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Screening for hypo- or hyperthyroidism in adults is generally done by measuring the serum thyrotropin (thyroid-stimulating hormone, TSH) concentration. This is an efficient approach in case of suspected acquired thyroid disease. However, in infants and children, congenital hypothalamus-pituitary-thyroid (HPT) axis disorders also need to be considered, including primary and central congenital hypothyroidism, and even rarer thyroid hormone receptor and transporter defects. In primary congenital hypothyroidism, TSH will be elevated, but in the other congenital HPT axis disorders, TSH is usually within the normal range. Free thyroxine (FT4) assessment is essential for the diagnosis in these conditions.Conclusion: Here we discuss a number of rare congenital HPT axis disorders in which TSH is normal, but FT4 is low, and provide a clinical algorithm to distinguish between these disorders. What is Known: ⢠A single thyroid-stimulating hormone (TSH) measurement is an appropriate screening method for primary hypothyroidism. ⢠For central hypothyroidism and rare thyroid hormone receptor and transporter defects a free thyroxine (FT4) measurement is essential for the diagnosis because TSH is usually normal. What is New: ⢠Here we present a new problem-oriented clinical algorithm including a diagnostic flow-chart for low FT4 and normal TSH in infants and children.
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Hipotiroidismo Congénito , Enfermedades de la Tiroides , Adulto , Niño , Hipotiroidismo Congénito/diagnóstico , Humanos , Lactante , Enfermedades de la Tiroides/diagnóstico , Pruebas de Función de la Tiroides , Tirotropina , TiroxinaRESUMEN
BACKGROUND: Four genetic causes of isolated congenital central hypothyroidism (CeH) have been identified, but many cases remain unexplained. We hypothesised the existence of other genetic causes of CeH with a Mendelian inheritance pattern. METHODS: We performed exome sequencing in two families with unexplained isolated CeH and subsequently Sanger sequenced unrelated idiopathic CeH cases. We performed clinical and biochemical characterisation of the probands and carriers identified by family screening. We investigated IRS4 mRNA expression in human hypothalamus and pituitary tissue, and measured serum thyroid hormones and Trh and Tshb mRNA expression in hypothalamus and pituitary tissue of Irs4 knockout mice. RESULTS: We found mutations in the insulin receptor substrate 4 (IRS4) gene in two pairs of brothers with CeH (one nonsense, one frameshift). Sequencing of IRS4 in 12 unrelated CeH cases negative for variants in known genes yielded three frameshift mutations (two novel) in three patients and one male sibling. All male carriers (n=8) had CeH with plasma free thyroxine concentrations below the reference interval. MRI of the hypothalamus and pituitary showed no structural abnormalities (n=12). 24-hour thyroid-stimulating hormone (TSH) secretion profiles in two adult male patients showed decreased basal, pulsatile and total TSH secretion. IRS4 mRNA was expressed in human hypothalamic nuclei, including the paraventricular nucleus, and in the pituitary gland. Female knockout mice showed decreased pituitary Tshb mRNA levels but had unchanged serum thyroid hormone concentrations. CONCLUSIONS: Mutations in IRS4 are associated with isolated CeH in male carriers. As IRS4 is involved in leptin signalling, the phenotype may be related to disrupted leptin signalling.
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Hipotiroidismo/genética , Proteínas Sustrato del Receptor de Insulina/genética , Leptina/metabolismo , Transducción de Señal , Tiroxina/sangre , Adolescente , Adulto , Animales , Niño , Preescolar , Femenino , Heterocigoto , Humanos , Hipotálamo/metabolismo , Lactante , Masculino , Ratones , Persona de Mediana Edad , Mutación , Linaje , Hipófisis/metabolismo , Adulto JovenRESUMEN
Congenital hypothyroidism (CH) is one of the most common preventable forms of mental retardation and since the implementation of neonatal screening programs in the mid-1970s, early detection and treatment have proven to be very successful in preventing brain damage. CH may be of thyroidal (= primary) or of hypothalamic-pituitary (= central) origin. Primary CH may be due to abnormal thyroid gland formation (dysgenesis) or defective thyroid hormone syntheses by a structurally normal gland (dyshormonogenesis). While thyroid dysgenesis is the most common form of CH, accounting for approximately 85% of cases, genetic defects are only found in a very low proportion of patients. On the other hand, thyroid dyshormonogenesis is less common, but is usually a genetic condition with autosomal recessive inheritance. In this review we provide an overview of all known monogenetic causes of primary CH, including promising new candidate genes. In addition, alternative genetic mechanisms are discussed.
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Hipotiroidismo Congénito , Humanos , Recién Nacido , Tamizaje Neonatal , Hormonas TiroideasRESUMEN
Graves' disease (GD) is the leading cause of hyperthyroidism in children. However, compared to adults GD in children is a rare condition. In a recent guideline issued by the European Thyroid Association the diagnostic evaluation and treatment of pediatric GD is described extensively. In this article we go beyond the guideline and describe the potential challenges of establishing the right etiology of thyrotoxicosis in children, illustrated by cases of thyroid hormone resistance, autonomous functioning thyroid nodules and subacute thyroiditis with a thyrotoxic phase. In addition, we report therapeutic challenges in pediatric GD such as recurrent immunological flare-ups under anti-thyroid drug (ATD) treatment, innovative ways to improve ATD compliance and the role of definitive treatment in persistent complaints of malaise under ATD treatment.
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Background: Initial evaluation of the hypothalamus-pituitary-thyroid axis is done by measuring serum free thyroxine (fT4) and thyrotropin concentrations. For correct interpretation of these measurements, reliable age-specific reference intervals (RIs) are fundamental. Since neonatal fT4 RIs conforming to the Clinical and Laboratory Standards Institute guidelines are not available for all assays, we set out to create literature-based uniform age-specific neonatal fT4 RIs that may be used for every assay. Methods: For meta-analysis of individual participant fT4 concentrations, we systematically searched MEDLINE and Embase (search date December 6, 2023; PROSPERO registration CRD42016041871). We searched for studies reporting fT4 concentrations in healthy term newborns aged 2-27 days, born to mothers without thyroid disease in iodine-sufficient regions. Authors were invited to supply data. Due to standardization differences between assays, data could not be combined for meta-analysis directly, and we attempted to normalize the data using two distinct methods. Results: We obtained 4206 fT4 concentrations from 20 studies that used 13 different assays from 6 manufacturers. First, we set out to normalize fT4 data using the mean and standard deviation of (assay-specific) adult RIs. fT4 concentrations were transformed into Z-scores, assuming a normal distribution. Using a linear mixed-effects model (LMM), we still found a significant difference between fT4 concentration across studies (p < 0.001), after this normalization. As a second approach, we normalized the fT4 concentrations using data from a method/assay comparison study. We used the relationship between the Cobas assay and the other assays as a reference point to convert all values to Cobas values. However, this method also failed to produce consistent results, with significant differences between the normalized data (LMM p < 0.001). Conclusions: We conclude that our attempts at normalizing fT4 assay results were unsuccessful. Confounders related to our unsuccessful analysis may be assay related and/or biological. These findings have significant implications for patient care, since relying on RIs from literature may result in erroneous interpretation of results. Therefore, we strongly recommend to establish local RIs for accurate interpretation of serum fT4 concentrations in neonates.
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Tiroxina , Humanos , Tiroxina/sangre , Recién Nacido , Valores de Referencia , Pruebas de Función de la Tiroides/normas , Femenino , Tirotropina/sangre , Masculino , Tamizaje Neonatal/métodosRESUMEN
INTRODUCTION: Pycnodysostosis is an extremely rare skeletal dysplasia caused by cathepsin K deficiency. It is characterized by extreme short stature with adult height (AH) in males typically less than 150 cm and in females less than 130 cm. Our objective was to evaluate the effect and safety of growth hormone (GH) treatment in 6 patients with pycnodysostosis treated according to the Dutch national pycnodysostosis guideline. CASE PRESENTATION: Six subjects (4 boys, 2 girls) presented with pycnodysostosis, treated with GH 1.4 mg/m2/day (â¼0.046 mg/kg/day) for ≥1 year. Median (IQR) age at start of GH was 10.4 years (5.7; 12.2) and median height 113.5 cm (93.3; 129.3) (-4.2 SDS [-4.8; -3.6]). All children were prepubertal at start of GH. After 1 year of GH, median height gain was 7.6 cm (6.5; 8.5) (0.3 SDS [-0.3; 0.7]). Three children are still treated with GH, and the other three subjects reached AH: 1 boy reached an AH of 157.0 cm (-3.8 SDS) after 6.3 years of GH, and 2 girls reached an AH of 138.5 cm (-5.2 SDS) after 4.8 years of GH and 148.0 cm (-3.6 SDS) after 6.4 years of GH, respectively. This last girl received additional GnRH analogue treatment. In all subjects, height SDS remained stable or improved during and after GH treatment. No serious adverse advents were found. Serum IGF-I remained below the +2 SDS. CONCLUSION: Our data suggest that GH may prevent the decline in height which can be observed in children with pycnodysostosis. Further research is needed to confirm this. Also, the effect of other growth-promoting strategies such as treatment with an additional GnRH analogue warrants further investigation.
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[This corrects the article DOI: 10.1016/j.jhepr.2023.100933.].
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Thyroid hormone (TH) is indispensable for brain development in utero and during the first 2-3 years of life, and the negative effects of TH deficiency on brain development are irreversible. Detection of TH deficiency early in life by neonatal screening allows early treatment, thereby preventing brain damage. Inborn shortage of TH, also named congenital hypothyroidism (CH), can be the result of defective thyroid gland development or TH synthesis (primary or thyroidal CH (CH-T)). Primary CH is characterized by low blood TH and elevated thyroid-stimulating hormone (TSH) concentrations. Less frequently, CH is due to insufficient stimulation of the thyroid gland because of disturbed hypothalamic or pituitary function (central CH). Central CH is characterized by low TH concentrations, while TSH is normal, low or slightly elevated. Most newborn screening (NBS) programs for CH are primarily TSH based and thereby do not detect central CH. Only a few NBS programs worldwide aim to detect both forms of CH by different strategies. In the Netherlands, we have a unique T4-TSH-thyroxine-binding globulin (TBG) NBS algorithm for CH, which enables the detection of primary and central CH. Although the necessity of central CH detection by NBS is still under debate, it has been shown that most central CH patients have moderate-to-severe hypothyroidism instead of mild and that early detection of central CH by NBS probably improves its clinical outcome and clinical care for central CH patients with multiple pituitary hormone deficiency. We are therefore convinced that detection of central CH by NBS is of utmost importance.
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Hipotiroidismo Congénito , Recién Nacido , Humanos , Hipotiroidismo Congénito/diagnóstico , Tamizaje Neonatal , Tirotropina , Tiroxina , Hormonas TiroideasRESUMEN
Background: In Down syndrome (DS), there is high occurrence of congenital hypothyroidism (CH) and subclinical hypothyroidism (SH) early in life. The etiology of CH and early SH in DS remains unclear. Previous research has shown genome-wide transcriptional and epigenetic alterations in DS. Thus, we hypothesized that CH and early SH could be caused by epigenetically driven transcriptional downregulation of thyroid-related genes, through promoter region hypermethylation. Methods: We extracted whole blood DNA methylation (DNAm) profiles of DS and non-DS individuals from four independent Illumina array-based datasets (252 DS individuals and 519 non-DS individuals). The data were divided into discovery and validation datasets. Epigenome-wide association analysis was performed using a linear regression model, after which we filtered results for thyroid-related genes. Results: In the discovery dataset, we identified significant associations for DS in 18 thyroid-related genes. Twenty-one of 30 significant differentially methylated positions (DMPs) were also significant in the validation dataset. A meta-analysis of the discovery and validation datasets detected 31 DMPs, including 29 promoter-associated cytosine-guanine dinucleotides (CpG) with identical direction of effect across the datasets, and two differentially methylated regions. Twenty-seven DMPs were hypomethylated and promoter associated. The mean methylation difference of hypomethylated thyroid-related DMPs decreased with age. Conclusions: Contrary to our hypothesis of generalized hypermethylation of promoter regions of thyroid-related genes-indicative of epigenetic silencing of promoters and subsequent transcriptional downregulation, causing biochemical thyroid abnormalities in DS-we found an enrichment of hypomethylated DMPs annotated to promoter regions of these genes. This suggests that CH and early SH in DS are not caused by differential methylation of thyroid-related genes. Considering that epigenetic regulation is dynamic, we hypothesize that the observed thyroid-related gene DNAm changes could be a rescue phenomenon in an attempt to ameliorate the thyroid phenotype, through epigenetic upregulation of thyroid-related genes. This hypothesis is supported by the finding of decreasing methylation difference of thyroid-related genes with age. The prevalence of early SH declines with age, so hypothetically, epigenetic upregulation of thyroid-related genes also diminishes. While this study provides interesting insights, the exact origin of CH and early SH in DS remains unknown.
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Metilación de ADN , Síndrome de Down , Humanos , Epigénesis Genética , Síndrome de Down/genética , Glándula Tiroides , FenotipoRESUMEN
OBJECTIVE: The Dutch Congenital hypothyroidism (CH) Newborn Screening (NBS) algorithm for thyroidal and central congenital hypothyroidism (CH-T and CH-C, respectively) is primarily based on determination of thyroxine (T4) concentrations in dried blood spots, followed by thyroid-stimulating hormone (TSH) and thyroxine-binding globulin (TBG) measurements enabling detection of both CH-T and CH-C, with a positive predictive value (PPV) of 21%. A calculated T4/TBG ratio serves as an indirect measure for free T4. The aim of this study is to investigate whether machine learning techniques can help to improve the PPV of the algorithm without missing the positive cases that should have been detected with the current algorithm. DESIGN & METHODS: NBS data and parameters of CH patients and false-positive referrals in the period 2007-2017 and of a healthy reference population were included in the study. A random forest model was trained and tested using a stratified split and improved using synthetic minority oversampling technique (SMOTE). NBS data of 4668 newborns were included, containing 458 CH-T and 82 CH-C patients, 2332 false-positive referrals and 1670 healthy newborns. RESULTS: Variables determining identification of CH were (in order of importance) TSH, T4/TBG ratio, gestational age, TBG, T4 and age at NBS sampling. In a Receiver-Operating Characteristic (ROC) analysis on the test set, current sensitivity could be maintained, while increasing the PPV to 26%. CONCLUSIONS: Machine learning techniques have the potential to improve the PPV of the Dutch CH NBS. However, improved detection of currently missed cases is only possible with new, better predictors of especially CH-C and a better registration and inclusion of these cases in future models.
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Hipotiroidismo Congénito , Aprendizaje Automático , Tamizaje Neonatal , Bosques Aleatorios , Humanos , Hipotiroidismo Congénito/diagnóstico , Tiroxina/análisis , Hormonas Glicoproteicas de Subunidad alfa/análisis , Globulina de Unión a Tiroxina/análisis , Reacciones Falso Positivas , Algoritmos , Edad Gestacional , Recién NacidoRESUMEN
We present the case of a 15-year-old girl, with a fifth cystic progression of an adamantinomatous craniopharyngioma after multiple surgeries and previous local radiotherapy. She had severe visual impairment, panhypopituitarism including diabetes insipidus, and several components of hypothalamic damage, including morbid obesity and severe fatigue. To prevent further late effects hampering her quality of survival, she was treated biweekly with intravenous tocilizumab, an anti-interleukin-6 agent, which stabilized the cyst for a prolonged time. Based on the biology of adamantinomatous craniopharyngioma, this immune-modulating treatment seems promising for the treatment of this cystic tumor in order to reduce surgery and delay or omit radiotherapy.
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Craneofaringioma , Hipopituitarismo , Neoplasias Hipofisarias , Humanos , Femenino , Niño , Adolescente , Craneofaringioma/complicaciones , Craneofaringioma/tratamiento farmacológico , Neoplasias Hipofisarias/complicaciones , Neoplasias Hipofisarias/tratamiento farmacológico , Neoplasias Hipofisarias/patología , Hipotálamo/patología , Hipopituitarismo/patologíaRESUMEN
INTRODUCTION: Temple syndrome (TS14) is a rare imprinting disorder caused by maternal uniparental disomy of chromosome 14, paternal deletion of 14q32.2, or an isolated methylation defect. Most patients with TS14 develop precocious puberty. Some patients with TS14 are treated with growth hormone (GH). However, evidence for the effectiveness of GH treatment in patients with TS14 is limited. METHODS: This study describes the effect of GH treatment in 13 children and provides a subgroup analysis of 5 prepubertal children with TS14. We studied height, weight, body composition by dual-energy X-ray absorptiometry, resting energy expenditure (REE), and laboratory parameters during 5 years of GH treatment. RESULTS: In the entire group, mean (95% CI) height SDS increased significantly during 5 years of GH treatment from -1.78 (-2.52; -1.04) to 0.11 (-0.66; 0.87). Fat mass percentage SDS decreased significantly during the first year of GH, and lean body mass (LBM) SDS and LBM index increased significantly during 5 years of treatment. IGF-1 and IGF-BP3 levels rose rapidly during GH treatment, and the IGF-1/IGF-BP3 molar ratio remained relatively low. Thyroid hormone levels, fasting serum glucose, and insulin levels remained normal. In the prepubertal group, median (interquartile range [IQR]) height SDS, LBM SDS, and LBM index also increased. REE was normal at start and did not change during 1 year of treatment. Five patients reached adult height and their median (IQR) height SDS was 0.67 (-1.83; -0.01). CONCLUSION: GH treatment in patients with TS14 normalizes height SDS and improves body composition. There were no adverse effects or safety concerns during GH treatment.
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Hormona de Crecimiento Humana , Síndrome de Prader-Willi , Niño , Adulto , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Hormona de Crecimiento Humana/uso terapéutico , Hormona de Crecimiento Humana/farmacología , Hormona del Crecimiento , Composición Corporal , Disomía Uniparental , EstaturaRESUMEN
Objective: Congenital hypothyroidism (CH) is an inborn thyroid hormone (TH) deficiency mostly caused by thyroidal (primary CH) or hypothalamic/pituitary (central CH) disturbances. Most CH newborn screening (NBS) programs are thyroid-stimulating-hormone (TSH) based, thereby only detecting primary CH. The Dutch NBS is based on measuring total thyroxine (T4) from dried blood spots, aiming to detect primary and central CH at the cost of more false-positive referrals (FPRs) (positive predictive value (PPV) of 21% in 2007-2017). An artificial PPV of 26% was yielded when using a machine learning-based model on the adjusted dataset described based on the Dutch CH NBS. Recently, amino acids (AAs) and acylcarnitines (ACs) have been shown to be associated with TH concentration. We therefore aimed to investigate whether AAs and ACs measured during NBS can contribute to better performance of the CH screening in the Netherlands by using a revised machine learning-based model. Methods: Dutch NBS data between 2007 and 2017 (CH screening results, AAs and ACs) from 1079 FPRs, 515 newborns with primary (431) and central CH (84) and data from 1842 healthy controls were used. A random forest model including these data was developed. Results: The random forest model with an artificial sensitivity of 100% yielded a PPV of 48% and AUROC of 0.99. Besides T4 and TSH, tyrosine, and succinylacetone were the main parameters contributing to the model's performance. Conclusions: The PPV improved significantly (26-48%) by adding several AAs and ACs to our machine learning-based model, suggesting that adding these parameters benefits the current algorithm.
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Hipotiroidismo Congénito , Recién Nacido , Humanos , Hipotiroidismo Congénito/diagnóstico , Tamizaje Neonatal/métodos , Aminoácidos , TirotropinaRESUMEN
INTRODUCTION: Transient or persistent hypoparathyroidism is one of the most well-known complications of total thyroidectomy and may lead to symptomatic hypocalcaemia. In children, treatment of post-thyroidectomy hypocalcaemia usually consists of postoperative calcium and/or vitamin D supplementation. In 2013, we implemented prophylactic pre-thyroidectomy calcitriol supplementation for all children undergoing total thyroidectomy at the Amsterdam UMC. The objective of this study was to evaluate the efficacy of this prophylactic calcitriol supplementation in preventing post-thyroidectomy hypocalcaemia in children. METHODS: In a retrospective case study, we included all children (age <18 years), who underwent a total or completion thyroidectomy in the Amsterdam UMC, between 2000 and 2020. Patients were divided into two groups, patients with preoperative calcitriol supplementation and those without (controls). Hypocalcaemia was defined as total serum calcium concentration of <2.0 mmol/L. The primary outcome measure was the occurrence of hypocalcaemia in the first 72 h after surgery. Secondary outcome measures were occurrence of symptomatic hypocalcaemia, need for medical intervention within the first 72 h after surgery, and length of hospitalization. RESULTS: A total of 51 patients were included; 26 with calcitriol prophylaxis and 25 controls. There was no significant difference in occurrence of hypocalcaemia (17/26 prophylaxis group; 18/25 control group). Median postoperative calcium concentrations in the first 72 h were significantly higher in the group with prophylaxis at 30-35 h (2.26 vs. 2.01 mmol/L) and 36-41 h (2.17 vs. 1.92 mmol/L). Occurrence of symptomatic hypocalcaemia, need for medical intervention, and length of hospitalization were not significantly different between the groups. CONCLUSION: Calcitriol prophylaxis resulted in somewhat higher postoperative calcium concentrations but did not reduce the occurrence of hypocalcaemia or affect clinical outcome measures such as occurrence of symptomatic hypocalcaemia and length of postoperative hospitalization.
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Hipocalcemia , Niño , Humanos , Adolescente , Hipocalcemia/etiología , Hipocalcemia/prevención & control , Tiroidectomía/efectos adversos , Calcitriol/uso terapéutico , Calcio , Estudios Retrospectivos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Hormona ParatiroideaRESUMEN
Pathogenic variants in TSHB are known to cause severe isolated central congenital hypothyroidism (CH). In this study, we present the clinical, biochemical, and genetic features of the first patient with a mild central CH phenotype. We identified a novel homozygous variant in TSHB: (Chr1: NM_000549.5):c.290A>G p.(Tyr97Cys) in a newborn girl detected by neonatal CH screening, whose central CH was initially overlooked because of misinterpretation of her plasma-free thyroxine (fT4) concentration. This report adds to the phenotypic spectrum of TSHB variants and underlines the importance of using age-specific fT4 reference intervals to diagnose central CH.
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Hipotiroidismo Congénito , Hipotiroidismo Congénito/diagnóstico , Hipotiroidismo Congénito/genética , Femenino , Homocigoto , Humanos , Recién Nacido , Tamizaje Neonatal , Valores de Referencia , Pruebas de Función de la Tiroides , Hormonas Tiroideas , Tiroxina/uso terapéuticoRESUMEN
BACKGROUND: Temple syndrome (TS14) is an imprinting disorder caused by a maternal uniparental disomy of chromosome 14 (UPD(14)mat), paternal deletion of 14q32 or an isolated methylation defect of the MEG3-DMR. Studies on phenotypical characteristics in TS14 are scarce and patients with TS14 often experience delay in diagnosis, which has adverse effects on their health. TS14 is often characterized as either Prader-Willi-like, Silver-Russell-like or as a Silver-Russell spectrum disorder. METHODS: This study describes 15 patients with TS14 who visited the Dutch Reference Center for Prader-Willi-like from December 2018 to January 2022. RESULTS: Eight patients had UPD(14)mat and seven a methylation defect. The most common symptoms were intra-uterine growth retardation (IUGR) (100%), hypotonia (100%), precocious puberty (89%), small for gestational age (SGA) birth (67%), tube feeding after birth (53%) and psycho-behavioral problems (53%). Median (interquartile range (IQR)) IQ was 91.5 (84.25; 100.0), whilst many patients were enrolled in special education (54%). The median (IQR) fat mass % (FM%) SDS was 2.53 (2.26; 2.90) and lean body mass (LBM) SDS -2.03 (-3.22; -1.28). There were no significant differences in clinical characteristics between patients with a UPD(14)mat and a methylation defect. CONCLUSIONS: Our patients share a distinct phenotype consisting of IUGR, SGA birth, precocious puberty, hypotonia, tube feeding after birth, psycho-behavioral problems and abnormal body composition with a high FM% and low LBM. Whilst similarities with Prader-Willi syndrome (PWS) and Silver-Russell syndrome (SRS) exist, TS14 is a discernible syndrome, deserving a tailored clinical approach. Testing for TS14 should be considered in patients with a PWS or SRS phenotype in infancy if PWS/SRS testing is negative.
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Isolated aldosterone synthase deficiency is a rare autosomal recessive disorder caused by pathogenic variants in CYP11B2, resulting in impaired aldosterone synthesis. We report on a neonate with isolated aldosterone synthase deficiency caused by a novel homozygous CYP11B2 variant Chr8:NM_000498.3:c.400G>A p.(Gly134Arg). The patient presented shortly after birth with severe signs of aldosterone deficiency. Interestingly, segregation analysis revealed that the patient's asymptomatic father was also homozygous for the CYP11B2 variant. Biochemical evaluation of the father indicated subclinical enzyme impairment, characterized by elevated aldosterone precursors. Apparently, this homozygous variant led to different clinical phenotypes in two affected relatives. In this manuscript we elaborate on the performed biochemical and genetic work-up and describe potential pitfalls of CYP11B2 sequencing due to its homology to CYP11B2.
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Objective: Comparison of studies on remission rates in pediatric Graves' disease is complicated by lack of uniformity in treatment protocols, remission definition, and follow-up duration. We performed a systematic review on remission rates in pediatric Graves' disease and attempted to create uniformity by recalculating remission rates based on an intention-to-treat analysis. Methods: PubMed and Embase were searched in August 2020 for studies on patients with Graves' disease: (i) 2 to 18 years of age, (ii) initially treated with methimazole or carbimazole for at least 18 months, (iii) with a follow-up duration of at least 1 year after cessation of methimazole or carbimazole. All reported remission rates were recalculated using an intention-to-treat analysis. Results: Of 1890 articles, 29 articles consisting of 24 patient cohorts were included with a total of 3057 patients (82.6% female). Methimazole or carbimazole was initially prescribed in 2864 patients (93.7%). Recalculation based on intention-to-treat analysis resulted in an overall remission rate of 28.8% (829/2880). Pooled remission rates based on treatment duration were 23.7, 31.0, 43.7, and 75% respectively after 1.5-2.5 years, 2.5-5 years, 5-6 years (two studies), and 9 years (single study) treatment duration. The occurrence of adverse events was 419 in 2377 patients (17.6%), with major side effects in 25 patients (1.1%). Conclusions: Using a standardized calculation, the overall remission rate in methimazole-treated pediatric GD is 28.8%. A few small studies indicate that longer treatment increases the remission rate. However, evidence is limited and further research is necessary to investigate the efficacy of longer treatment durations.
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Antitiroideos/uso terapéutico , Enfermedad de Graves/diagnóstico , Enfermedad de Graves/tratamiento farmacológico , Metimazol/uso terapéutico , Adolescente , Niño , Humanos , Inducción de Remisión/métodos , Resultado del TratamientoRESUMEN
Central congenital hypothyroidism (CH) is defined as thyroid hormone (TH) deficiency at birth due to insufficient stimulation by the pituitary of the thyroid gland. The incidence of central CH is currently estimated at around 1:13,000. Central CH may occur in isolation, but in the majority of cases (60%) it is part of combined pituitary hormone deficiencies (CPHD). In recent years several novel genetic causes of isolated central CH have been discovered (IGSF1, TBL1X, IRS4), and up to 90% of isolated central CH cases can be genetically explained. For CPHD the etiology usually remains unknown, although pituitary stalk interruption syndrome does seem to be the most common anatomic pituitary malformation associated with CPHD. Recent studies have shown that central CH is a more severe condition than previously thought, and that early detection and treatment leads to good neurodevelopmental outcome. However, in the neonatal period the clinical diagnosis is often missed despite hospital admission because of feeding problems, hypoglycemia and prolonged jaundice. This review provides an update on the etiology and prognosis of central CH, and a practical approach to diagnosis and management of this intriguing condition.