, R255L) were responsible for adrenal insufficiency associated with a gonadal dysgenesis in two 46, XY individuals, one (8 bp deletion in exon 6) resulted in gonadal dysgenesis without adrenal insufficiency. We identified a new heterozygous SF1 gene mutation, C16X, in a 46, XY patient showing gonadal dysgenesis with normal adrenal function: low basal levels of AMH and testosterone (T), weak T response to hCG, hypoplastic testes with abundant seminiferous tubules but rare germ cells. This mutation causes premature termination of translation and should abolish all SF1 activity. Therefore haploinsufficiency could explain the deleterious effect of this mutation in our patient suggesting that testis development is more SF1 dose-dependant than adrenal development. Although the same mechanism explains the deleterious effects of SF1 missense mutations, recent studies have demonstrated an additional dominant negative effect. These data suggest that heterozygous mutation impaired adrenal development only if the two mechanisms, gene dosage and dominant negative effects occur.

ContextHyperthyroidism occurs in 1% of neonates born to mothers with active or past Graves' disease (GD). Current guidelines for the management of GD during pregnancy were based on studies conducted with first-generation thyroid-binding inhibitory immunoglobulin (TBII) assays.ObjectiveThis retrospective study was conducted in order to specify the second-generation TBII threshold predictive of fetal and neonatal hyperthyroidism, and to identify other factors that may be helpful in predicting neonatal hyperthyroidism.MethodsWe included 47 neonates born in the Lyon area to 42 mothers harboring measurable levels of TBII during pregnancy. TBII measurements were carried out in all mothers; bioassays were carried out in 20 cases.ResultsNine neonates were born with hyperthyroidism, including five with severe hyperthyroidism requiring treatment. Three neonates were born with hypothyroidism. All hyperthyroid neonates were born to mothers with TBII levels >5 IU/l in the second trimester (sensitivity, 100% and specificity, 43%). No mother with TSH receptor-stimulating antibodies (TSAb measured by bioassay) below 400% gave birth to a hyperthyroid neonate. Among mothers of hyperthyroid neonates, who required antithyroid drugs during pregnancy, none could stop treatment before delivery. Analysis of TBII evolution showed six unexpected cases of increasing TBII values during pregnancy.ConclusionMaternal TBII value over 5 IU/l indicates a risk of neonatal hyperthyroidism. Among these mothers, a TSAb measurement contributes to identify more specifically those who require a close fetal thyroid ultrasound follow-up. These results should be confirmed in a larger series.

Objective To describe the action of prenatal dexamethasone (PreDex) on the anatomy of female congenital adrenal hyperplasia (CAH) genitalia when started at later stages of gestation. Materials and methods Our group follows a large cohort of French CAH patients who underwent PreDex therapy, of whom 258 were recently reported. Four 46,XX patients with a delayed PreDex treatment presented with a virilized genitalia and required surgical reconstruction. This is a retrospective report on genital phenotyping at the time of surgery of these four patients who began PreDex therapy at 8, 12, 20, and 28 weeks of gestation. Results Although this series is limited in number, the anatomical description of the length of the genital tubercle, the height of the urethra–vaginal confluence, and the degree of fusion of the genital folds seems to be dependent upon the starting date of PreDex. Most PreDex treatments prescribed up to now have covered the full duration of gestation. Conclusions Our findings suggest that PreDex therapy could be limited to the period of the partitioning window. It is hoped that further prospective multicentric clinical studies will obtain ethical approval in order to elucidate the place and protocols of PreDex therapy in the management of CAH.

Les cancers gynecologiques comprennent l’ensemble des tumeurs malignes de l’appareil genital feminin (vulve, vagin, col uterin, corps uterin, ovaires) ainsi que les cancers mammaires. Tres frequents chez l’adulte ou leur incidence augmente avec l’âge, ils sont rares chez l’enfant. a titre d’exemple, l’incidence aux Etats-Unis en 2005 des cancers genitaux feminins (hors cancer du sein) etait de 0,78 pour 100 000 filles âgees de moins de 20 ans contre 443 dans la population de plus de 20 ans. Sur le plan anatomopathologique, les cancers gynecologiques pediatriques sont essentiellement representes par les tumeurs germinales malignes (TGM) et les rhabdomyosarcomes (RMS). Les carcinomes sont tres rares chez l’enfant, alors que c’est l’histologie la plus frequente des cancers gynecologiques de l’adulte. Les tumeurs gynecologiques non malignes ne seront pas abordees ici.