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1.
Nat Rev Endocrinol ; 20(5): 278-289, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38336897

RESUMO

Tumours of the anterior part of the pituitary gland represent just 1% of all childhood (aged <15 years) intracranial neoplasms, yet they can confer high morbidity and little evidence and guidance is in place for their management. Between 2014 and 2022, a multidisciplinary expert group systematically developed the first comprehensive clinical practice consensus guideline for children and young people under the age 19 years (hereafter referred to as CYP) presenting with a suspected pituitary adenoma to inform specialist care and improve health outcomes. Through robust literature searches and a Delphi consensus exercise with an international Delphi consensus panel of experts, the available scientific evidence and expert opinions were consolidated into 74 recommendations. Part 1 of this consensus guideline includes 17 pragmatic management recommendations related to clinical care, neuroimaging, visual assessment, histopathology, genetics, pituitary surgery and radiotherapy. While in many aspects the care for CYP is similar to that of adults, key differences exist, particularly in aetiology and presentation. CYP with suspected pituitary adenomas require careful clinical examination, appropriate hormonal work-up, dedicated pituitary imaging and visual assessment. Consideration should be given to the potential for syndromic disease and genetic assessment. Multidisciplinary discussion at both the local and national levels can be key for management. Surgery should be performed in specialist centres. The collection of outcome data on novel modalities of medical treatment, surgical intervention and radiotherapy is essential for optimal future treatment.


Assuntos
Adenoma , Neoplasias Hipofisárias , Adulto , Criança , Humanos , Adolescente , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/terapia , Adenoma/diagnóstico , Adenoma/epidemiologia , Adenoma/terapia , Hipófise , Consenso , Neuroimagem
2.
Nat Rev Endocrinol ; 20(5): 290-309, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38336898

RESUMO

Pituitary adenomas are rare in children and young people under the age of 19 (hereafter referred to as CYP) but they pose some different diagnostic and management challenges in this age group than in adults. These rare neoplasms can disrupt maturational, visual, intellectual and developmental processes and, in CYP, they tend to have more occult presentation, aggressive behaviour and are more likely to have a genetic basis than in adults. Through standardized AGREE II methodology, literature review and Delphi consensus, a multidisciplinary expert group developed 74 pragmatic management recommendations aimed at optimizing care for CYP in the first-ever comprehensive consensus guideline to cover the care of CYP with pituitary adenoma. Part 2 of this consensus guideline details 57 recommendations for paediatric patients with prolactinomas, Cushing disease, growth hormone excess causing gigantism and acromegaly, clinically non-functioning adenomas, and the rare TSHomas. Compared with adult patients with pituitary adenomas, we highlight that, in the CYP group, there is a greater proportion of functioning tumours, including macroprolactinomas, greater likelihood of underlying genetic disease, more corticotrophinomas in boys aged under 10 years than in girls and difficulty of peri-pubertal diagnosis of growth hormone excess. Collaboration with pituitary specialists caring for adult patients, as part of commissioned and centralized multidisciplinary teams, is key for optimizing management, transition and lifelong care and facilitates the collection of health-related quality of survival outcomes of novel medical, surgical and radiotherapeutic treatments, which are currently largely missing.


Assuntos
Acromegalia , Adenoma , Neoplasias Hipofisárias , Prolactinoma , Adulto , Masculino , Feminino , Humanos , Adolescente , Criança , Idoso , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/terapia , Neoplasias Hipofisárias/patologia , Adenoma/diagnóstico , Adenoma/terapia , Prolactinoma/diagnóstico , Prolactinoma/cirurgia
3.
Am J Med Genet A ; 194(2): 383-388, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37850521

RESUMO

PLAGL1 is one of a group of imprinted genes, whose altered expression causes imprinting disorders impacting growth, development, metabolism, and behavior. PLAGL1 over-expression causes transient neonatal diabetes mellitus (TNDM type 1) and, based on murine models, under-expression would be expected to cause growth restriction. However, only some reported individuals with upd(6)mat have growth restriction, giving rise to uncertainty about the role of PLAGL1 in human growth. Here we report three individuals investigated for growth restriction, two with upd(6)mat and one with a mosaic deletion of the paternally-inherited allele of PLAGL1. These cases add to evidence of its involvement in pre- and early post-natal human growth.


Assuntos
Impressão Genômica , Dissomia Uniparental , Recém-Nascido , Humanos , Animais , Camundongos , Impressão Genômica/genética , Fatores de Transcrição/genética , Proteínas de Ciclo Celular/genética , Proteínas Supressoras de Tumor/genética
4.
World J Pediatr Surg ; 6(4): e000599, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37860275

RESUMO

Background: Complications are frequently reported after hypospadias repair and there is a need to understand the factors that influence their occurrence. Methods: Data from boys with hypospadias born between 2000 and 2020 were obtained from the International Disorders of Sex Development (I-DSD) Registry. Logistic regressions, fisher's exact tests and spearman's correlation tests were performed on the data to assess associations between clinical factors and complication rates. Results: Of the 551 eligible boys, data were available on 160 (29%). Within the cohort, the median (range) External Masculinization Score (EMS) was 6 (2, 9). All presented with one or more additional genital malformation and 61 (38%) presented with additional extragenital malformations. Disorders of androgen action, androgen synthesis and gonadal development were diagnosed in 28 (18%), 22 (14%) and 9 (6%) boys, respectively. The remaining 101 (62%) patients were diagnosed as having non-specific 46,XY Disorders of Sex Development. Eighty (50%) boys had evidence of abnormal biochemistry, and gene variants were identified in 42 (26%). Median age at first hypospadias surgery was 2 years (0, 9), and median length of follow-up was 5 years (0, 17). Postsurgical complications were noted in 102 (64%) boys. There were no significant associations with postsurgical complications. Conclusions: Boys with proximal hypospadias in the I-DSD Registry have high rates of additional comorbidities and a high risk of postoperative complications. No clinical factors were significantly associated with complication rates. High complication rates with no observable cause suggest the involvement of other factors which need investigation.

5.
J Public Health (Oxf) ; 45(3): 738-747, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-36585903

RESUMO

BACKGROUND: Observational studies relating maternal 25-hydroxyvitamin D status to timing and mode of delivery have reported inconsistent results. We assessed the effect of antenatal cholecalciferol supplementation on the incidence of preterm birth, delivery mode and post-partum haemorrhage (PPH). METHODS: MAVIDOS was a randomized, double-blind, placebo-controlled trial of 1000 IU/day cholecalciferol from 14 weeks' gestation until delivery. Gestational age, mode of delivery [categorized as spontaneous vaginal delivery (SVD), instrumental (including forceps and vacuum extraction) or Caesarean section] and PPH (>500 ml estimated blood loss) were determined from medical records. RESULTS: A total of 965 women participated in the study until delivery. Gestation at birth and incidence of preterm birth (cholecalciferol 5.7%, placebo 4.5%, P = 0.43) were similar between the two treatment groups. SVD (versus instrumental or Caesarean delivery) was more likely in women randomized to cholecalciferol [Relative Risk (RR) 1.13, 95% confidence interval (CI) 1.02,1.25] due to lower instrumental (RR 0.68, 95%CI 0.51,0.91) but similar risk of Caesarean delivery (RR 0.94, 95%CI 0.74,1.19). PPH was less common in women randomized to cholecalciferol [32.1% compared with placebo (38.1%, P = 0.054) overall], but similar when stratified by delivery mode. CONCLUSIONS: Antenatal cholecalciferol supplementation did not alter timing of birth or prevalence of preterm birth but demonstrated a possible effect on the likelihood of SVD.


Assuntos
Cesárea , Nascimento Prematuro , Gravidez , Feminino , Recém-Nascido , Humanos , Cesárea/efeitos adversos , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/prevenção & controle , Colecalciferol/uso terapêutico , Parto Obstétrico , Suplementos Nutricionais
6.
J Clin Endocrinol Metab ; 107(3): 743-754, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-34687316

RESUMO

CONTEXT: Remission rates in young people with Graves hyperthyroidism are less than 25% after 2 years of thionamide antithyroid drug (ATD). OBJECTIVE: We explored whether rituximab (RTX), a B-lymphocyte-depleting agent, would increase remission rates when administered with a short course of ATD. METHODS: This was an open-label, multicenter, single-arm, phase 2 trial in young people (ages, 12-20 years) with Graves hyperthyroidism. An A'Hern design was used to distinguish an encouraging remission rate (40%) from an unacceptable rate (20%). Participants presenting with Graves hyperthyroidism received 500 mg RTX and 12 months of ATD titrated according to thyroid function. ATDs were stopped after 12 months and primary outcome assessed at 24 months. Participants had relapsed at 24 months if thyrotropin was suppressed and free 3,5,3'-triiodothyronine was raised; they had received ATD between months 12 and 24; or they had thyroid surgery/radioiodine. RESULTS: A total of 27 participants were recruited and completed the trial with no serious side effects linked to treatment. Daily carbimazole dose at 12 months was less than 5 mg in 21 of 27 participants. Thirteen of 27 participants were in remission at 24 months (48%, 90% one-sided CI, 35%-100%); this exceeded the critical value (9) for the A'Hern design and provided evidence of a promising remission rate. B-lymphocyte count at 28 weeks, expressed as a percentage of baseline, was related to likelihood of remission. CONCLUSION: Adjuvant RTX, administered with a 12-month course of ATD, may increase the likelihood of remission in young people with Graves hyperthyroidism. A randomized trial of adjuvant RTX in young people with Graves hyperthyroidism is warranted.


Assuntos
Antitireóideos/uso terapêutico , Doença de Graves/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Propiltiouracila/uso terapêutico , Rituximab/uso terapêutico , Adolescente , Criança , Quimioterapia Combinada/métodos , Feminino , Doença de Graves/sangue , Doença de Graves/diagnóstico , Doença de Graves/imunologia , Humanos , Imunoglobulinas Estimuladoras da Glândula Tireoide/sangue , Imunoglobulinas Estimuladoras da Glândula Tireoide/imunologia , Masculino , Recidiva , Resultado do Tratamento , Adulto Jovem
7.
Nat Commun ; 12(1): 2028, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795686

RESUMO

Germline mutations in BRAF and other components of the MAPK pathway are associated with the congenital syndromes collectively known as RASopathies. Here, we report the association of Septo-Optic Dysplasia (SOD) including hypopituitarism and Cardio-Facio-Cutaneous (CFC) syndrome in patients harbouring mutations in BRAF. Phosphoproteomic analyses demonstrate that these genetic variants are gain-of-function mutations leading to activation of the MAPK pathway. Activation of the MAPK pathway by conditional expression of the BrafV600E/+ allele, or the knock-in BrafQ241R/+ allele (corresponding to the most frequent human CFC-causing mutation, BRAF p.Q257R), leads to abnormal cell lineage determination and terminal differentiation of hormone-producing cells, causing hypopituitarism. Expression of the BrafV600E/+ allele in embryonic pituitary progenitors leads to an increased expression of cell cycle inhibitors, cell growth arrest and apoptosis, but not tumour formation. Our findings show a critical role of BRAF in hypothalamo-pituitary-axis development both in mouse and human and implicate mutations found in RASopathies as a cause of endocrine deficiencies in humans.


Assuntos
Mutação com Ganho de Função , Hipopituitarismo/genética , Hipotálamo/metabolismo , Hipófise/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Criança , Pré-Escolar , Corticotrofos/citologia , Corticotrofos/metabolismo , Displasia Ectodérmica/genética , Fácies , Insuficiência de Crescimento/genética , Células HEK293 , Cardiopatias Congênitas/genética , Humanos , Lactente , Sistema de Sinalização das MAP Quinases/genética , Melanotrofos/citologia , Melanotrofos/metabolismo , Camundongos Knockout , Camundongos Transgênicos , Proteínas Proto-Oncogênicas B-raf/metabolismo , Sequenciamento do Exoma/métodos
8.
Eur J Endocrinol ; 184(6): 791-801, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33780351

RESUMO

OBJECTIVES: To determine trends in clinical practice for individuals with DSD requiring gonadectomy. DESIGN: Retrospective cohort study. METHODS: Information regarding age at gonadectomy according to diagnosis; reported sex; time of presentation to specialist centre; and location of centre from cases reported to the International DSD Registry and who were over 16 years old in January 2019. RESULTS: Data regarding gonadectomy were available in 668 (88%) individuals from 44 centres. Of these, 248 (37%) (median age (range) 24 (17, 75) years) were male and 420 (63%) (median age (range) 26 (16, 86) years) were female. Gonadectomy was reported from 36 centres in 351/668 cases (53%). Females were more likely to undergo gonadectomy (n = 311, P < 0.0001). The indication for gonadectomy was reported in 268 (76%). The most common indication was mitigation of tumour risk in 172 (64%). Variations in the practice of gonadectomy were observed; of the 351 cases from 36 centres, 17 (5%) at 9 centres had undergone gonadectomy before their first presentation to the specialist centre. Median age at gonadectomy of cases from high-income countries and low-/middle-income countries (LMIC) was 13.0 years (0.1, 68) years and 16.5 years (1, 28), respectively (P < 0.0001) with the likelihood of long-term retention of gonads being higher in LMIC countries. CONCLUSIONS: The likelihood of gonadectomy depends on the underlying diagnosis, sex of rearing and the geographical setting. Clinical benchmarks, which can be studied across all forms of DSD will allow a better understanding of the variation in the practice of gonadectomy.


Assuntos
Castração/estatística & dados numéricos , Transtornos do Desenvolvimento Sexual/diagnóstico , Transtornos do Desenvolvimento Sexual/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos do Desenvolvimento Sexual/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Adulto Jovem
9.
Calcif Tissue Int ; 106(1): 30-46, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31089772

RESUMO

Vitamin D has important roles in calcium metabolism and in the prevention of rickets and osteomalacia; low levels of 25-hydroxyvitamin D are common in the general population and amongst pregnant women. Whilst there is a wealth of observational evidence linking vitamin D deficiency to a wide range of disease outcomes, there are currently few high-quality randomised controlled trials to confirm any causal associations, although many are currently in progress. Furthermore, currently, the vast majority of published guidelines recommend standard supplemental vitamin D doses for children and pregnant women, yet there is increasing recognition that individual characteristics and genetic factors may influence the response to supplementation. As such, future research needs to concentrate on documenting definite beneficial clinical outcomes of vitamin D supplementation, and establishing personalised dosing schedules and demonstrating effective approaches to optimising initiation and adherence.


Assuntos
Complicações na Gravidez/prevenção & controle , Deficiência de Vitamina D/prevenção & controle , Vitamina D/metabolismo , Vitaminas/metabolismo , Cálcio da Dieta/administração & dosagem , Cálcio da Dieta/metabolismo , Suplementos Nutricionais , Feminino , Humanos , Gravidez , Vitamina D/administração & dosagem , Vitaminas/administração & dosagem
10.
J Pediatr Endocrinol Metab ; 32(4): 403-407, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30849047

RESUMO

Context Germ cell tumours (GCTs) secreting ß-human chorionic gonadotropin (ß-HCG) are a rare cause of gonadotropin-independent precocious puberty (GIPP). Case description A 5.7-year-old boy presented with GIPP. Investigations to elucidate the underlying cause revealed elevated serum ß-HCG. Ultrasound of the abdomen and testes, urine steroid profile, bone isotope scan, and sequencing of the luteinizing hormone receptor gene (LHCGR) were normal. Despite paired serum and cerebrospinal fluid ß-HCG measurement suggesting local (brain) ß-HCG production, repeated magnetic resonance imaging (MRI) of the brain as well as MRI of the mediastinum did not identify a tumour source of persistently elevated serum ß-HCG. Treatment with cyproterone acetate and spironolactone was unsuccessful. Increase in testicular volumes prompted the addition of a gonadotropin releasing hormone (GnRH) analogue. Due to progressing virilisation and skeletal maturation, treatment was changed to a combination of anastrozole and bicalutamide at the age of 7 years. One year later, serum ß-HCG and testosterone concentrations spontaneously normalised followed by reductions in the height velocity, skeletal maturation and virilisation. The proband achieved his genetic height potential. No medication side effects were observed. The patient subsequently presented with non-secreting pineal GCT at 14 years, 8½ years after his initial presentation with GIPP. Conclusions Our case highlights that GIPP with no definite underlying aetiology at diagnosis should be considered as a prodrome for GCTs, and regular radiological surveillance for earlier tumour identification is warranted. To the best of our knowledge, our case is the first reported case of the use of anastrozole and bicalutamide in the setting of idiopathic GIPP. The good height outcome in our case warrants the trial of anastrozole and bicalutamide in similar cases.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hormônio Liberador de Gonadotropina/metabolismo , Puberdade Precoce/patologia , Anastrozol/administração & dosagem , Anilidas/administração & dosagem , Encéfalo/metabolismo , Criança , Gonadotropina Coriônica Humana Subunidade beta/metabolismo , Humanos , Masculino , Nitrilas/administração & dosagem , Prognóstico , Puberdade Precoce/tratamento farmacológico , Puberdade Precoce/metabolismo , Compostos de Tosil/administração & dosagem
11.
Horm Res Paediatr ; 90(4): 236-246, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30336477

RESUMO

BACKGROUND: Complete and partial androgen insensitivity syndrome (CAIS, PAIS) are associated with an increased risk of gonadal germ cell cancer (GGCC). Recent guidelines recommend gonadectomy in women with CAIS in late adolescence. Nevertheless, many adult women prefer to retain their gonads. AIMS: This study aims to explore attitudes towards gonadectomy in AIS in centres around the world, estimate the proportion of adults with retained gonads and/or who developed GGCC, and explore reasons for declining gonadectomy. METHODS: A survey was performed among health care professionals who use the International DSD Registry (I-DSD). RESULTS: Data were provided from 22 centres in 16 countries on 166 women (CAIS) and 26 men (PAIS). In CAIS, gonadectomy was recommended in early adulthood in 67% of centres; 19/166 (11.4%) women refused gonadectomy. Among 142 women who had gonadectomy, evidence of germ cell neoplasm in situ (GCNIS), the precursor of GGCC, was reported in 2 (1.4%) out of 8 from whom pathology results were formally provided. Nine out of 26 men with PAIS (34.6%) had retained gonads; 11% of centres recommended routine gonadectomy in PAIS. CONCLUSION: Although development of GGCC seems rare, gonadectomy after puberty is broadly recommended in CAIS; in PAIS this is more variable. Overall, our data reflect the need for evidence-based guidelines regarding prophylactic gonadectomy in AIS.


Assuntos
Síndrome de Resistência a Andrógenos/patologia , Ovário/patologia , Sistema de Registros , Testículo/patologia , Adolescente , Adulto , Síndrome de Resistência a Andrógenos/cirurgia , Feminino , Humanos , Masculino , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/prevenção & controle , Orquiectomia , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/prevenção & controle , Ovariectomia , Ovário/cirurgia , Neoplasias Testiculares/patologia , Neoplasias Testiculares/prevenção & controle , Testículo/cirurgia
12.
Pediatr Blood Cancer ; 65(1)2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28843052

RESUMO

We report the case of a 14-year-old male with metastatic alveolar rhabdomyosarcoma, presenting with hypercalcaemia (3.89 mmol/l) and elevated parathyroid hormone (PTH) level (10.2 pmol/l). Imaging demonstrated extensive bony lytic damage, with "floating teeth" in the mandible. Normalisation of calcium levels and bony reformation of the mandible occurred following chemotherapy; PTH levels decreased initially but remained above normal levels. Imaging did not demonstrate any evidence of parathyroid abnormality. Tumour ectopic PTH secretion is a very rare cause of hypercalcaemia of malignancy in children. Hypercalcaemia with an elevated PTH, in the absence of parathyroid-related cause, should prompt investigation for underlying malignancy.


Assuntos
Perda do Osso Alveolar/sangue , Regulação Neoplásica da Expressão Gênica , Hipercalcemia/sangue , Hormônio Paratireóideo/biossíntese , Rabdomiossarcoma Alveolar/sangue , Adolescente , Humanos , Masculino
13.
J Clin Endocrinol Metab ; 102(11): 4163-4172, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28938420

RESUMO

Context: Hajdu-Cheney syndrome (HJCYS) is a rare, multisystem bone disease caused by heterozygous mutations in the NOTCH2 gene. Histomorphometric and bone ultrastructural analyses in children have not been reported and sparse evidence exists on response to bisphosphonate (BP) therapy. Objective: To investigate clinical and bone histomorphometric characteristics, bone matrix mineralization, and the response of bone geometry and density to BP therapy. Patients: Five children with HJCYS (three males) between 6.7 and 15.3 years of age. Interventions: Various BP regimens (pamidronate, zoledronic acid, and alendronate) were used for between 1 and 10 years. Main Outcome Measures: Pretreatment transiliac bone biopsy specimens and peripheral quantitative computed tomography results were available in four and three subjects, respectively. Bone histomorphometry and quantitative backscattered electron imaging were performed in two patients. The response to BP was monitored using dual-energy X-ray absorptiometry and peripheral quantitative computed tomography. Results: Three patients had previously unreported NOTCH2 mutations. Histomorphometry demonstrated increased bone resorption and osteoclast numbers, increased heterogeneity of mineralization, and immature, woven bone. Trabecular bone formation was normal or elevated. Radius cortical thickness and density and lumbar spine bone mineral density were reduced at baseline and increased in response to BP therapy, which was not sustained after therapy discontinuation. Conclusions: Increased bone resorption and low cortical thickness are consistent with the effect of activating NOTCH2 mutations, which stimulate osteoclastogenesis. The increase in lumbar spine bone density and radial cortical thickness and density by BP therapy provides evidence of beneficial treatment effects in children with HJCYS.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Difosfonatos/uso terapêutico , Síndrome de Hajdu-Cheney/tratamento farmacológico , Adolescente , Alendronato/uso terapêutico , Osso e Ossos/fisiologia , Calcificação Fisiológica/efeitos dos fármacos , Estudos de Casos e Controles , Criança , Feminino , Síndrome de Hajdu-Cheney/genética , Síndrome de Hajdu-Cheney/metabolismo , Síndrome de Hajdu-Cheney/fisiopatologia , Humanos , Imidazóis/uso terapêutico , Masculino , Mutação , Osteoclastos/efeitos dos fármacos , Osteoclastos/fisiologia , Receptor Notch2/genética , Ácido Zoledrônico
14.
Nat Genet ; 49(3): 457-464, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28092684

RESUMO

Deadenylases are best known for degrading the poly(A) tail during mRNA decay. The deadenylase family has expanded throughout evolution and, in mammals, consists of 12 Mg2+-dependent 3'-end RNases with substrate specificity that is mostly unknown. Pontocerebellar hypoplasia type 7 (PCH7) is a unique recessive syndrome characterized by neurodegeneration and ambiguous genitalia. We studied 12 human families with PCH7, uncovering biallelic, loss-of-function mutations in TOE1, which encodes an unconventional deadenylase. toe1-morphant zebrafish displayed midbrain and hindbrain degeneration, modeling PCH-like structural defects in vivo. Surprisingly, we found that TOE1 associated with small nuclear RNAs (snRNAs) incompletely processed spliceosomal. These pre-snRNAs contained 3' genome-encoded tails often followed by post-transcriptionally added adenosines. Human cells with reduced levels of TOE1 accumulated 3'-end-extended pre-snRNAs, and the immunoisolated TOE1 complex was sufficient for 3'-end maturation of snRNAs. Our findings identify the cause of a neurodegenerative syndrome linked to snRNA maturation and uncover a key factor involved in the processing of snRNA 3' ends.


Assuntos
Doenças Cerebelares/genética , Exonucleases/genética , Mutação/genética , Proteínas Nucleares/genética , RNA Nuclear Pequeno/genética , Alelos , Animais , Feminino , Humanos , Masculino , Camundongos , Doenças Neurodegenerativas/genética , RNA Mensageiro/genética , Spliceossomos/genética , Peixe-Zebra
15.
Nat Rev Endocrinol ; 13(2): 105-124, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27585961

RESUMO

This Consensus Statement summarizes recommendations for clinical diagnosis, investigation and management of patients with Silver-Russell syndrome (SRS), an imprinting disorder that causes prenatal and postnatal growth retardation. Considerable overlap exists between the care of individuals born small for gestational age and those with SRS. However, many specific management issues exist and evidence from controlled trials remains limited. SRS is primarily a clinical diagnosis; however, molecular testing enables confirmation of the clinical diagnosis and defines the subtype. A 'normal' result from a molecular test does not exclude the diagnosis of SRS. The management of children with SRS requires an experienced, multidisciplinary approach. Specific issues include growth failure, severe feeding difficulties, gastrointestinal problems, hypoglycaemia, body asymmetry, scoliosis, motor and speech delay and psychosocial challenges. An early emphasis on adequate nutritional status is important, with awareness that rapid postnatal weight gain might lead to subsequent increased risk of metabolic disorders. The benefits of treating patients with SRS with growth hormone include improved body composition, motor development and appetite, reduced risk of hypoglycaemia and increased height. Clinicians should be aware of possible premature adrenarche, fairly early and rapid central puberty and insulin resistance. Treatment with gonadotropin-releasing hormone analogues can delay progression of central puberty and preserve adult height potential. Long-term follow up is essential to determine the natural history and optimal management in adulthood.


Assuntos
Gerenciamento Clínico , Internacionalidade , Síndrome de Silver-Russell/diagnóstico , Síndrome de Silver-Russell/terapia , Hormônio Liberador de Gonadotropina/uso terapêutico , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Síndrome de Silver-Russell/metabolismo
16.
Am J Med Genet A ; 170(6): 1556-63, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26940150

RESUMO

Proteoglycans are components of the extracellular matrix with diverse biological functions. Defects in proteoglycan synthesis have been linked to several human diseases with common features of short stature, hypermobility, joint dislocations, and skeletal dysplasia. B4GALT7 encodes galactosyltransferase-I that catalyzes the addition of a galactose moiety to a xylosyl group in the tetrasaccharide linker of proteoglycans. Mutations in this gene have been associated with the rare progeroid form of Ehlers Danlos syndrome and in addition more recently found to underlie Larsen of Reunion Island syndrome. Nine individuals have been reported with a diagnosis of the progeroid form of Ehlers Danlos syndrome, four of whom have had molecular characterization showing homozygous or compound heterozygous mutations in B4GALT7. We report two newly described patients with compound heterozygous mutations in B4GALT7, and show that the six individuals with confirmed mutations do not have the progeroid features described in the original five patients with a clinical diagnosis of the progeroid form of Ehlers Danlos syndrome. We suggest that galactosyltransferase-I deficiency does not cause the progeroid form of Ehlers Danlos syndrome, but instead results in a clinically recognizable syndrome comprising short stature, joint hypermobility, radioulnar synostosis, and severe hypermetropia. This group of syndromic patients are on a phenotypic spectrum with individuals who have Larsen of Reunion Island syndrome, although the key features of osteopenia, fractures and hypermetropia have not been reported in patients from Reunion Island. © 2016 Wiley Periodicals, Inc.


Assuntos
Galactosiltransferases/genética , Estudos de Associação Genética , Mutação , Fenótipo , Substituição de Aminoácidos , Densidade Óssea , Códon , Ecocardiografia , Síndrome de Ehlers-Danlos/diagnóstico , Síndrome de Ehlers-Danlos/genética , Fácies , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Radiografia , Síndrome
17.
Endocr Dev ; 28: 101-118, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26138838

RESUMO

Hypercalcaemia is rare in children. In adulthood, the causes are most frequently malignancy and primary hyperparathyroidism. In children, however, the aetiologies are diverse and age specific, and many have an underlying genetic basis. Hypercalcaemia is a serious condition that frequently leads to end-organ damage. In order to provide the most appropriate treatment, a key part of the management pathway is to establish the correct diagnosis promptly. When considering a practical approach to hypercalcaemia in children, it is helpful to consider the causes of hypercalcaemia according to the accompanying levels of parathyroid hormone (PTH), indicating whether the causes are PTH dependent or PTH independent. This chapter reviews the recent advances in this area and presents a practical approach to the investigation and subsequent management of this condition.


Assuntos
Hipercalcemia/congênito , Hipercalcemia/diagnóstico , Hiperparatireoidismo/diagnóstico , Falência Renal Crônica/diagnóstico , Neoplasias das Paratireoides/diagnóstico , Conservadores da Densidade Óssea/uso terapêutico , Criança , Difosfonatos/uso terapêutico , Humanos , Hipercalcemia/complicações , Hipercalcemia/etiologia , Hipercalcemia/terapia , Hiperparatireoidismo/complicações , Hiperparatireoidismo/terapia , Falência Renal Crônica/complicações , Neoplasias/complicações , Neoplasias/diagnóstico , Osteocondrodisplasias/complicações , Osteocondrodisplasias/diagnóstico , Hormônio Paratireóideo/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo , Neoplasias das Paratireoides/complicações , Neoplasias das Paratireoides/terapia , Paratireoidectomia , Diálise Renal , Vitamina D/intoxicação , Vitaminas/intoxicação , Síndrome de Williams/complicações , Síndrome de Williams/diagnóstico
18.
Eur J Med Genet ; 56(2): 114-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23261959

RESUMO

Hepatoblastoma is a tumour of early childhood occurring in association with genetic syndromes including Beckwith-Wiedemann Syndrome (BWS) which results from dominance of paternally-inherited genes on chromosome 11p15. We report a child without clinical BWS, neonatally diagnosed with focal congenital hyperinsulinism resulting from a paternally-inherited recessively-acting mutation of ABCC8 and pancreatic paternal uniparental disomy (UPD) for chromosome 11p15, who subsequently developed hepatoblastoma. Genetic testing showed UPD 11p15 in the pancreas and liver but not systemically, allowing the expression of mutated ABCC8 in both tissues. Infants with large or multifocal forms of focal congenital hyperinsulinism may be at risk of BWS-like tumours due to mosaic UPD despite negative whole-blood and buccal DNA testing and tumour surveillance should be considered for this minority.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Cromossomos Humanos Par 11 , Hiperinsulinismo Congênito/genética , Hepatoblastoma/genética , Neoplasias Hepáticas/genética , Mosaicismo , Mutação , Canais de Potássio Corretores do Fluxo de Internalização/genética , Receptores de Droga/genética , Dissomia Uniparental , Hiperinsulinismo Congênito/complicações , Hiperinsulinismo Congênito/diagnóstico , Hepatoblastoma/diagnóstico , Humanos , Lactente , Neoplasias Hepáticas/diagnóstico , Masculino , Repetições de Microssatélites , Tomografia por Emissão de Pósitrons , Receptores de Sulfonilureias , Tomografia Computadorizada por Raios X
19.
J Pediatr Endocrinol Metab ; 24(9-10): 811-4, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22145482

RESUMO

Diabetes insipidus (DI) is rare in childhood and has a wide-ranging aetiology including the involvement of uncontrolled proliferation of dendritic cells in the hypothalamic-pituitary axis, characteristic of Langerhans cell histiocytosis (LCH). DI may manifest as a sequela of multisystem LCH disease involving skin, bone, liver, spleen and lymph nodes. In very rare cases patients diagnosed with LCH exhibit neurodegenerative changes, such as severe ataxia, tremor, dysarthria and intellectual impairment. We report a 2 1/2-year-old boy who presented initially with apparent idiopathic DI, developed anterior pituitary hormone deficiency and progressive neurological deterioration secondary to neurodegenerative LCH.


Assuntos
Diabetes Insípido/patologia , Histiocitose de Células de Langerhans/patologia , Doenças Neurodegenerativas/patologia , Pré-Escolar , Diabetes Insípido/imunologia , Progressão da Doença , Histiocitose de Células de Langerhans/imunologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Doenças Neurodegenerativas/imunologia
20.
Endocr Dev ; 16: 93-114, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19494663

RESUMO

Hypercalcaemia is a rarer problem in children than that of hypocalcaemia. However, when it does occur, it is a condition that requires proper diagnosis before correct treatment can be instituted. Problems may arise either because of excess PTH secretion, e.g. because of parathyroid tumour, or because of inactivating mutations of the calcium-sensing receptor or because some other factor, such as vitamin D or PTHrP, causes hypercalcaemia independently of PTH. In the latter instance, PTH secretion is suppressed. It is often useful to get a clue to the aetiology by examining the urine calcium concentration as this may guide one towards the correct diagnosis. Treatment is aimed at either removing the source of the excess PTH or whichever other factor is involved. In some cases treatment is not necessary as the hypercalcaemia remains asymptomatic and does not cause any problems. If the underlying problem cannot be treated directly, measures can often be taken to reduce the plasma calcium by medical means which can sometimes be used as an interim measure before definitive treatment is undertaken.


Assuntos
Hipercalcemia/terapia , Cálcio/metabolismo , Criança , Granuloma/etiologia , Granuloma/terapia , Homeostase/fisiologia , Humanos , Hipercalcemia/etiologia , Hipercalcemia/metabolismo , Hipercalcemia/fisiopatologia , Hormônio Paratireóideo/sangue , Receptores de Detecção de Cálcio/genética
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