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OBJECTIVE: Adrenal cortisol production occurs through a biosynthetic pathway which depend on NADH and NADPH for energy supply. The mitochondrial respiratory chain and the reactive oxygen species (ROS) detoxification system are therefore important for steroidogenesis. Mitochondrial dysfunction leading to oxidative stress has been implicated in the pathogenesis of several adrenal conditions. Nonetheless, only very few patients with variants in one gene of the ROS detoxification system, Thioredoxin Reductase 2 (TXNRD2), have been described with variable phenotypes. DESIGN: Clinical, genetic, structural, and functional characterization of a novel, biallelic TXNRD2 splice variant. METHODS: On human biomaterial, we performed whole exome sequencing to identify and RNA analysis to characterize the specific TXNRD2 splice variant. Amino acid conservation analysis and protein structure modeling were performed in silico. Using patient's fibroblast-derived human induced pluripotent stem cells, we generated adrenal-like cells (iALC) to study the impact of wild-type (WT) and mutant TXNRD2 on adrenal steroidogenesis and ROS production. RESULTS: The patient had a complex phenotype of primary adrenal insufficiency (PAI), combined with genital, ophthalmological, and neurological features. He carried a homozygous splice variant c.1348-1G > T in TXNRD2 which leads to a shorter protein lacking the C-terminus and thereby affecting homodimerization and flavin adenine dinucleotide binding. Patient-derived iALC showed a loss of cortisol production with overall diminished adrenal steroidogenesis, while ROS production was significantly increased. CONCLUSION: Lack of TXNRD2 activity for mitochondrial ROS detoxification affects adrenal steroidogenesis and predominantly cortisol production.
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Tiorredoxina Redutase 2 , Humanos , Masculino , Tiorredoxina Redutase 2/genética , Tiorredoxina Redutase 2/metabolismo , Homozigoto , Espécies Reativas de Oxigênio/metabolismo , Hidrocortisona/metabolismo , Hidrocortisona/biossíntese , Células-Tronco Pluripotentes Induzidas/metabolismo , Sequenciamento do ExomaRESUMO
Biallelic loss-of-function variants in the IYD gene cause hypothyroidism resulting from iodine wasting. We describe 8 patients (from 4 families in which the parents are first cousins) who are homozygous for a variant in IYD (including a novel missense deleterious variant, c.791C>T [P264L], in 1 family). Seven patients presented between 5 and 16 years of age with a large goiter, overt hypothyroidism, and a high serum thyroglobulin. The goiter subsided with levothyroxine therapy in most. Upon stopping levothyroxine in 5 patients, goiter and hypothyroidism reappeared in 3. In these 3 patients, a rising serum thyroglobulin concentration preceded hypothyroidism and goiter and urinary iodine excretion was low. In patients who remained euthyroid, urinary iodine was normal. In conclusion, these patients bearing biallelic pathogenic variants in IYD developed a large goiter, a high serum thyroglobulin, and overt hypothyroidism when their iodine intake was low.
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Bócio , Hipotireoidismo , Linhagem , Tiroxina , Humanos , Feminino , Masculino , Adolescente , Hipotireoidismo/genética , Criança , Pré-Escolar , Tiroxina/uso terapêutico , Bócio/genética , Tireoglobulina/genética , Iodo/deficiência , Alelos , Mutação de Sentido Incorreto , SimportadoresRESUMO
Introduction: Craniopharyngiomas (CPs) are benign brain tumors accounting for 5 - 11% of intracranial tumors in children. These tumors often recur and can cause severe morbidity. Postoperative radiotherapy efficiently controls and prevents progression and recurrence. Despite advancements in neurosurgery, endocrinological, visual, and neuropsychological complications are common and significantly lower the quality of life of patients. Methods: We performed a retrospective study, including all patients younger than sixteen diagnosed with CP between July 1989 and August 2022 and followed up in Hôpital Universitaire de Bruxelles. Results: Nineteen children with CP were included, with median age of 7 years at first symptoms and 7.5 at diagnosis. Common symptoms at diagnosis were increased intracranial pressure (63%), visual impairment (47%), growth failure (26%), polyuria/polydipsia (16%), and weight gain (10.5%). As clinical signs at diagnosis, growth failure was observed in 11/18 patients, starting with a median lag of 1 year and 4 months before diagnosis. On ophthalmological examination, 27% of patients had papillary edema and 79% had visual impairment. When visual disturbances were found, the average preoperative volume was higher (p=0.039). Only 6/19 patients had gross total surgical resection. After the first neurosurgery, 83% experienced tumor recurrence or progression at a median time of 22 months. Eleven patients (73%) underwent postsurgical radiotherapy. At diagnosis, growth hormone deficiency (GHD) was the most frequent endocrine deficit (8/17) and one year post surgery, AVP deficiency was the most frequent deficit (14/17). Obesity was present in 13% of patients at diagnosis, and in 40% six months after surgery. There was no significant change in body mass index over time (p=0.273) after the first six months post-surgery. Conclusion: CP is a challenging brain tumor that requires multimodal therapy and lifelong multidisciplinary follow-up including hormonal substitution therapy. Early recognition of symptoms is crucial for prompt surgical management. The management of long-term sequelae and morbidity are crucial parts of the clinical path of the patients. The results of this study highlight the fundamental importance of carrying out a complete assessment (ophthalmological, endocrinological, neurocognitive) at the time of diagnosis and during follow-up so that patients can benefit from the best possible care.
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Craniofaringioma , Neoplasias Hipofisárias , Humanos , Craniofaringioma/cirurgia , Criança , Estudos Retrospectivos , Feminino , Masculino , Pré-Escolar , Adolescente , Neoplasias Hipofisárias/cirurgia , Neoplasias Hipofisárias/patologia , Seguimentos , Qualidade de VidaRESUMO
Objective: Until November 2019 in Belgium, dried blood spot (DBS) sampling was performed between 72 and 120 hours of life, when a majority of newborns had already been discharged from the maternity. In November 2019, the policy for newborn screening in South Belgium changed to allow sampling as soon as 48 hours of life, with the objective to accelerate the process and to allow more sampling during the hospital stay. Our objective was to evaluate the impact of this policy modification and, in particular, to assess the effectiveness of screening for hypothyroidism based on sampling before or after 72 hours of life, as well as to compare the effectiveness of DBS collection before discharge or at home. Methods: This retrospective study included live births ≥37 weeks of gestation, screened by the Université Libre de Bruxelles Newborn Screening Center between January 2019 and December 2021. To evaluate the efficiency of early sampling, we compared thyrotropin (TSH) results for screening <72 hours and screening ≥72 hours. We also compared TSH results of DBS performed before discharge with those performed at home. Results: A total of 53,794 newborns were included. The results of 24,816 healthy newborns screened before 72 hours of life and of 28,978 healthy newborns screened between 72 and 144 hours of life were compared. The median TSH level was similar (1.50 and 1.20 mU/L, respectively). The percentage of false positives was similar (0.08% and 0.07%, respectively). Earlier sampling, before 72 hours, allowed treatment of positive cases at 6 days rather than 8.5 days. DBS sampling at home resulted in longer delay for transferring the sample to the laboratory (a median of 3.0 days for hospital sampling vs. 5.0 days for home sampling). A poorer quality of home blood sampling was observed, with 0.27% unusable samples compared with 0.06% unusable samples for hospital sampling (p < 0.001). Conclusions: In term newborns, TSH screening before discharge, as early as 48 hours of life, is a valid strategy. It allows earlier treatment of positive cases, does not increase the percentage of false positives, and results in fewer unusable samples.
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Hipotireoidismo Congênito , Tireotropina , Gravidez , Humanos , Recém-Nascido , Feminino , Alta do Paciente , Estudos Retrospectivos , Triagem NeonatalRESUMO
Introduction: A substantial proportion of SGA patients present with a syndrome underlying their growth restriction. Most SGA cohorts comprise both syndromic and non-syndromic patients impeding delineation of the recombinant human growth hormone (rhGH) response. We present a detailed characterization of a SGA cohort and analyze rhGH response based on adult height (AH). Methods: Clinical and auxological data of SGA patients treated with rhGH, who had reached AH, were retrieved from BELGROW, a national database of all rhGH treated patients held by BESPEED (BElgian Society for PEdiatric Endocrinology and Diabetology). SGA patients were categorized in syndromic or non-syndromic patients. Results: 272 patients were included, 42 classified as syndromic (most frequent diagnosis (n=6): fetal alcohol syndrome and Silver-Russell syndrome). Compared with non-syndromic patients, syndromic were younger [years (median (P10/P90)] 7.43 (4.3/12.37) vs 10.21 (5.43/14.03), p=0.0005), shorter (height SDS -3.39 (-5.6/-2.62) vs -3.07 (-3.74/-2.62), p=0.0253) and thinner (BMI -1.70 (-3.67/0.04) vs -1.14 (-2.47/0.27) SDS, p=0.0054) at start of rhGH treatment. First year rhGH response was comparable (delta height SDS +0.54 (0.24/0.94) vs +0.56 (0.26/0.92), p=0.94). Growth pattern differed with syndromic patients having a higher prepubertal (SDS +1.26 vs +0.83, p=0.0048), but a lower pubertal height gain compared to the non-syndromic group (SDS -0.28 vs 0.44, p=0.0001). Mean rhGH dose was higher in syndromic SGA patients (mg/kg body weight/day 0.047 (0.039/0.064) vs 0.043 (0.035/0.056), p=0.0042). AH SDS was lower in syndromic SGA patients (-2.59 (-4.99/-1.57) vs -2.32 (-3.3/-1.2), p=0.0107). The majority in both groups remained short (<-2 SDS: syndromic 71%, non-syndromic 63%). Total height gain was comparable in both groups (delta height SDS +0.76 (-0.70/1.48) vs +0.86 (-0.12/1.86), p=0.41). Conclusions: Compared to non-syndromic SGA patients, syndromic SGA patients were shorter when starting rhGH therapy, started rhGH therapy earlier, and received a higher dose of rhGH. At AH, syndromic SGA patients were shorter than non-syndromic ones, but their height gain under rhGH therapy was comparable.
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Hormônio do Crescimento Humano , Doenças do Recém-Nascido , Recém-Nascido , Feminino , Adulto , Humanos , Criança , Hormônio do Crescimento , Hormônio do Crescimento Humano/uso terapêutico , Bélgica/epidemiologia , Idade Gestacional , Retardo do Crescimento Fetal/tratamento farmacológico , Proteínas Recombinantes , Doenças do Recém-Nascido/tratamento farmacológicoRESUMO
Objectives: To improve adult height in pubertal girls with a poor height prediction, treatment with growth hormone (GH) can be used in combination with a gonadotropin releasing hormone agonist (GnRHa), to delay closure of the growth plates. However, there are few studies to support this practice, and they show conflicting results. The objective of this trial is to assess the safety and efficacy of this combination treatment in early pubertal girls with a short predicted height, in comparison with matched controls. Design patients and methods: We designed an open-label, multicenter, interventional case-control study. Early pubertal girls with predicted adult height (PAH) below -2.5 SDS, were recruited in tertiary care centers in Belgium. They were treated for four years with GH and GnRHa. The girls were followed until adult height (AH) was reached. AH vs PAH, AH vs Height at start, and AH vs Target Height (TH) were evaluated, as well as safety parameters. Control data were assembled from historical patient files or from patients who preferred not to participate in the study. Results: Sixteen girls with mean age ( ± SD) at start of 11.0 years (± 1.3) completed the study protocol and follow-up. Their mean height ( ± SD) increased from 131.3 ± 4.1 cm (-2.3 ± 0.7 SDS) at start of treatment to 159.8 ± 4.7 cm (-1.1 ± 0.7 SDS) at AH. In matched controls, height increased from 132.3 ± 4.2 cm (-2.4 ± 0.5 SDS) to 153.2 ± 3.4 cm (-2.1 ± 0.6 SDS) (p<0.001). AH surpassed initial PAH by 12.0 ± 2.6 cm in treated girls; and by 4.2 ± 3.6 cm in the controls (p<0.001). Most treated girls reached normal adult height (>-2SD) (87.5%) and 68.7% reached or superseded the target height (TH), which was the case in only a minority of the controls (37.5% and 6.2%, respectively) (p= 0.003 and 0.001). A serious adverse event possibly related to the treatment, was a fracture of the metatarsals. Conclusion: A four-year GH/GnRHa treatment in early pubertal girls with a poor PAH seems safe and results in a clinically relevant and statistically significant increase in AH compared with matched historical controls. Clinical trial registration: ClinicalTrials.gov, identifier NCT00840944.
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Hormônio do Crescimento Humano , Puberdade Precoce , Feminino , Humanos , Adulto , Criança , Hormônio do Crescimento , Hormônio Liberador de Gonadotropina , Estudos de Casos e Controles , Estatura , Hormônio do Crescimento Humano/uso terapêutico , Puberdade Precoce/tratamento farmacológicoRESUMO
Context: Idiopathic central precocious puberty (iCPP) is defined by the premature reactivation of the hypothalamic-pituitary-gonadal axis with normal magnetic resonance imaging scan of the central nervous system, causing the development of secondary sexual characteristics before age 8 years in girls and 9 years in boys. MKRN3 loss of function variants now represent the most common genetic cause of iCPP. Objective: This work aims to document the clinical course of puberty in 8 families harboring pathogenic MKRN3 variants. Methods: This is an observational case series study of patients with CPP due to MKRN3 variants followed in a single center. Results: Genetic analysis of MKRN3 was carried out in 28 unrelated patients with iCPP and a family history of paternal inheritance or no/unavailable maternal inheritance, particularly in case of very early and rapidly evolving CPP. We identified 6 novel and 2 recently described variants in the MKRN3 gene in 9 girls, 1 boy, and their family members. These mutations were all predicted to be deleterious by in silico prediction programs. Conclusion: We have identified 6 novel MKRN3 mutations in children with CPP. An MKRN3 loss of function should be considered after careful history pinpointing paternally inherited CPP. A family segregation study allowed the detection of an MKRN3 variant in 2 young brothers still prepubertal, raising the question of screening and management of asymptomatic prepubertal family members.
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Objective: Experimental evidence suggests that the clinical manifestations of Triple A syndrome result from oxidative stress. Several conditions caused by oxidative stress display retinal involvement. Our objective was to assess the retina and optic nerve involvement in children with Triple A syndrome. Methods: Eleven patients with genetically proven Triple A syndrome followed-up in our centre were approached for study participation. The main outcome was the measurement of the thicknesses of the different retinal layers by Optical Coherence Tomography (OCT). Results: 9 patients with triple A syndrome had OCT measurements. 7 patients were children and 2 were adults; 4 were females and 5 were males. The 7 paediatric patients had at least two OCT measured at a mean interval of 7.9 months after the first one. The average Retinal Nerve Fibre Layer thickness was 74 ± 10 µm in patients compared to the paediatric reference range of 100 ± 2 µm (p<0.05). Conclusions and Relevance: This is the first study to document retinal layer thicknesses in a series of patients with Triple A syndrome. Nearly all retinal thickness and peripapillary RNFL measurements were very significantly inferior to the reference range in Triple A patients, whatever their age. RNFL thinning was more marked at the temporal part of the optic nerve. OCT being non-invasive, it represents a promising tool to assess the severity of neurodegeneration in patients with Triple A syndrome.
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Insuficiência Adrenal/complicações , Acalasia Esofágica/complicações , Doenças Neurodegenerativas/patologia , Retina/patologia , Tomografia de Coerência Óptica/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Doenças Neurodegenerativas/etiologia , Prognóstico , Estudos Retrospectivos , Adulto JovemRESUMO
OBJECTIVE: SRY-negative 46,XX testicular and ovotesticular disorders/differences of sex development (T/OTDSD) represent a very rare and unique DSD condition where testicular tissue develops in the absence of a Y chromosome. To date, very few studies have described the phenotype, clinical and surgical management and long-term outcomes of these patients. Particularly, early blockade of the gonadotropic axis in patients raised in the female gender to minimize postnatal androgenization has never been reported. DESIGN: Retrospective description of sixteen 46,XX T/OTDSD patients. RESULTS: Sixteen 46,XX SRY-negative T/OTDSD were included. Most (12/16) were diagnosed in the neonatal period. Sex of rearing was male for six patients and female for ten, while the clinical presentation varied, with an external masculinization score from 1 to 10. Five patients raised as girl were successfully treated with GnRH analog to avoid virilization during minipuberty. Ovotestes/testes were found bilaterally for 54% of the patients and unilaterally for the others (with a contralateral ovary). Gonadal surgery preserved appropriate tissue in the majority of cases. Spontaneous puberty occurred in two girls and one boy, while two boys required hormonal induction of puberty. One of the girls conceived spontaneously and had an uneventful pregnancy. DNA analyses (SNP-array, next-generation sequencing and whole-exome sequencing) were performed. A heterozygous frameshit mutation in the NR2F2 gene was identified in one patient. CONCLUSIONS: This study presents a population of patients with 46,XX SRY-negative T/OTDSD. Early blockade of gonadotropic axis appears efficient to reduce and avoid further androgenization in patients raised as girls.
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Transtornos Ovotesticulares do Desenvolvimento Sexual , Feminino , Humanos , Recém-Nascido , Masculino , Ovário , Transtornos Ovotesticulares do Desenvolvimento Sexual/genética , Estudos Retrospectivos , TestículoRESUMO
Ovotesticular disorder of sex development (OTD) management remains challenging. In OTD, cautious gonadal evaluation and separation of ovarian and testicular components might be required to avoid virilization of a patient with female identity. Herein we report our minimal invasive approach in this very rare condition. The gonads are externalized under laparoscopic control through trocar openings. Intraoperative ovotesticular ultrasonography (US) is used for clear identification of ovarian and testicular tissue which can then be safely separated. We strongly promote the use of a minimal invasive approach in the management of these patients undergoing long term treatment and often multiple procedures.
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Transtornos do Desenvolvimento Sexual , Transtornos Ovotesticulares do Desenvolvimento Sexual , Transtornos do Desenvolvimento Sexual/cirurgia , Feminino , Gônadas , Humanos , Ovário , Desenvolvimento SexualRESUMO
Objectives Congenital hypogonadotropic hypogonadism (CHH) is a rare condition resulting from GnRH deficiency. Gonadotropin Releasing Hormone 1 (GNRH1) homozygous mutations are an extremely rare cause of normosmic CHH (nCHH). Most heterozygous individuals are asymptomatic, with the notable exception of individuals heterozygous for a p.R31C GNRH1 mutation. Case presentation The patient is an index case from a consanguineous family, presenting with severe CHH and his parents presenting with late puberty and normal fertility. The index case is homozygous for a p.R31H GNRH1 variant, both parents being heterozygous. The analysis of a panel of genes implicated in CHH does not show any other clinically relevant variant in any other gene tested. Conclusions GNRH1 mutations are a rare cause of nCHH. Five different mutations have been reported so far in homozygous individuals. Most are frameshift in nature but the one reported here causes an amino acid change in the Gonadotropin-releasing hormone (GnRH) decapeptide. Both independently reported patients with the p.R31H mutation are from Turkish origin. The question of the possible role of this mutation in the late puberty of the heterozygous parents needs further documentation. An analogy is made with the heterozygous individuals carrying the p.R31C and displaying partial CHH. No nonreproductive disorder is noted.
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Hormônio Liberador de Gonadotropina/genética , Homozigoto , Hipogonadismo/genética , Mutação , Precursores de Proteínas/genética , Puberdade Tardia/genética , Adolescente , Adulto , Feminino , Heterozigoto , Humanos , Hipogonadismo/congênito , Hipogonadismo/patologia , Lactente , Masculino , Prognóstico , Adulto JovemRESUMO
The clinical presentation of combined pituitary hormone deficiency (CPHD) is variable. Some patients present with hypoglycemia during the neonatal period or during the first few years of life. Others present later in childhood with growth failure. We report on 7 patients with very late diagnosed severe hypopituitarism with pituitary stalk interruption syndrome. Five out of the 7 patients had recently migrated to Belgium and the 2 other patients were from low socio-economic status families. All of them presented to our clinic for short stature and some also complained of lack of pubertal development. Four out of the 7 patients reached final height which was within their target height, despite very delayed treatment.Conclusion: We illustrate the overall good outcome of these children with delayed diagnosed severe hypopituitarism. Adverse life conditions and social deprivation are thought to be the cause of their late diagnosis. In the current global socio-politic context, pediatricians in high-income countries should stay aware that migration and poor socio-economic status can be associated with specific clinical presentations.What is Known:⢠The clinical presentation of combined pituitary hormone deficiency (CPHD) is variable. Some patients present with hypoglycemia during the neonatal period or during the first few years of life. Others present later in childhood with growth failure.⢠A few case reports are published with very late diagnosis of congenital hypopituitarism.What is New:⢠We report on the largest series of delayed diagnosis of congenital hypopituitarism and illustrate the survival of these children with overall good prognosis.⢠Migration and social deprivation are thought to be the main cause of this late diagnosis.
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Diagnóstico Tardio/economia , Emigrantes e Imigrantes , Hipopituitarismo/diagnóstico , Pobreza , Classe Social , Adolescente , Adulto , Bélgica , Criança , Feminino , Seguimentos , Humanos , Hipopituitarismo/economia , Hipopituitarismo/etnologia , Masculino , Estudos Retrospectivos , Índice de Gravidade de Doença , Adulto JovemRESUMO
BACKGROUND: The type 1 insulin-like growth factor receptor (IGF1R) is a keystone of fetal growth regulation by mediating the effects of IGF-I and IGF-II. Recently, a cohort of patients carrying an IGF1R defect was described, from which a clinical score was established for diagnosis. We assessed this score in a large cohort of patients with identified IGF1R defects, as no external validation was available. Furthermore, we aimed to develop a functional test to allow the classification of variants of unknown significance (VUS) in vitro. METHODS: DNA was tested for either deletions or single nucleotide variant (SNV) and the phosphorylation of downstream pathways studied after stimulation with IGF-I by western blot analysis of fibroblast of nine patients. RESULTS: We detected 21 IGF1R defects in 35 patients, including 8 deletions and 10 heterozygous, 1 homozygous and 1 compound-heterozygous SNVs. The main clinical characteristics of these patients were being born small for gestational age (90.9%), short stature (88.2%) and microcephaly (74.1%). Feeding difficulties and varying degrees of developmental delay were highly prevalent (54.5%). There were no differences in phenotypes between patients with deletions and SNVs of IGF1R. Functional studies showed that the SNVs tested were associated with decreased AKT phosphorylation. CONCLUSION: We report eight new pathogenic variants of IGF1R and an original case with a homozygous SNV. We found the recently proposed clinical score to be accurate for the diagnosis of IGF1R defects with a sensitivity of 95.2%. We developed an efficient functional test to assess the pathogenicity of SNVs, which is useful, especially for VUS.
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Anormalidades Múltiplas/genética , Desenvolvimento Fetal/genética , Retardo do Crescimento Fetal/genética , Transtornos do Crescimento/genética , Receptor IGF Tipo 1/genética , Anormalidades Múltiplas/epidemiologia , Anormalidades Múltiplas/fisiopatologia , Adolescente , Criança , Nanismo/genética , Nanismo/fisiopatologia , Feminino , Retardo do Crescimento Fetal/epidemiologia , Retardo do Crescimento Fetal/fisiopatologia , Transtornos do Crescimento/epidemiologia , Transtornos do Crescimento/fisiopatologia , Heterozigoto , Homozigoto , Humanos , Recém-Nascido Pequeno para a Idade Gestacional/crescimento & desenvolvimento , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like II/genética , Masculino , Microcefalia/genética , Microcefalia/fisiopatologia , Mutação de Sentido Incorreto/genética , Linhagem , Polimorfismo de Nucleotídeo Único/genética , Receptores de Somatomedina/genéticaRESUMO
Isolated growth hormone deficiency (IGHD) is a rare condition mainly caused by mutations in GH1. The aim of this study was to assess the contribution of GHRHR mutations to IGHD in an unusually large group of patients. All GHRHR coding exons and flanking intronic regions were sequenced in 312 unrelated patients with nonsyndromic IGHD. Functional consequences of all newly identified missense variants were assessed in vitro (i.e., study of the expression of recombinant GHRHRs and their ability to activate the cyclic adenosine monophosphate (cAMP) signaling pathway). Genotype-phenotype correlation analyses were performed according to the nature of the identified mutation. We identified 20 different disease-causing GHRHR mutations (truncating and missense loss-of-function mutations), among which 15 are novel, in 24 unrelated patients. Of note, about half (13/24) of those patients represent sporadic cases. The clinical phenotype of patients with at least one missense GHRHR mutation was found to be indistinguishable from that of patients with bi-allelic truncating mutations. This study, which unveils disease-causing GHRHR mutations in 8% (24/312) of IGHD cases, identifies GHRHR as the second IGHD gene most frequently involved after GH1. The finding that 8% of IGHD cases without GH1 mutations are explained by GHRHR molecular defects (including missense mutations), together with the high proportion of sporadic cases among those patients, has important implications for genetic counseling.
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Nanismo Hipofisário/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Mutação , Receptores de Neuropeptídeos/genética , Receptores de Hormônios Reguladores de Hormônio Hipofisário/genética , Alelos , Sequência de Aminoácidos , Substituição de Aminoácidos , AMP Cíclico , Análise Mutacional de DNA , Nanismo Hipofisário/diagnóstico , Feminino , Genótipo , Hormônio do Crescimento Humano/genética , Humanos , Masculino , Linhagem , Receptores de Neuropeptídeos/química , Receptores de Hormônios Reguladores de Hormônio Hipofisário/químicaRESUMO
CONTEXT: The transcription factor RAX is a paired-type homeoprotein that plays a critical role in eye and forebrain development of vertebrate species. RAX knockout mice have anophthalmia, cleft palate, and an abnormal hypothalamus and display perinatal lethality. In humans, homozygous or compound heterozygous RAX mutations have been reported to cause bilateral microphthalmia or anophthalmia without consistent associated features. Congenital hypopituitarism can be associated with various eye or craniofacial anomalies; however, the co-occurrence of congenital hypopituitarism, anophthalmia, cleft palate, and diabetes insipidus has been very rare. RESULTS: We report the case of a child with anophthalmia, congenital hypopituitarism, diabetes insipidus, and bilateral cleft lip and palate who had a homozygous frameshift truncating mutation c.266delC (p.Pro89Argfs*114) in exon 1 of the RAX gene. Rax knockout mice show loss of ventral forebrain structures, pituitary, and basosphenoid bone and palate and a misplaced anterior pituitary gland along the roof of the oral cavity. CONCLUSIONS: Our patient's phenotype was more severe than that reported in other patients. Although most of the previously reported patients with RAX mutations showed either a missense or some less severe mutation in at least one of their RAX alleles, our patient was homozygous for truncating mutations that would yield a severe, null protein phenotype. The severity of the genetic defect, the precise match between the knockout mouse and the patient's endocrine phenotypes, and the prominent roles of RAX in eye and pituitary development and diencephalic patterning suggest that the RAX null mutations could fully account for the observed phenotype.
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Anoftalmia/genética , Fenda Labial/genética , Fissura Palatina/genética , Diabetes Insípido/genética , Proteínas do Olho/genética , Proteínas de Homeodomínio/genética , Hipopituitarismo/genética , Fatores de Transcrição/genética , Animais , Anoftalmia/diagnóstico por imagem , Anoftalmia/patologia , Antidiuréticos/uso terapêutico , Fenda Labial/diagnóstico por imagem , Fenda Labial/patologia , Fissura Palatina/diagnóstico por imagem , Fissura Palatina/patologia , Desamino Arginina Vasopressina/uso terapêutico , Diabetes Insípido/diagnóstico por imagem , Diabetes Insípido/tratamento farmacológico , Diabetes Insípido/patologia , Mutação da Fase de Leitura , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Hidrocortisona/uso terapêutico , Hipopituitarismo/diagnóstico por imagem , Hipopituitarismo/tratamento farmacológico , Hipopituitarismo/patologia , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Melatonina , Camundongos Knockout , Hipófise/anormalidades , Tiroxina/uso terapêuticoRESUMO
Inherited retinal dystrophies (iRDs) are a group of genetically and clinically heterogeneous conditions resulting from mutations in over 250 genes. Here, homozygosity mapping and whole-exome sequencing (WES) in a consanguineous family revealed a homozygous missense mutation, c.973C>T (p.His325Tyr), in RCBTB1. In affected individuals, it was found to segregate with retinitis pigmentosa (RP), goiter, primary ovarian insufficiency, and mild intellectual disability. Subsequent analysis of WES data in different cohorts uncovered four additional homozygous missense mutations in five unrelated families in whom iRD segregates with or without syndromic features. Ocular phenotypes ranged from typical RP starting in the second decade to chorioretinal dystrophy with a later age of onset. The five missense mutations affect highly conserved residues either in the sixth repeat of the RCC1 domain or in the BTB1 domain. A founder haplotype was identified for mutation c.919G>A (p.Val307Met), occurring in two families of Mediterranean origin. We showed ubiquitous mRNA expression of RCBTB1 and demonstrated predominant RCBTB1 localization in human inner retina. RCBTB1 was very recently shown to be involved in ubiquitination, more specifically as a CUL3 substrate adaptor. Therefore, the effect on different components of the CUL3 and NFE2L2 (NRF2) pathway was assessed in affected individuals' lymphocytes, revealing decreased mRNA expression of NFE2L2 and several NFE2L2 target genes. In conclusion, our study puts forward mutations in RCBTB1 as a cause of autosomal-recessive non-syndromic and syndromic iRD. Finally, our data support a role for impaired ubiquitination in the pathogenetic mechanism of RCBTB1 mutations.
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Alelos , Fatores de Troca do Nucleotídeo Guanina/genética , Mutação de Sentido Incorreto/genética , Distrofias Retinianas/genética , Ubiquitinação/genética , Adolescente , Adulto , Idade de Início , Criança , Consanguinidade , Proteínas Culina/metabolismo , Exoma/genética , Feminino , Efeito Fundador , Genes Recessivos , Haplótipos/genética , Homozigoto , Humanos , Linfócitos/metabolismo , Masculino , Fator 2 Relacionado a NF-E2/metabolismo , Linhagem , Fenótipo , RNA Mensageiro/genética , Retina/metabolismo , Síndrome , TurquiaRESUMO
AIM: To assess the management and outcome of the congenital hypothyroidism (CH) patients followed at our institution since the introduction of systemic neonatal screening for CH. STUDY DESIGN: The records of 139 CH patients referred to our center between 1978 and 2014 were retrospectively reviewed. Biochemical and imaging data at diagnosis, initial treatment and growth were analyzed. RESULTS: 111 patients had thyroid dysgenesis (64 ectopy, 46 athyreosis and 1 hypoplasia) and 28 patients had a gland in situ (17 dyshormonogenesis/goiter and 11 normal-sized gland). Levothyroxine treatment was initiated at a median age of 11 days with a mean dose of 11.4 µg/kg/day. Compared to those with ectopy, patients with athyreosis had higher thyroid-stimulating hormone (TSH) and lower thyroxine at diagnosis as well as more delayed bone maturation. Between 1978 and 2014, we observed earlier treatment and earlier TSH normalization. Birth auxology was slightly above the mean of the reference population. Growth at 1 and 6 years and school progression at 11 years were similar to those of the reference population. CONCLUSION: Ectopy is the commonest cause of CH. Children with CH treated early with a mean levothyroxine dose of 11.4 µg/kg/day had a median TSH of 3.07 mU/l at 1 month of age and normal growth.
Assuntos
Hipotireoidismo Congênito/tratamento farmacológico , Tiroxina/administração & dosagem , Hipotireoidismo Congênito/diagnóstico , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Estudos RetrospectivosRESUMO
Ovarian insufficiency is a major long-term adverse event, following the administration of a myeloablative conditioning regimen, and occurring in >80% of children and adolescents receiving such treatment for malignant or non-malignant disease. Cryopreservation of ovarian tissue is currently offered to preserve the fertility of these young patients. At least 35 live births have been reported after transplantation of cryopreserved ovarian tissue in adult patients, but the procedure remains unproven for ovarian tissue harvested at a prepubertal or pubertal age. We report here the first live birth after autograft of cryopreserved ovarian tissue in a woman with primary ovarian failure after a myeloablative conditioning regimen as part of a hematopoietic stem cell transplantation performed for homozygous sickle-cell anemia at age 14 years. This first report of successful fertility restoration after the graft of ovarian tissue cryopreserved before menarche offers reassuring evidence for the feasibility of the procedure when performed during childhood.
Assuntos
Autoenxertos/transplante , Criopreservação , Preservação da Fertilidade/métodos , Nascido Vivo , Ovário/transplante , Adolescente , Adulto , Anemia Falciforme/terapia , Feminino , Humanos , Agonistas Mieloablativos/efeitos adversos , Gravidez , Insuficiência Ovariana Primária/induzido quimicamente , Transplante AutólogoRESUMO
BACKGROUND: Nephrogenic syndrome of inappropriate antidiuresis (NSIAD) is a rare X-linked disease due to gain-of-function mutations in the AVP V2 receptor gene. Hemizygous males present with recurrent episodes of severe hyponatremia in infancy. Heterozygous females are usually asymptomatic. CASE REPORT: We report on a 23-day-old female neonate, born at term with 3,260 g that presented with recurrent hyponatremia (Na between 124 and 134 mmol/l) due to NSIAD. She was a heterozygous carrier of the c.409 C>T mutation in the AVPR2 gene. CONCLUSIONS: This is the first report of a female neonate presenting with hyponatremia due to NSIAD. The diagnosis of NSIAD should not be limited to male infants and should also be considered in female infants with the clinical picture of inappropriate antidiuresis.
Assuntos
Doenças Genéticas Ligadas ao Cromossomo X , Heterozigoto , Hiponatremia , Síndrome de Secreção Inadequada de HAD , Receptores de Vasopressinas/genética , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/metabolismo , Humanos , Hiponatremia/diagnóstico , Hiponatremia/genética , Hiponatremia/metabolismo , Síndrome de Secreção Inadequada de HAD/diagnóstico , Síndrome de Secreção Inadequada de HAD/genética , Síndrome de Secreção Inadequada de HAD/metabolismo , Recém-NascidoRESUMO
Russell-Silver Syndrome (RSS) is a prenatal and postnatal growth retardation syndrome caused mainly by 11p15 ICR1 hypomethylation. Clinical presentation is heterogeneous in RSS patients with 11p15 ICR1 hypomethylation. We previously identified a subset of RSS patients with 11p15 ICR1 and multilocus hypomethylation. Here, we examine the relationships between IGF2 expression, 11p15 ICR1 methylation, and multilocus imprinting defects in various cell types from 39 RSS patients with 11p15 ICR1 hypomethylation in leukocyte DNA. 11p15 ICR1 hypomethylation was more pronounced in leukocytes than in buccal mucosa cells. Skin fibroblast IGF2 expression was correlated with the degree of ICR1 hypomethylation. Different tissue-specific multilocus methylation defects coexisted in 38% of cases, with some loci hypomethylated and others hypermethylated within the same cell type in some cases. Our new results suggest that tissue-specific epigenotypes may lead to clinical heterogeneity in RSS.