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1.
Am J Med Genet A ; 194(2): 243-252, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37814549

RESUMO

Hypochondroplasia (HCH) is a rare skeletal dysplasia causing mild short stature. There is a paucity of growth reference charts for this population. Anthropometric data were collected to generate height, weight, and head circumference (HC) growth reference charts for children with a diagnosis of HCH. Mixed longitudinal anthropometric data and genetic analysis results were collected from 14 European specialized skeletal dysplasia centers. Growth charts were generated using Generalized Additive Models for Location, Scale, and Shape. Measurements for height (983), weight (896), and HC (389) were collected from 188 (79 female) children with a diagnosis of HCH aged 0-18 years. Of the 84 children who underwent genetic testing, a pathogenic variant in FGFR3 was identified in 92% (77). The data were used to generate growth references for height, weight, and HC, plotted as charts with seven centiles from 2nd to 98th, for ages 0-4 and 0-16 years. HCH-specific growth charts are important in the clinical care of these children. They help to identify if other comorbidities are present that affect growth and development and serve as an important benchmark for any prospective interventional research studies and trials.


Assuntos
Osso e Ossos/anormalidades , Nanismo , Deformidades Congênitas dos Membros , Lordose , Osteocondrodisplasias , Criança , Humanos , Feminino , Gráficos de Crescimento , Estudos Prospectivos , Estatura/genética , Nanismo/diagnóstico , Nanismo/genética , Valores de Referência
2.
JCEM Case Rep ; 1(3): luad028, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37908565

RESUMO

X-linked acrogigantism (X-LAG) is characterized by extreme tall stature from early childhood resulting from duplication of the GPR101 gene, in turn resulting in GH excess. Most cases present with pituitary tumors secreting GH and prolactin. Diffuse pituitary hyperplasia is uncommon and normal prolactin is rare. We present a girl with tall stature from 3 years of age; her height was +4.25 SD score at 5 years, with no signs of syndromic disease. She had significant GH excess, serum IGF-1 4 times the upper limit of normal and normal circulating GHRH, with normal pituitary magnetic resonance imaging over 13 years. No abnormalities were found in either the AIP or MEN1 genes. Treatment with somatostatin analogues and dopamine agonists showed minimal therapeutic benefit, but significant side effects. She tested positive for duplication of GPR101 6 years after the initial diagnosis. She was then initiated on pegvisomant aged 12 years, achieving prompt IGF-1 normalization and growth cessation. Aged 16.5 years, she showed escape from IGF-1 control, and height velocity increased, but this responded well to a dose increase in pegvisomant, with reassuring long-term pediatric safety over 7 years. Her final height is +2.9 SD score. Currently, life-long pegvisomant treatment is planned with genetic counselling regarding future offspring.

3.
Genome Med ; 14(1): 79, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35883178

RESUMO

BACKGROUND: Genomic variants which disrupt splicing are a major cause of rare genetic diseases. However, variants which lie outside of the canonical splice sites are difficult to interpret clinically. Improving the clinical interpretation of non-canonical splicing variants offers a major opportunity to uplift diagnostic yields from whole genome sequencing data. METHODS: Here, we examine the landscape of splicing variants in whole-genome sequencing data from 38,688 individuals in the 100,000 Genomes Project and assess the contribution of non-canonical splicing variants to rare genetic diseases. We use a variant-level constraint metric (the mutability-adjusted proportion of singletons) to identify constrained functional variant classes near exon-intron junctions and at putative splicing branchpoints. To identify new diagnoses for individuals with unsolved rare diseases in the 100,000 Genomes Project, we identified individuals with de novo single-nucleotide variants near exon-intron boundaries and at putative splicing branchpoints in known disease genes. We identified candidate diagnostic variants through manual phenotype matching and confirmed new molecular diagnoses through clinical variant interpretation and functional RNA studies. RESULTS: We show that near-splice positions and splicing branchpoints are highly constrained by purifying selection and harbour potentially damaging non-coding variants which are amenable to systematic analysis in sequencing data. From 258 de novo splicing variants in known rare disease genes, we identify 35 new likely diagnoses in probands with an unsolved rare disease. To date, we have confirmed a new diagnosis for six individuals, including four in whom RNA studies were performed. CONCLUSIONS: Overall, we demonstrate the clinical value of examining non-canonical splicing variants in individuals with unsolved rare diseases.


Assuntos
Splicing de RNA , Doenças Raras , Éxons , Humanos , Íntrons , RNA , Doenças Raras/genética
4.
Int J Mol Sci ; 22(23)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34884497

RESUMO

Recently, we reported a case of an infant with neonatal severe under-mineralizing skeletal dysplasia caused by mutations within both alleles of the TRPV6 gene. One mutation results in an in frame stop codon (R510stop) that leads to a truncated, nonfunctional TRPV6 channel, and the second in a point mutation (G660R) that, surprisingly, does not affect the Ca2+ permeability of TRPV6. We mimicked the subunit composition of the unaffected heterozygous parent and child by coexpressing the TRPV6 G660R and R510stop mutants and combinations with wild type TRPV6. We show that both the G660R and R510stop mutant subunits are expressed and result in decreased calcium uptake, which is the result of the reduced abundancy of functional TRPV6 channels within the plasma membrane. We compared the proteomic profiles of a healthy placenta with that of the diseased infant and detected, exclusively in the latter two proteases, HTRA1 and cathepsin G. Our results implicate that the combination of the two mutant TRPV6 subunits, which are expressed in the placenta of the diseased child, is responsible for the decreased calcium uptake, which could explain the skeletal dysplasia. In addition, placental calcium deficiency also appears to be associated with an increase in the expression of proteases.


Assuntos
Canais de Cálcio/genética , Catepsina G/metabolismo , Serina Peptidase 1 de Requerimento de Alta Temperatura A/metabolismo , Mutação , Osteocondrodisplasias/patologia , Placenta/patologia , Proteoma/metabolismo , Canais de Cátion TRPV/genética , Sequência de Aminoácidos , Animais , Canais de Cálcio/metabolismo , Canais de Cálcio/fisiologia , Estudos de Casos e Controles , Catepsina G/genética , Feminino , Regulação Enzimológica da Expressão Gênica , Serina Peptidase 1 de Requerimento de Alta Temperatura A/genética , Humanos , Lactente , Camundongos Knockout , Osteocondrodisplasias/etiologia , Osteocondrodisplasias/metabolismo , Placenta/metabolismo , Gravidez , Proteoma/análise , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/fisiologia
5.
Am J Med Genet A ; 185(4): 1228-1235, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33439541

RESUMO

Spondylometaphyseal dysplasia with cerebral hypomyelination (SMD-H) is a very rare but distinctive phenotype, unusually combining spondylometaphyseal dysplasia with hypomyelinating leukodystrophy. Recently, SMD-H has been associated with variants confined to a specific intra-genic locus involving Exon 7, suggesting that AIFM1 plays an important role in bone development and metabolism as well as cerebral myelination. Here we describe two further affected boys, one with a novel intronic variant associated with skipping of Exon 7 of AIFM1 and the other a synonymous variant within Exon 7 of AIFM1. We describe their clinical course and radiological and genetic findings, providing further insight into the natural history of this condition.


Assuntos
Fator de Indução de Apoptose/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Predisposição Genética para Doença , Malformações do Sistema Nervoso/genética , Osteocondrodisplasias/genética , Desenvolvimento Ósseo/genética , Éxons , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico por imagem , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Humanos , Masculino , Mutação/genética , Malformações do Sistema Nervoso/diagnóstico , Malformações do Sistema Nervoso/diagnóstico por imagem , Malformações do Sistema Nervoso/patologia , Osteocondrodisplasias/diagnóstico , Osteocondrodisplasias/diagnóstico por imagem , Osteocondrodisplasias/patologia , Linhagem
6.
J Hum Genet ; 66(4): 371-377, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33037392

RESUMO

Dysosteosclerosis (DOS) is a distinct form of sclerosing bone disease characterized by platyspondyly and progressive osteosclerosis. DOS is genetically heterogeneous. Three causal genes, SLC29A3, CSF1R, and TNFRSF11A are reported. TNFRSF11A-associated DOS has been identified in two patients; however, TNFRSF11A is also a causal gene for osteopetrosis, autosomal recessive 7 (OP-AR7). Whole-exome sequencing in a patient with sclerosing bone disease identified novel compound heterozygous variants (c.414_427 + 7del, c.1664del) in TNFRSF11A. We examined the impact of the two variants on five splicing isoforms of TNFRSF11A by RT-PCR. We found that c.1664del resulted in elongated proteins (p.S555Cfs*121, etc.), while c.414_427 + 7del generated two aberrant splicing products (p.A139Wfs*19 and p.E132Dfs*19) that lead to nonsense mediated mRNA decay (NMD). In the previous two cases of TNFRSF11A-associated DOS, their mutations produced truncated TNFRSF11A protein isoforms. The mutations in all three cases thus contrast with TNFRSF11A mutations reported in OP-AR7, which does not generated truncated or elongated TNFRSF11A proteins. Thus, we identified the third case of TNFRSF11A-associated DOS and reinforced the genotype-phenotype correlation that aberrant protein-producing TNFRSF11A mutations cause DOS.


Assuntos
Mutação , Osteosclerose/patologia , Receptor Ativador de Fator Nuclear kappa-B/genética , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Pré-Escolar , Feminino , Humanos , Osteosclerose/genética , Osteosclerose/metabolismo , Prognóstico , Sequenciamento do Exoma
7.
J Bone Miner Res ; 36(3): 531-545, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33125761

RESUMO

ClC-7 is a chloride-proton antiporter of the CLC protein family. In complex with its accessory protein Ostm-1, ClC-7 localizes to lysosomes and to the osteoclasts' ruffled border, where it plays a critical role in acidifying the resorption lacuna during bone resorption. Gene inactivation in mice causes severe osteopetrosis, neurodegeneration, and lysosomal storage disease. Mutations in the human CLCN7 gene are associated with diverse forms of osteopetrosis. The functional evaluation of ClC-7 variants might be informative with respect to their pathogenicity, but the cellular localization of the protein hampers this analysis. Here we investigated the functional effects of 13 CLCN7 mutations identified in 13 new patients with severe or mild osteopetrosis and a known ADO2 mutation. We mapped the mutated amino acid residues in the homology model of ClC-7 protein, assessed the lysosomal colocalization of ClC-7 mutants and Ostm1 through confocal microscopy, and performed patch-clamp recordings on plasma-membrane-targeted mutant ClC-7. Finally, we analyzed these results together with the patients' clinical features and suggested a correlation between the lack of ClC-7/Ostm1 in lysosomes and severe neurodegeneration. © 2020 American Society for Bone and Mineral Research (ASBMR).


Assuntos
Reabsorção Óssea , Osteopetrose , Animais , Canais de Cloreto/genética , Humanos , Lisossomos , Camundongos , Mutação/genética , Osteoclastos , Osteopetrose/genética
8.
Bone Rep ; 14: 100738, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33364264

RESUMO

Autosomal recessive osteopetrosis (ARO) is rare, involving increased bone density due to defective osteoclast differentiation or function, with several genetic subtypes. CASE: This child with compound heterozygous novel loss-of-function TNFRSF11A pathogenic variants causing osteoclast-poor ARO underwent haematopoietic stem cell transplantation (HSCT) aged 3.1 years and experienced episodic severe hypercalcaemia over 2.5 years. She initially presented aged 8 months with craniosynostosis and visual impairment and underwent surgery; no increased bone density evident on skull imaging nor variants in genes associated with craniosynostosis identified. She was subsequently referred for investigation of poor linear growth and low alkaline phosphatase. Clinical abnormalities included asymmetric pectus carinatum, thickened anterior tibia and wrists, and markedly delayed dentition. Skeletal survey revealed generalised osteosclerosis with undertubulation. MANAGEMENT: She received haploidentical HSCT aged 3.1 years and developed hypercalcaemia (adjusted calcium 4.09mmol/L = 16.4mg/dL) Day 18 post-HSCT, unresponsive to hyperhydration and diuretics. Denosumab achieved normocalcaemia, which required 0.6mg/kg every 6 weeks long-term. The ensuing 2.75 years feature full donor engraftment, good HSCT graft function, skeletal remodelling with 2.5 years recurrent severe hypercalcaemia and nine fragility long bone fractures. CONCLUSION: This case illustrates challenges of bone and calcium management in ultrarare TNFRSF11A-related OP-ARO. Craniosynostosis was an early feature, evident pre-sclerosis in osteopetrosis. Following HSCT, restoration of osteoclast activity in the context of elevated bone mass produced severe and prolonged (2.5 years) hypercalcaemia. Denosumab was effective medium-term, but required concurrent long duration (11 months) zoledronic acid to manage recurrent hypercalcaemia. Fragility fractures brought appreciable additional morbidity in the post-HSCT phase.

9.
Am J Med Genet A ; 182(10): 2403-2408, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32783357

RESUMO

Short-rib polydactyly syndromes are a heterogeneous group of disorders characterized by narrow thorax with short ribs, polydactyly and often other visceral and skeletal malformations. To date there have only been six reported patients with homozygous and compound heterozygous variants in IFT81, causing a short-rib thoracic dysplasia, with, or without, polydactyly (SRTD19: OMIM 617895). IFT81 is a protein integral to the core of the intraflagellar transport complex B (IFT-B), which is involved in anterograde transport in the cilium. We describe the case of a male infant with compound heterozygous variants in IFT81, who presented with short long bones, a narrow thorax, polydactyly, and multiple malformations. Three novel clinical features are reported including complete situs inversus, micropenis, and rectal atresia, which have not previously been associated with variants in IFT81. We reviewed the literature and identified the most consistent clinical features associated with this rare ciliopathy syndrome. We postulate that dolichocephaly and sagittal craniosynostosis may be associated with this condition, and provide a clue to considering IFT81 as the causative gene when deciphering complex ciliopathies.


Assuntos
Ciliopatias/genética , Craniossinostoses/genética , Proteínas Musculares/genética , Síndrome de Costela Curta e Polidactilia/genética , Cílios/patologia , Ciliopatias/diagnóstico , Ciliopatias/fisiopatologia , Craniossinostoses/diagnóstico , Craniossinostoses/fisiopatologia , Homozigoto , Humanos , Recém-Nascido , Masculino , Mutação/genética , Fenótipo , Síndrome de Costela Curta e Polidactilia/diagnóstico , Síndrome de Costela Curta e Polidactilia/fisiopatologia
10.
J Pediatr Endocrinol Metab ; 33(7): 951-955, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32447330

RESUMO

Objectives Prader-Willi Syndrome (PWS) is characterised by hyperphagia often leading to obesity; a known risk factor for insulin resistance and type 2 (T2) diabetes. We present a prepubertal girl with PWS who developed diabetes. Case presentation Our case was diagnosed with PWS in infancy following investigation for profound central hypotonia and feeding difficulties. She commenced growth hormone (GH) aged 8 years for short stature and treatment improved linear growth. At age 12 years, she presented with polydipsia, polyuria and vulvovaginitis. She was overweight (BMI SDS +1.43). Diabetes was diagnosed (Blood glucose = 24.2 mmol/L, HbA1c = 121 mmol/mol or 13.2%). She was not acidotic and had negative blood ketones. Autoantibodies typical of type 1 diabetes were negative. She was initially treated with basal bolus insulin regime. GH was discontinued 3 months later due to concerns regarding GH-induced insulin resistance. Off GH, insulin requirements reduced to zero, allowing Metformin monotherapy. However off GH, she reported significant lethargy with static growth and increased weight. Combinations of Metformin with differing insulin regimes did not improve glucose levels. Liraglutide (GLP-1 agonist) and Metformin did not improve glucose levels nor her weight. Liraglutide and Empaglifozin (SGLT-2 inhibitor) therapy used in combination were well tolerated and demonstrated rapid normalisation of blood glucose and improvement in her HbA1c to within target (48 mmol/mol) which was sustained after 6 months of treatment. Conclusions Newer treatments for type 2 diabetes (e. g. GLP-1 agonists or SGLT-2 inhibitors) offer potential treatment options for those with diabetes and PWS when conventional treatments are ineffective.


Assuntos
Compostos Benzidrílicos/administração & dosagem , Diabetes Mellitus/tratamento farmacológico , Glucosídeos/administração & dosagem , Liraglutida/administração & dosagem , Síndrome de Prader-Willi/tratamento farmacológico , Adolescente , Compostos Benzidrílicos/farmacologia , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Criança , Diabetes Mellitus/sangue , Diabetes Mellitus/etiologia , Quimioterapia Combinada , Feminino , Peptídeo 1 Semelhante ao Glucagon/agonistas , Glucosídeos/farmacologia , Humanos , Liraglutida/farmacologia , Síndrome de Prader-Willi/sangue , Síndrome de Prader-Willi/complicações , Inibidores do Transportador 2 de Sódio-Glicose/administração & dosagem , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Resultado do Tratamento
11.
BMC Med Genet ; 21(1): 64, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228492

RESUMO

BACKGROUND: The calcium-selective channel TRPV6 (transient receptor potential cation channel subfamily V member 6) is crucial for maternal-fetal calcium transport across the placenta. TRPV6 mutations have recently been associated with an antenatally severe under-mineralising skeletal dysplasia accompanied by postnatal biochemical abnormalities. This is the first post-mortem report in a patient with TRPV6 skeletal dysplasia. CASE PRESENTATION: The female infant had severe antenatal and postnatal skeletal abnormalities by 20 weeks gestation and was ventilator-dependent from birth. These skeletal abnormalities were apparent at an earlier gestational age than in previous reported cases and a more severe clinical course ensued. Biochemical and skeletal abnormalities, including bone density, improved postnatally but cardiac arrest at 4 months of age led to withdrawal of intensive care. Compound heterozygous TRPV6 variants (c.1978G > C p.(Gly660Arg) and c.1528C > T p.(Arg510Ter)) were identified on exome sequencing. Post-mortem identified skeletal abnormalities but no specific abnormalities in other organ systems. No placental pathology was found, multi-organ histological features reflected prolonged intensive care only. Post-mortem macroscopic examination indicated reduced thoracic size and short, pale and pliable ribs. Histological examination identified reduced number of trabeculae in the diaphyses (away from the growth plates), whereas metaphyses showed adequate mineralisation and normal number of trabeculae, but with slightly enlarged reactive chondrocytes, indicating post-natal skeletal growth recovery. Post-mortem radiological findings demonstrated improved bone density, improved rib width, healed fractures, although ribs were still shorter than normal. Long bones (especially humerus and femur) had improved from initial poorly defined metaphyses and reduced bone density to sharply defined metaphyses, prominent growth restart lines in distal diaphyses and bone-in-bone appearance along diaphyses. CONCLUSIONS: This case provide bone histological confirmation that human skeletal development is compromised in the presence of TRPV6 pathogenic variants. Post-mortem findings were consistent with abnormal in utero skeletal mineralisation due to severe calcium deficit from compromised placental calcium transfer, followed by subsequent phenotypic improvement with adequate postnatal calcium availability. Significant skeletal recovery occurs in the early weeks of postnatal life in TRPV6 skeletal dysplasia.


Assuntos
Desenvolvimento Ósseo , Osso e Ossos/patologia , Canais de Cálcio/genética , Desenvolvimento Infantil/fisiologia , Osteocondrodisplasias/genética , Osteocondrodisplasias/patologia , Canais de Cátion TRPV/genética , Autopsia , Desenvolvimento Ósseo/genética , Osso e Ossos/anormalidades , Calcificação Fisiológica/genética , Cálcio/metabolismo , Canais de Cálcio/análise , Análise Mutacional de DNA , Feminino , Humanos , Lactente , Osteocondrodisplasias/reabilitação , Parto/fisiologia , Canais de Cátion TRPV/análise
13.
Am J Med Genet A ; 176(9): 1950-1955, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30144375

RESUMO

Transient receptor potential vanilloid 6 (TRPV6) functions in tetramer form for calcium transport. Until now, TRPV6 has not been linked with skeletal development disorders. An infant with antenatal onset thoracic insufficiency required significant ventilatory support. Skeletal survey showed generalized marked undermineralization, hypoplastic fractured ribs, metaphyseal fractures, and extensive periosteal reaction along femoral, tibial, and humeral diaphyses. Parathyroid hormone (PTH) elevation (53.4-101 pmol/L) initially suggested PTH signaling disorders. Progressively, biochemical normalization with radiological mineralization suggested recovery from in utero pathophysiology. Genomic testing was undertaken and in silico protein modeling of variants. No abnormalities in antenatal CGH array or UPD14 testing. Postnatal molecular genetic analysis found no causative variants in CASR, GNA11, APS21, or a 336 gene skeletal dysplasia panel investigated by whole exome sequencing. Trio exome analysis identified compound heterozygous TRPV6 likely pathogenic variants: novel maternally inherited missense variant, c.1978G > C p.(Gly660Arg), and paternally inherited nonsense variant, c.1528C > T p.(Arg510Ter), confirming recessive inheritance. p.(Gly660Arg) generates a large side chain protruding from the C-terminal hook into the interface with the adjacent TRPV6 subunit. In silico protein modeling suggests steric clashes between interface residues, decreased C-terminal hook, and TRPV6 tetramer stability. The p.(Gly660Arg) variant is predicted to result in profound loss of TRPV6 activity. This first case of a novel dysplasia features severe but improving perinatal abnormalities. The TRPV6 compound heterozygous variants appear likely to interfere with fetoplacental calcium transfer crucial for in utero skeletal development. Astute clinical interpretation of evolving perinatal abnormalities remains valuable in complex calcium and bone pathophysiology and informs exome sequencing interpretation.


Assuntos
Doenças do Desenvolvimento Ósseo/diagnóstico , Doenças do Desenvolvimento Ósseo/genética , Canais de Cálcio/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Heterozigoto , Canais de Cátion TRPV/genética , Alelos , Canais de Cálcio/química , Hibridização Genômica Comparativa , Exoma , Feminino , Estudos de Associação Genética/métodos , Humanos , Modelos Moleculares , Placenta/metabolismo , Gravidez , Conformação Proteica , Radiografia , Índice de Gravidade de Doença , Relação Estrutura-Atividade , Canais de Cátion TRPV/química , Sequenciamento do Exoma
14.
Artigo em Inglês | MEDLINE | ID: mdl-28469921

RESUMO

SUMMARY: This case, presenting with bilateral impalpable testes, illustrates the relevance of a broad differential disorders of sex development case management. It provides new insights on hypothalamic-pituitary-gonadal (HPG) axis and testicular function abnormalities in the multisystem disorder of Lowe syndrome. Lowe syndrome, also known as oculocerebrorenal syndrome, is a rare disorder characterised by eye abnormalities, central nervous system involvement and proximal renal tubular acidosis. There are a handful of reports of pubertal delay, infertility and cryptorchidism in Lowe syndrome. Biochemistry aged 72 h: testosterone 6.4 nmol/L, LH <0.5 IU/L and FSH <0.5 IU/L. Gonadotropin-releasing hormone stimulation test identified significantly raised baseline LH = 45.4 IU/L (contrasts with earlier undetectable LH), with a 20% increase on stimulation, while baseline FSH = 4.3 IU/L with no increase on stimulation. Day 14 HCG stimulation test produced an acceptable 50% increase in testosterone. The constellation of further abnormalities suggested Lowe syndrome: hypotonia, bilateral cataracts (surgical extraction and intraocular lens implantation) and renal tubular acidosis (microscopic haematuria, hypercalciuria, proteinuria, generalised aminoaciduria, hypophosphataemia and metabolic acidosis). DNA sequencing identified de novo hemizygous frameshift mutation OCRL c.2409_2410delCT in exon 22. Interpretation of initial and repeat GnRH and HCG testing indicates the likelihood of testicular failure. Partial testicular descent occurred but left orchidopexy was required. Improving long-term gonadal function in Lowe syndrome assumes increased importance for current cohorts as advances in renal replacement therapy have greatly improved life expectancy. Noting HPG axis abnormalities in Lowe syndrome in infancy can identify cases requiring increased surveillance of pubertal progress for earlier detection and management. LEARNING POINTS: Clinical endocrine problems in Lowe syndrome has been reported, but has focused on abnormalities in adolescence and young adulthood: pubertal delay and infertility.We present an infant with isolated LH elevation at baseline and on GnRH stimulation testing who also had bilateral impalpable testes.Early testing of the HPG axis in patients with Lowe syndrome may help predict gonadal abnormalities from a younger age, which will enhance the overall case management into adolescence.

15.
Pediatr Diabetes ; 18(8): 835-838, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28093873

RESUMO

Two Caucasian girls, both of normal weight and body mass indices, were diagnosed with type A insulin resistance (IR) in childhood. Case 1 presented with premature adrenarche aged 7 years, then by age 12 years had hirsutism, acne, acanthosis nigricans, and asymptomatic diabetes. Subsequent investigation revealed raised adiponectin (15.3 mg/L) and heterozygous p.Pro1205Leu mutation in the INSR gene encoding the insulin receptor. She experienced postprandial hypoglycaemia on metformin; acarbose was trialled and discontinued aged 16 years, as she became normoglycaemic. Hirsutism was treated with topical eflornithine, oral spironolactone and flutamide, and laser therapy. Unfortunately, diabetes reemerged in young adulthood with obesity. Case 2: during an emergency admission for acute abdominal pain aged 11 years, hyperglycaemia was noted which led to further investigation. An oral glucose tolerance test showed diabetes and ultrasound showed polycystic ovaries. Further investigations revealed raised adiponectin (18 mg/L) and compound heterozygous mutations in the INSR gene: p.Pro1263Ala and p.Ser748Leu (latter probable normal variant). She was treated with metformin and experienced postprandial hypoglycaemia. Symptoms of hyperandrogenism were controlled by flutamide. She maintained a healthy weight and reassessment at young adulthood showed resolution of diabetes. Type A IR may present in childhood with overlapping features of common endocrine entities such as premature adrenarche and polycystic ovarian syndrome. Patients with abnormal glucose tolerance yet normal weight merit screening with adiponectin; raised adiponectin levels prompt insulin receptor mutational analysis. Postprandial hypoglycaemia is characteristic. Management includes optimization of glycaemic control with oral hypoglycaemic agents and maintenance of healthy weight, and controlling the effects of hyperandrogenism.


Assuntos
Antígenos CD/genética , Hiperinsulinismo/complicações , Puberdade , Receptor de Insulina/genética , Criança , Feminino , Humanos , Hiperinsulinismo/tratamento farmacológico , Hiperinsulinismo/genética , Hipoglicemiantes/uso terapêutico , Resistência à Insulina/genética
16.
Radiol Case Rep ; 12(4): 850-853, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29484085

RESUMO

Osteogenesis imperfecta is a hereditary bone dysplasia characterized by bone fragility, deformity, and short stature. Treatment focuses on preventing bone fractures and symptom relief. Pamidronate, a second-generation bisphosphonate drug that minimizes bone loss, is the chosen treatment in osteogenesis imperfecta. Radiologically, each cycle of pamidronate treatment is depicted as a line of sclerosed nondecalcified cartilage at the metaphysis, termed a pamidronate line. In this case report, we demonstrate that a treatment timeline can be visualized on plain radiographs as the number and spacing of pamidronate lines reflects the number and timing of treatment cycles. The educational value of this is to reassure physicians of the benign nature of "zebra lines," to demonstrate that the pamidronate lines migrate and fade with bone growth, and alert physicians that the lack of expected pamidronate lines during treatment may reflect a change in the patient's condition that reduces the effectiveness of bisphosphonate infusions.

17.
Acta Neuropathol Commun ; 4(1): 56, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27245663

RESUMO

Non-syndromic pituitary gigantism can result from AIP mutations or the recently identified Xq26.3 microduplication causing X-linked acrogigantism (XLAG). Within Xq26.3, GPR101 is believed to be the causative gene, and the c.924G > C (p.E308D) variant in this orphan G protein-coupled receptor has been suggested to play a role in the pathogenesis of acromegaly.We studied 153 patients (58 females and 95 males) with pituitary gigantism. AIP mutation-negative cases were screened for GPR101 duplication through copy number variation droplet digital PCR and high-density aCGH. The genetic, clinical and histopathological features of XLAG patients were studied in detail. 395 peripheral blood and 193 pituitary tumor DNA samples from acromegaly patients were tested for GPR101 variants.We identified 12 patients (10 females and 2 males; 7.8 %) with XLAG. In one subject, the duplicated region only contained GPR101, but not the other three genes in found to be duplicated in the previously reported patients, defining a new smallest region of overlap of duplications. While females presented with germline mutations, the two male patients harbored the mutation in a mosaic state. Nine patients had pituitary adenomas, while three had hyperplasia. The comparison of the features of XLAG, AIP-positive and GPR101&AIP-negative patients revealed significant differences in sex distribution, age at onset, height, prolactin co-secretion and histological features. The pathological features of XLAG-related adenomas were remarkably similar. These tumors had a sinusoidal and lobular architecture. Sparsely and densely granulated somatotrophs were admixed with lactotrophs; follicle-like structures and calcifications were commonly observed. Patients with sporadic of familial acromegaly did not have an increased prevalence of the c.924G > C (p.E308D) GPR101 variant compared to public databases.In conclusion, XLAG can result from germline or somatic duplication of GPR101. Duplication of GPR101 alone is sufficient for the development of XLAG, implicating it as the causative gene within the Xq26.3 region. The pathological features of XLAG-associated pituitary adenomas are typical and, together with the clinical phenotype, should prompt genetic testing.


Assuntos
Duplicação Gênica , Gigantismo/genética , Receptores Acoplados a Proteínas G/genética , Acromegalia/complicações , Acromegalia/genética , Acromegalia/patologia , Adenoma/complicações , Adenoma/genética , Adenoma/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Mutação em Linhagem Germinativa , Gigantismo/complicações , Gigantismo/patologia , Gigantismo/terapia , Humanos , Lactente , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/patologia , Resultado do Tratamento , Adulto Jovem
19.
PLoS One ; 10(10): e0137562, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26465770

RESUMO

AIMS: To investigate young people's attitudes to, and understanding of, physical activity on glycaemic control in Type 1 Diabetes Mellitus. METHODS: Four focus groups with 11-14 and 15-16 year olds were conducted with twelve young people with Type 1 Diabetes, from within a larger study investigating physical activity and fitness. Qualitative analysis of the focus group data was performed using Interpretative Phenomenological Analysis. RESULTS: Four superordinate themes were identified: Benefits of Exercise, Knowledge and Understanding, Information and Training and "You can do anything". Young people felt that exercising helped them to manage their diabetes and had a beneficial psychological and physical impact on their bodies. They reported a lack of knowledge and understanding about diabetes among school staff and other young people. The overwhelming sense from young people was that although diabetes impacts upon their lives, with preparation, physical activity can take place as normal. CONCLUSIONS: Whilst young people had an awareness of the physical and psychological benefits of exercise in managing their diabetes, they experienced difficulties at school. Professional support and discussions with young people, giving tailored strategies for managing Type 1 Diabetes during exercise are needed. Healthcare teams should ensure that the support and educational needs of school staff are met. Providing more opportunities to empower young people to take on the responsibility for their Type 1 Diabetes care is merited. Young people felt diabetes did not stop them from participating in activities; it is simply a part of them that needs managing throughout life.


Assuntos
Atitude Frente a Saúde , Diabetes Mellitus Tipo 1/fisiopatologia , Exercício Físico , Adolescente , Criança , Diabetes Mellitus Tipo 1/psicologia , Terapia por Exercício , Feminino , Grupos Focais , Humanos , Estilo de Vida , Masculino , Pesquisa Qualitativa , Inquéritos e Questionários
20.
Lancet ; 382(9902): 1424-32, 2013 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-23927913

RESUMO

BACKGROUND: Children with osteogenesis imperfecta are often treated with intravenous bisphosphonates. We aimed to assess the safety and efficacy of risedronate, an orally administered third-generation bisphosphonate, in children with the disease. METHODS: In this multicentre, randomised, parallel, double-blind, placebo-controlled trial, children aged 4-15 years with osteogenesis imperfecta and increased fracture risk were randomly assigned by telephone randomisation system in a 2:1 ratio to receive either daily risedronate (2·5 or 5 mg) or placebo for 1 year. Study treatment was masked from patients, investigators, and study centre personnel. Thereafter, all children received risedronate for 2 additional years in an open-label extension. The primary efficacy endpoint was percentage change in lumbar spine areal bone mineral density (BMD) at 1 year. The primary efficacy analysis was done by ANCOVA, with treatment, age group, and pooled centre as fixed effects, and baseline as covariate. Analyses were based on the intention-to-treat population, which included all patients who were randomly assigned and took at least one dose of assigned study treatment. The trial is registered with ClinicalTrials.gov, number NCT00106028. FINDINGS: Of 147 patients, 97 were randomly assigned to the risedronate group and 50 to the placebo group. Three patients from the risedronate group and one from the placebo group did not receive study treatment, leaving 94 and 49 in the intention-to-treat population, respectively. The mean increase in lumbar spine areal BMD after 1 year was 16·3% in the risedronate group and 7·6% in the placebo group (difference 8·7%, 95% CI 5·7-11·7; p<0·0001). After 1 year, clinical fractures had occurred in 29 (31%) of 94 patients in the risedronate group and 24 (49%) of 49 patients in the placebo group (p=0·0446). During years 2 and 3 (open-label phase), clinical fractures were reported in 46 (53%) of 87 patients in the group that had received risedronate since the start of the study, and 32 (65%) of 49 patients in the group that had been given placebo during the first year. Adverse event profiles were otherwise similar between the two groups, including frequencies of reported upper-gastrointestinal and selected musculoskeletal adverse events. INTERPRETATION: Oral risedronate increased areal BMD and reduced the risk of first and recurrent clinical fractures in children with osteogenesis imperfecta, and the drug was generally well tolerated. Risedronate should be regarded as a treatment option for children with osteogenesis imperfecta. FUNDING: Alliance for Better Bone Health (Warner Chilcott and Sanofi).


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Ácido Etidrônico/análogos & derivados , Osteogênese Imperfeita/tratamento farmacológico , Administração Oral , Adolescente , Fosfatase Alcalina/metabolismo , Análise de Variância , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/efeitos adversos , Criança , Pré-Escolar , Colágeno/metabolismo , Método Duplo-Cego , Esquema de Medicação , Ácido Etidrônico/administração & dosagem , Ácido Etidrônico/efeitos adversos , Feminino , Humanos , Masculino , Osteogênese Imperfeita/fisiopatologia , Ácido Risedrônico , Resultado do Tratamento
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