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BACKGROUND: Aortic root dilation is a major complication of Marfan syndrome and is one of the most important criteria in establishing the diagnosis. Currently, different echocardiographic nomograms are used to calculate aortic root Z-scores. The aim of the present study was to assess the potential differences in aortic root measurements when aortic root Z-scores were obtained in a cohort of paediatric Marfan patients using several published nomograms. METHODS: In a cohort of 100 children with Marfan syndrome, Z-scores for aortic root dimensions were calculated according to the nomograms of Pettersen et al, Gautier et al, Colan et al, and Lopez et al. Bland-Altman plots were used to estimate mean differences in Z-scores and to establish limits of agreement. RESULTS: The mean Z-score of the sinus of Valsalva for Lopez et al was significantly higher compared to Gautier et al (p < 0.01) and Pettersen et al (p = 0.03). The nomogram of Lopez et al resulted in substantially higher Z-scores in patients with a large sinus of Valsalva diameter. Thirty-five percentage of the studied patients would have a Z-score ≥ 2 using Lopez et al compared to 20% for Pettersen et al, 21% for Gautier et al, and 33% for Colan et al. CONCLUSION: The currently available nomograms for calculating Z-scores of aortic dilation in children with Marfan syndrome lead to clinically relevant differences in Z-scores, especially in children with a relative large aortic root diameter. This could have impact on both the diagnosis and treatment of patients with Marfan syndrome.
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Doenças da Aorta , Síndrome de Marfan , Aorta/diagnóstico por imagem , Criança , Ecocardiografia , Humanos , Síndrome de Marfan/complicações , Síndrome de Marfan/diagnósticoRESUMO
N-Acetylglucosamine (O-GlcNAc) transferase (OGT) regulates protein O-GlcNAcylation, an essential and dynamic post-translational modification. The O-GlcNAc modification is present on numerous nuclear and cytosolic proteins and has been implicated in essential cellular functions such as signaling and gene expression. Accordingly, altered levels of protein O-GlcNAcylation have been associated with developmental defects and neurodegeneration. However, mutations in the OGT gene have not yet been functionally confirmed in humans. Here, we report on two hemizygous mutations in OGT in individuals with X-linked intellectual disability (XLID) and dysmorphic features: one missense mutation (p.Arg284Pro) and one mutation leading to a splicing defect (c.463-6T>G). Both mutations reside in the tetratricopeptide repeats of OGT that are essential for substrate recognition. We observed slightly reduced levels of OGT protein and reduced levels of its opposing enzyme O-GlcNAcase in both patient-derived fibroblasts, but global O-GlcNAc levels appeared to be unaffected. Our data suggest that mutant cells attempt to maintain global O-GlcNAcylation by down-regulating O-GlcNAcase expression. We also found that the c.463-6T>G mutation leads to aberrant mRNA splicing, but no stable truncated protein was detected in the corresponding patient-derived fibroblasts. Recombinant OGT bearing the p.Arg284Pro mutation was prone to unfolding and exhibited reduced glycosylation activity against a complex array of glycosylation substrates and proteolytic processing of the transcription factor host cell factor 1, which is also encoded by an XLID-associated gene. We conclude that defects in O-GlcNAc homeostasis and host cell factor 1 proteolysis may play roles in mediation of XLID in individuals with OGT mutations.
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Deficiência Intelectual/genética , Mutação , N-Acetilglucosaminiltransferases/genética , Células Cultivadas , Criança , Pré-Escolar , Clonagem Molecular , DNA/genética , DNA/metabolismo , Humanos , Deficiência Intelectual/metabolismo , Masculino , N-Acetilglucosaminiltransferases/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMO
The gray platelet syndrome is a hereditary, usually autosomal recessive bleeding disorder caused by a deficiency of alpha granules in platelets. We detected a nonsense mutation in the gene encoding the transcription factor GFI1B (growth factor independent 1B) that causes autosomal dominant gray platelet syndrome. Both gray platelets and megakaryocytes had abnormal marker expression. In addition, the megakaryocytes had dysplastic features, and they were abnormally distributed in the bone marrow. The GFI1B mutant protein inhibited nonmutant GFI1B transcriptional activity in a dominant-negative manner. Our studies show that GFI1B, in addition to being causally related to the gray platelet syndrome, is key to megakaryocyte and platelet development.
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Plaquetas/patologia , Síndrome da Plaqueta Cinza/genética , Megacariócitos/patologia , Mutação , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Medula Óssea/patologia , Feminino , Genes Dominantes , Síndrome da Plaqueta Cinza/patologia , Humanos , Masculino , Linhagem , Células-Tronco , Trombocitopenia/genéticaRESUMO
Our case report documents the first type A aortic dissection in a patient with Kabuki syndrome (KS) and emphasize the need for intensive cardiovascular risk monitoring in patients with KS. It stresses the importance of further research to establish a correlation and awareness for patients with KS.
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BACKGROUND: Current guidelines indicate that patients with extreme oligozoospermia or azoospermia should be tested for chromosomal imbalances, azoospermia factor (AZF) deletions and/or CFTR variants. For other sperm abnormalities, no genetic diagnostics are recommended. OBJECTIVES: To determine whether exome sequencing (ES) with combined copy number variant (CNV) and single nucleotide variant (SNV) analysis is a reliable first-tier method to replace current methods (validation study), and to evaluate the diagnostic yield after 10 months of implementation (evaluation study). MATERIALS AND METHODS: In the validation study, ES was performed on DNA of patients already diagnosed with AZF deletions (n = 17), (non-)mosaic sex chromosomal aneuploidies or structural chromosomal anomalies (n = 37), CFTR variants (n = 26), or variants in known infertility genes (n = 4), and 90 controls. The data were analyzed using our standard diagnostic pipeline, with a bioinformatic filter for 130 male infertility genes. In the evaluation study, results of 292 clinical exomes were included. RESULTS: All previously reported variants in the validation cohort, including clinically relevant Y-chromosomal microdeletions, were correctly identified and reliably detected. In the evaluation study, we identified one or more clinically relevant genetic anomalies in 67 of 292 of all cases (22.9%): these included aberrations that could have been detected with current methods in 30 of 67 patients (10.2% of total), (possible) (mono)genetic causes in the male infertility gene panel in 28 of 67 patients (9.6%), and carriership of cystic fibrosis in nine of 67 patients (3.1%). CONCLUSION: ES is a reliable first-tier method to detect the most common genetic causes of male infertility and, as additional genetic causes can be detected, in our evaluation cohort the diagnostic yield almost doubled (10.2%-19.8%, excluding CF carriers). A genetic diagnosis provides answers on the cause of infertility and helps the professionals in the counseling for treatment, possible co-morbidities and risk for offspring and/or family members. Karyotyping will still remain necessary for detecting balanced translocations or low-grade chromosomal mosaicism.
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BACKGROUND: Vascular Ehlers-Danlos syndrome (vEDS) is a rare connective tissue disorder with a high risk for arterial, bowel, and uterine rupture, caused by heterozygous pathogenic variants in COL3A1. The aim of this cohort study is to provide further insights into the natural history of vEDS and describe genotype-phenotype correlations in a Dutch multicenter cohort to optimize patient care and increase awareness of the disease. METHODS: Individuals with vEDS throughout the Netherlands were included. The phenotype was charted by retrospective analysis of molecular and clinical data, combined with a one-time physical examination. RESULTS: A total of 142 individuals (50% female) participated the study, including 46 index patients (32%). The overall median age at genetic diagnosis was 41.0 years. More than half of the index patients (54.3%) and relatives (53.1%) had a physical appearance highly suggestive of vEDS. In these individuals, major events were not more frequent (P=0.90), but occurred at a younger age (P=0.01). A major event occurred more often and at a younger age in men compared with women (P<0.001 and P=0.004, respectively). Aortic aneurysms (P=0.003) and pneumothoraces (P=0.029) were more frequent in men. Aortic dissection was more frequent in individuals with a COL3A1 variant in the first quarter of the collagen helical domain (P=0.03). CONCLUSIONS: Male sex, type and location of the COL3A1 variant, and physical appearance highly suggestive of vEDS are risk factors for the occurrence and early age of onset of major events. This national multicenter cohort study of Dutch individuals with vEDS provides a valuable basis for improving guidelines for the diagnosing, follow-up, and treatment of individuals with vEDS.
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Colágeno Tipo III , Síndrome de Ehlers-Danlos , Humanos , Síndrome de Ehlers-Danlos/genética , Síndrome de Ehlers-Danlos/epidemiologia , Feminino , Masculino , Países Baixos/epidemiologia , Adulto , Colágeno Tipo III/genética , Pessoa de Meia-Idade , Estudos Retrospectivos , Estudos de Coortes , Fenótipo , Adolescente , Estudos de Associação Genética , Adulto Jovem , Idoso , Síndrome de Ehlers-Danlos Tipo IVRESUMO
BACKGROUND: Lynch syndrome is caused by germline mutations in MSH2, MLH1, MSH6, and PMS2 mismatch-repair genes and leads to a high risk of colorectal and endometrial cancer. We previously showed that constitutional 3' end deletions of EPCAM can cause Lynch syndrome through epigenetic silencing of MSH2 in EPCAM-expressing tissues, resulting in tissue-specific MSH2 deficiency. We aim to establish the risk of cancer associated with such EPCAM deletions. METHODS: We obtained clinical data for 194 carriers of a 3' end EPCAM deletion from 41 families known to us at the Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands and compared cancer risk with data from a previously described cohort of 473 carriers from 91 families with mutations in MLH1, MSH2, MSH6, or a combined EPCAM-MSH2 deletion. FINDINGS: 93 of the 194 EPCAM deletion carriers were diagnosed with colorectal cancer; three of the 92 women with EPCAM deletions were diagnosed with endometrial cancer. Carriers of an EPCAM deletion had a 75% (95% CI 65-85) cumulative risk of colorectal cancer before the age of 70 years (mean age at diagnosis 43 years [SD 12]), which did not differ significantly from that of carriers of combined EPCAM-MSH2 deletion (69% [95% CI 47-91], p=0·8609) or mutations in MSH2 (77% [64-90], p=0·5892) or MLH1 (79% [68-90], p=0·5492), but was higher than noted for carriers of MSH6 mutation (50% [38-62], p<0·0001). By contrast, women with EPCAM deletions had a 12% [0-27] cumulative risk of endometrial cancer, which was lower than was that noted for carriers of a combined EPCAM-MSH2 deletion (55% [20-90], p<0·0001) or of a mutation in MSH2 (51% [33-69], p=0·0006) or MSH6 (34% [20-48], p=0·0309), but did not differ significantly from that noted for MLH1 (33% [15-51], p=0·1193) mutation carriers. This risk seems to be restricted to deletions that extend close to the MSH2 gene promoter. Of 194 carriers of an EPCAM deletion, three had duodenal cancer and four had pancreatic cancer. INTERPRETATION: EPCAM deletion carriers have a high risk of colorectal cancer; only those with deletions extending close to the MSH2 promoter have an increased risk of endometrial cancer. These results underscore the effect of mosaic MSH2 deficiency, leading to variable cancer risks, and could form the basis of an optimised protocol for the recognition and targeted prevention of cancer in EPCAM deletion carriers.
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Antígenos de Neoplasias/genética , Moléculas de Adesão Celular/genética , Neoplasias Colorretais/genética , Neoplasias do Endométrio/genética , Deleção de Sequência , Adolescente , Adulto , Idoso , Estudos de Coortes , Neoplasias Colorretais/etiologia , Neoplasias do Endométrio/etiologia , Molécula de Adesão da Célula Epitelial , Feminino , Deleção de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 2 Homóloga a MutS/genética , Regiões Promotoras Genéticas , RiscoRESUMO
OBJECTIVES: To study the effects of antirheumatic drugs on hypothalamic-pituitary-adrenal (HPA) axis activity in patients with rheumatoid arthritis (RA). METHODS: Twenty patients with recent-onset active RA were studied before antirheumatic treatment, after 2 weeks of naproxen, and after 5½ months of additional treatment with sulphasalazine or methotrexate. The results before treatment were compared with those obtained in 20 age and sex-matched healthy controls (HC). Activity of the HPA-axis was assessed under basal conditions and during insulin tolerance tests (ITT). The ex-vivo production of interleukin (IL)-1ß, tumour necrosis factor-α (TNF-α) and IL-6 in whole blood samples was measured with and without stimulation by LPS. RESULTS: At baseline, plasma ACTH and cortisol levels were not different between patients with RA and HC. The unstimulated production of IL-6 was significantly higher in RA patients than in HC. After 2 weeks of treatment with naproxen, urinary cortisol excretion decreased significantly (p=0.03), and the area under the curve for plasma cortisol during the ITT was significantly lower (p=0.015). The LPS stimulated production of IL-1ß was significantly lower compared with baseline. After 6 months, basal plasma, salivary and urinary cortisol levels, and plasma cortisol and ACTH levels during the ITT, were all unchanged in comparison to the pre-treatment period. The unstimulated ex-vivo production of IL-1ß was significantly lower than before treatment. CONCLUSIONS: Our results suggest that the non-steroidal anti-inflammatory drug naproxen suppresses the HPA-axis in the first weeks of treatment. After 6 months, this suppressive effect is no longer present, suggesting the existence of adaptive mechanisms.
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Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Metotrexato/uso terapêutico , Naproxeno/uso terapêutico , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sulfassalazina/uso terapêutico , Hormônio Adrenocorticotrópico/sangue , Artrite Reumatoide/sangue , Artrite Reumatoide/fisiopatologia , Glicemia/análise , Citocinas/sangue , Quimioterapia Combinada , Feminino , Humanos , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/fisiologia , Insulina , Masculino , Sistema Hipófise-Suprarrenal/fisiologiaRESUMO
BACKGROUND: Computed tomography (CT), magnetic resonance imaging (MRI), and adrenal vein sampling (AVS) are used to distinguish unilateral from bilateral increased aldosterone secretion as a cause of primary aldosteronism. This distinction is crucial because unilateral primary aldosteronism can be treated surgically, whereas bilateral primary aldosteronism should be treated medically. PURPOSE: To determine the proportion of patients with primary aldosteronism whose CT or MRI results with regard to unilateral or bilateral adrenal abnormality agreed or did not agree with those of AVS. DATA SOURCES: PubMed, MEDLINE, EMBASE, and Cochrane Library, 1977 to April 2009. STUDY SELECTION: Studies describing adults with primary aldosteronism who underwent CT/MRI and AVS were included. Of 472 initially identified studies, 38 met the selection criteria; extractable data were available for 950 patients. DATA EXTRACTION: The CT/MRI result was considered accurate when AVS showed unilaterally increased aldosterone secretion on the same side as the abnormality seen on CT/MRI or when AVS showed symmetric aldosterone secretion and CT/MRI revealed bilateral or no unilateral abnormality. DATA SYNTHESIS: In 37.8% of patients (359 of 950), CT/MRI results did not agree with AVS results. If only CT/MRI results had been used to determine lateralization of an adrenal abnormality, inappropriate adrenalectomy would have occurred in 14.6% of patients (where AVS showed a bilateral problem), inappropriate exclusion from adrenalectomy would have occurred in 19.1% (where AVS showed unilateral secretion), and adrenalectomy on the wrong side would have occurred in 3.9% (where AVS showed aldosterone secretion on the opposite side). LIMITATION: The lack of follow-up data in the included articles made it impossible to confirm that adrenalectomies were performed appropriately. CONCLUSION: When AVS is used as the criterion standard test for diagnosing laterality of aldosterone secretion in patients with primary aldosteronism, CT/MRI misdiagnosed the cause of primary aldosteronism in 37.8% of patients. Relying only on CT/MRI may lead to inappropriate treatment of patients with primary aldosteronism.
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Aldosterona/metabolismo , Hiperaldosteronismo/diagnóstico , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Glândulas Suprarrenais/irrigação sanguínea , Aldosterona/sangue , Diagnóstico Diferencial , Feminino , Humanos , Hiperaldosteronismo/patologia , Masculino , Renina/sangue , Cloreto de Sódio , VeiasRESUMO
Several groups of investigators have reported an increased incidence of congenital anomalies in patients with congenital hypothyroidism. Furthermore, in patients with congenital hypothyroidism and mutations in genes known to be involved in thyroid development, specific extra-thyroidal abnormalities have been observed. The goal of the present study was to gain insight in the types and patterns of morphological characteristics depending on the type of congenital hypothyroidism of thyroidal origin (CH-T). In 242 Dutch CH-T patients with a thyroid agenesis, a dystopic thyroid rudiment or a eutopic thyroid gland, we performed a careful physical examination of the body surface directed to visually detectable morphological abnormalities; results were compared to a group of 1,007 Dutch control subjects. The percentage of patients with one or more major abnormalities in the total CH-T cohort (33.1%) and in patients with CH-T dystopic thyroid (37.2%) was significantly higher than in the control population (21.8%; P < 0.001). Especially in the CH-T dystopic thyroid group specific major malformations (bilateral ear pits; oligodontia) were found more frequently. Also, the percentage of patients in the total CH-T group with one or more minor anomalies (96.3%) was significantly higher than in the control group (82.5%). The careful grouping of patients according to their CH-T etiology and the types and patterns in morphological findings may be helpful in the search for novel genes involved in thyroid development.
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Anormalidades Congênitas/epidemiologia , Hipotireoidismo Congênito/complicações , Criança , Anormalidades Congênitas/etiologia , Feminino , Humanos , Lactente , Masculino , Países Baixos/epidemiologia , Prevalência , Adulto JovemRESUMO
AIM: To study the effect of the nonsteroidal anti-inflammatory drug naproxen on the activity of the hypothalamic-pituitary-adrenal (HPA) axis in healthy volunteers. METHODS: A double-blind, randomized study in two groups of 20 healthy volunteers was performed. The activity of the HPA axis was measured before and after the use of naproxen or placebo during a period of 2 weeks. Basal plasma adrenocorticotropic hormone (ACTH) and cortisol, 24-h urinary cortisol, and circadian cortisol rhythm in saliva were determined. Plasma ACTH and cortisol were also measured during submaximal physical exercise. RESULTS: There were no significant differences between the placebo and naproxen groups in basal plasma ACTH [09.00 h 3.1 pmol l(-1), 95% confidence interval (CI) 2.0, 4.2, and 2.8 pmol l(-1), 95% CI 1.9, 3.7, respectively], cortisol levels (09.00 h 0.45 micromol l(-1), 95% CI 0.39, 0.51, and 0.40 micromol l(-1), 95% CI 0.35, 0.44, respectively), 24 h urinary cortisol excretion (67.5 nmol 24 h(-1), 95% CI 54.3, 80.7, and 86.8 nmol 24 h(-1), 95% CI 54.4, 119.2, respectively), circadian cortisol rhythm measured in salivary samples, or ACTH and cortisol concentrations after physical exercise. After the use of placebo or naproxen for 2 weeks, no significant change in any of the parameters occurred (ACTH 09.00 h 3.0 pmol l(-1), 95% CI 2.0, 3.9, and 3.0 pmol l(-1), 95% CI 2.2, 3.8, respectively; cortisol 09.00 h 0.45 micromol l(-1), 95% CI 0.37, 0.52, and 0.39 micromol l(-1), 95% CI 0.34, 0.44, respectively; cortisol urine 79.5 nmol 24 h(-1), 95% CI 59.5, 99.4, and 81.7 nmol 24 h(-1), 95% CI 64.0, 99.4, respectively), and no significant differences were found in these parameters between the placebo and naproxen groups. CONCLUSIONS: The use of naproxen does not influence the activity of the HPA axis in healthy volunteers under basal circumstances or in response to physical stress.
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Hormônio Adrenocorticotrópico/sangue , Anti-Inflamatórios não Esteroides/farmacologia , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Naproxeno/farmacologia , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Adolescente , Adulto , Ritmo Circadiano , Método Duplo-Cego , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Saliva/química , Adulto JovemRESUMO
Context Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disease caused by mutations in the tumor suppressor gene MEN1 and can be diagnosed based on clinical, familial and/or genetic criteria. We present a family in which we found both germline and somatic mosaicism for MEN1. Family description In our proband, we diagnosed MEN1. The mutation was not detected in her parents (DNA extracted from leucocytes). When her brother was found to harbor the same MEN1 mutation as our proband and, around the same time, their father was diagnosed with a neuroendocrine carcinoma, this tumor was investigated for the MEN1 mutation as well. In the histologic biopsy of this tumor, the same MEN1 mutation was detected as previously found in his children. Re-analysis of his blood using multiplex ligation-dependent probe amplification (MLPA) showed a minimal, but consistently decreased signal for the MEN1-specific MLPA probes. The deletion was confirmed in his son by high-resolution array analysis. Based on the array data, we concluded that the deletion was limited to the MEN1 gene and that the father had both germline and somatic mosaicism for MEN1. Conclusions To our knowledge, this is the first reported family with combined germline and somatic mosaicism for MEN1. This study illustrates that germline mosaicism is important to consider in apparently sporadic de novo MEN1 mutations, because of its particular importance for genetic counseling, specifically when evaluating the risk for family members and when considering the possibility of somatic mosaicism in the parent with germline mosaicism.
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Mutação em Linhagem Germinativa , Mosaicismo , Neoplasia Endócrina Múltipla Tipo 1/genética , Adulto , Feminino , Humanos , Masculino , LinhagemRESUMO
CONTEXT: Central congenital hypothyroidism (CH-C) in neonates born to mothers with inadequately treated Graves' disease usually needs T(4) supplementation. The thyroid and its regulatory system have not yet been extensively studied after T(4) withdrawal, until we observed disintegrated thyroid glands in some patients. OBJECTIVE: The aim was to study the occurrence and pathogenesis of disintegrated thyroid glands in CH-C patients. DESIGN, SETTING, PATIENTS, PARTICIPANTS: Thyroid function was measured and thyroid ultrasound imaging was performed in 13 children with CH-C due to inadequately treated maternal Graves' disease after T(4)-supplementation withdrawal (group Aa). In addition, thyroid ultrasound imaging was performed in six children with CH-C born to inadequately treated mothers with Graves' disease, in whom T(4) supplementation was not withdrawn yet (group Ab) or never initiated (group Ac), in six euthyroid children born to adequately treated mothers with Graves' disease (group B), and in 10 T(4)-supplemented children with CH-C as part of multiple pituitary hormone deficiency (group C). MAIN OUTCOME MEASURES: Thyroid function and aspect (volume, echogenicity, echotexture) were measured. RESULTS: In group A, five children had developed thyroidal hypothyroidism characterized by persistently elevated TSH concentrations and exaggerated TSH responses after TRH stimulation. In the majority of patients in groups A and C, thyroid echogenicity and volume were decreased, and echotexture was inhomogeneous. Thyroid ultrasound imaging was normal in group B children. CONCLUSIONS: Inadequately treated maternal Graves' disease not only may lead to CH-C but also carries an, until now, unrecognized risk of thyroid disintegration in the offspring as well. We speculate that insufficient TSH secretion due to excessive maternal-fetal thyroid hormone transfer inhibits physiological growth and development of the child's thyroid.
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Hipotireoidismo Congênito/etiologia , Doença de Graves/complicações , Glândula Tireoide/patologia , Glândula Tireoide/fisiologia , Adulto , Criança , Pré-Escolar , Hipotireoidismo Congênito/diagnóstico por imagem , Hipotireoidismo Congênito/patologia , Feminino , Doença de Graves/tratamento farmacológico , Doença de Graves/patologia , Humanos , Lactente , Recém-Nascido , Troca Materno-Fetal , Hormônios Hipofisários/deficiência , Gravidez , Receptores da Tireotropina/sangue , Testes de Função Tireóidea , Glândula Tireoide/diagnóstico por imagem , Tireotropina/sangue , Tiroxina/uso terapêutico , UltrassonografiaRESUMO
CONTEXT: Patients with thyroidal congenital hypothyroidism (CH-T) born in The Netherlands in 1981-1982 showed persistent intellectual and motor deficits during childhood and adulthood, despite initiation of T(4) supplementation at a median age of 28 d after birth. OBJECTIVE: The present study examined whether advancement of treatment initiation to 20 d had resulted in improved cognitive and motor outcome. DESIGN/SETTING/PATIENTS: In 82 Dutch CH-T patients, born in 1992 to 1993 and treated at a median age of 20 d (mean, 22 d; range, 2-73 d), cognitive and motor outcome was assessed (mean age, 10.5 yr; range, 9.6-11.4 yr). Severity of CH-T was classified according to pretreatment free T(4) concentration. MAIN OUTCOME MEASURE: Cognitive and motor outcome of the 1992-1993 cohort in comparison to the 1981 to 1982 cohort was the main outcome measure. RESULTS: Patients with severe CH-T had lower full-scale (93.7), verbal (94.9), and performance (93.9) IQ scores than the normative population (P < 0.05), whereas IQ scores of patients with moderate and mild CH-T were comparable to those of the normative population. In all three severity subgroups, significant motor problems were observed, most pronounced in the severe CH-T group. No correlations were found between starting day of treatment and IQ or motor outcome. CONCLUSIONS: Essentially, findings from the 1992-1993 cohort were similar to those of the 1981-1982 cohort. Apparently, advancing initiation of T(4) supplementation from 28 to 20 d after birth did not result in improved cognitive or motor outcome in CH-T patients.
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Hipotireoidismo Congênito/complicações , Hipotireoidismo Congênito/diagnóstico , Inteligência , Destreza Motora , Triagem Neonatal , Criança , Estudos de Coortes , Hipotireoidismo Congênito/tratamento farmacológico , Feminino , Seguimentos , Humanos , Recém-Nascido , Masculino , Países Baixos , Tiroxina/uso terapêutico , Fatores de TempoRESUMO
BACKGROUND: Several genetic defects are associated with permanent congenital hypothyroidism. Immunologic, environmental, and iatrogenic (but not genetic) factors are known to induce transient congenital hypothyroidism, which spontaneously resolves within the first months of life. We hypothesized that molecular defects in the thyroid oxidase system, which is composed of at least two proteins, might be involved in the pathogenesis of permanent or transient congenital hypothyroidism in babies with defects in iodide organification, for which the oxidase system is required. METHODS: Nine patients were recruited who had idiopathic congenital hypothyroidism (one with permanent and eight with transient hypothyroidism) and an iodide-organification defect and who had been identified by the screening program for congenital hypothyroidism. The DNA of the patients and their relatives was analyzed for mutations in the genes for thyroid oxidase 1 (THOX1 ) and 2 (THOX2 ). RESULTS: The one patient with permanent and severe thyroid hormone deficiency and a complete iodide-organification defect had a homozygous nonsense mutation in the THOX2 gene that eliminates all functional domains of the protein. Three of the eight patients with mild transient congenital hypothyroidism and a partial iodide-organification defect had heterozygous mutations in the THOX2 gene that prematurely truncate the protein, thus abolishing its functional domains. CONCLUSIONS: Biallelic inactivating mutations in the THOX2 gene result in complete disruption of thyroid-hormone synthesis and are associated with severe and permanent congenital hypothyroidism. Monoallelic mutations are associated with milder, transient hypothyroidism caused by insufficient thyroidal production of hydrogen peroxide, which prevents the synthesis of sufficient quantities of thyroid hormones to meet the large requirement for thyroid hormones at the beginning of life.
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Hipotireoidismo Congênito , Flavoproteínas/genética , Hipotireoidismo/genética , Mutação , NADPH Oxidases , Análise Mutacional de DNA , Oxidases Duais , Feminino , Humanos , Peróxido de Hidrogênio/metabolismo , Recém-Nascido , Masculino , Linhagem , Hormônios Tireóideos/biossíntese , Hormônios Tireóideos/sangueRESUMO
OBJECTIVE AND DESIGN: Lowered neonatal plasma thyroxine (T(4)) and mildly elevated thyrotropin concentrations together with developmental benefits from neonatally started T(4) treatment in a randomized clinical trial demonstrated Down syndrome (DS) neonates to be mildly hypothyroid, at least during their first weeks of life. To prove that this hypothyroid state persists beyond this period in all, and to elucidate its etiology, we evaluated the course of the thyroid function determinants in all DS infants participating in this 24-month trial. MAIN OUTCOME: Mean plasma thyrotropin concentrations and thyrotropin frequency distributions of 97 placebo-treated infants were persistently shifted to substantially higher concentrations, while free T(4) frequency distributions were in the lower two thirds of the reference interval. Mean thyroglobulin concentrations were normal. To normalize plasma thyrotropin, T(4)-treated DS infants (N = 99) needed rather high free T(4) concentrations, like T(4)- treated non-DS children with thyroidal congenital hypothyroidism. At ages 12 and 24 months, thyroid peroxidase antibodies were detected in 1.1% and 5.4% of all DS infants. CONCLUSIONS: These findings suggest that as a group DS infants have a novel type of persistent mild congenital hypothyroidism, presumably of thyroidal origin. The group character suggests a direct relation with the trisomic state of chromosome 21, hypothetically through genomic dosage imbalance of dosage-sensitive genes interfering with thyroid hormone production.
Assuntos
Cromossomos Humanos Par 21 , Síndrome de Down/genética , Hipotireoidismo/genética , Glândula Tireoide/patologia , Trissomia , Pré-Escolar , Método Duplo-Cego , Síndrome de Down/complicações , Humanos , Lactente , Recém-Nascido , Iodeto Peroxidase/metabolismo , Placebos , Tireoglobulina/metabolismo , Tiroxina/sangue , Fatores de TempoRESUMO
Much worldwide attention is given to the adverse effects of maternal Graves' disease on the fetal and neonatal thyroid and its function. However, reports concerning the adverse effects of maternal Graves' disease on the pituitary function, illustrated by the development of central congenital hypothyroidism (CCH) in the offspring of these mothers, are scarce. We studied thyroid hormone determinants of 18 children with CCH born to mothers with Graves' disease. Nine mothers were diagnosed after pregnancy, the majority after their children were detected with CCH by neonatal screening. Four mothers were diagnosed during pregnancy and treated with antithyroid drugs since diagnosis. Another four mothers were diagnosed before pregnancy, but they used antithyroid drugs irregularly; free T(4) concentrations less than 1.7 ng/dl (<22 pmol/liter) were not encountered during pregnancy. All neonates had decreased plasma free T(4) concentrations (range 0.3-0.9 ng/dl, 3.9-11.5 pmol/liter); plasma TSH ranged between 0.1 and 6.6 mU/liter. TRH tests showed pituitary dysfunction. Seventeen children needed T(4) supplementation. Because all mothers were insufficiently treated during pregnancy, it is hypothesized that a hyperthyroid fetal environment impaired maturation of the fetal hypothalamic-pituitary-thyroid system. The frequent occurrence of this type of CCH (estimated incidence 1:35000) warrants early detection and treatment to minimize the risk of cerebral damage. A T(4)-based screening program appears useful in detecting this type of CCH. However, the preferential and presumably best strategy to prevent CCH caused by maternal Graves' disease is preserving euthyroidism throughout pregnancy.
Assuntos
Doença de Graves/complicações , Hipertireoidismo/congênito , Hipertireoidismo/etiologia , Complicações na Gravidez , Antitireóideos/uso terapêutico , Feminino , Sangue Fetal , Doença de Graves/tratamento farmacológico , Humanos , Hipertireoidismo/diagnóstico , Hipertireoidismo/tratamento farmacológico , Lactente , Recém-Nascido , Masculino , Triagem Neonatal , Gravidez , Complicações na Gravidez/tratamento farmacológico , Tireotropina/sangue , Hormônio Liberador de Tireotropina , Tiroxina/sangue , Tiroxina/uso terapêuticoRESUMO
OBJECTIVE: To describe the Dutch neonatal screening programme for congenital hypothyroidism (CH). DESIGN: Descriptive study. METHOD: Data on neonatal screening for CH in the period 1 January 1981 through 31 December 2011 were obtained from the Department for Vaccine Supply and Prevention Programmes of the Dutch National Institute for Public Health and the Environment (RIVM), laboratories and paediatricians to whom babies with abnormal screening results were referred. The screening procedure has been amended several times. In the period 1981-1994, only T4 and TSH were measured in heel prick blood, for example. From 1995, thyroxine-binding globulin (TBG) was added to the screening protocol. RESULTS: The participation rate was 99.7%. Before 1995 the sensitivity, specificity and positive predictive value were 94%, 99.51% and 6%, respectively. From 1995 these percentages were 98%, 99.85% and 21%, respectively. The total prevalence of CH was 1:2670 (prevalence of CH of thyroidal origin was 1:3100 and CH of central origin was 1:21,600). The percentages of patients with severe CH treated before day 15 in the periods 1981-1990, 1991-2000 and 2001-2011 were 24% (63/263), 63% (170/269) and 96% (176/184), respectively. CONCLUSION: The sensitivity and specificity of the screening procedure has considerably increased since 1995 compared with the period before 1995. In recent years patients with severe CH were treated considerably earlier than in the first years of the screening. Neonatal screening for CH may be considered as an important success for public health care.
Assuntos
Hipotireoidismo Congênito/diagnóstico , Triagem Neonatal/métodos , Hipotireoidismo Congênito/sangue , Feminino , Humanos , Recém-Nascido , Masculino , Triagem Neonatal/normas , Países Baixos/epidemiologia , Prevalência , Sensibilidade e Especificidade , Tireotropina/sangue , Tiroxina/sangue , Proteínas de Ligação a Tiroxina/análiseRESUMO
OBJECTIVE: The Dutch neonatal congenital hypothyroidism (CH) screening procedure and treatment modality has been adapted several times since its national institution in 1981. These changes enabled us to investigate whether earlier treatment has resulted in improved cognitive and motor outcomes. The present study examined whether the advancement of treatment modality has resulted in improved cognitive and motor outcomes. METHODS: In 95 toddlers with thyroidal CH (CH-T), born in 2002 through 2004 and treated at a median age of 9 days, cognitive and motor outcomes were assessed with the Bayley Scales of Infant Development-II-NL at 1 and 2 years of age. This outcome was also analyzed in relation to treatment variables. RESULTS: The mean mental developmental index (MDI) scores of the severe (initial free thyroxine [FT4] ≤0.4 ng/dL (≤5 pmol/L), moderate (0.4 < initial FT4 ≤ 0.8 ng/dL (5.0 < initial FT4 ≤ 10.0 pmol/L), and mild (initial FT4 > 0.8 ng/dL (>10.0 pmol/l) CH-T groups at 1 year and the moderate and mild CH-T groups at 2 years were similar to the population mean. The mean MDI scores of the total CH-T group and severe CH-T group at 2 years were significantly lower than the population mean (p < .0001). In all 3 severity subgroups, significant lower psychomotor developmental index scores (p < .0001) were observed. No correlations were found between starting day of treatment and developmental outcome. Initial T4 concentration and initial T4 dose were weak predictors for developmental outcome. CONCLUSION: Essentially, comparable with our earlier findings, children with CH, especially those with severe CH, are still at risk for motor and cognitive problems, which are probably due to the consequence of the prenatal hypothyroid state or the thyroid hormone deficiency in early life.
Assuntos
Desenvolvimento Infantil/fisiologia , Hipotireoidismo Congênito/fisiopatologia , Desenvolvimento Infantil/efeitos dos fármacos , Pré-Escolar , Hipotireoidismo Congênito/diagnóstico , Hipotireoidismo Congênito/tratamento farmacológico , Hipotireoidismo Congênito/psicologia , Feminino , Humanos , Lactente , Recém-Nascido , Inteligência , Masculino , Triagem Neonatal , Países Baixos , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia , Tiroxina/uso terapêutico , Resultado do TratamentoRESUMO
Loeys-Dietz syndrome (LDS) associates with a tissue signature for high transforming growth factor (TGF)-ß signaling but is often caused by heterozygous mutations in genes encoding positive effectors of TGF-ß signaling, including either subunit of the TGF-ß receptor or SMAD3, thereby engendering controversy regarding the mechanism of disease. Here, we report heterozygous mutations or deletions in the gene encoding the TGF-ß2 ligand for a phenotype within the LDS spectrum and show upregulation of TGF-ß signaling in aortic tissue from affected individuals. Furthermore, haploinsufficient Tgfb2(+/-) mice have aortic root aneurysm and biochemical evidence of increased canonical and noncanonical TGF-ß signaling. Mice that harbor both a mutant Marfan syndrome (MFS) allele (Fbn1(C1039G/+)) and Tgfb2 haploinsufficiency show increased TGF-ß signaling and phenotypic worsening in association with normalization of TGF-ß2 expression and high expression of TGF-ß1. Taken together, these data support the hypothesis that compensatory autocrine and/or paracrine events contribute to the pathogenesis of TGF-ß-mediated vasculopathies.