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1.
Am J Med Genet A ; 179(10): 1987-2033, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31418527

RESUMO

Turner syndrome is recognized now as a syndrome familiar not only to pediatricians and pediatric specialists, medical geneticists, adult endocrinologists, and cardiologists, but also increasingly to primary care providers, internal medicine specialists, obstetricians, and reproductive medicine specialists. In addition, the care of women with Turner syndrome may involve social services, and various educational and neuropsychologic therapies. This article focuses on the recognition and management of Turner syndrome from adolescents in transition, through adulthood, and into another transition as older women. It can be viewed as an interpretation of recent international guidelines, complementary to those recommendations, and in some instances, an update. An attempt was made to provide an international perspective. Finally, the women and families who live with Turner syndrome and who inspired several sections, are themselves part of the broad readership that may benefit from this review.


Assuntos
Síndrome de Turner/diagnóstico , Síndrome de Turner/terapia , Adolescente , Adulto , Idoso , Criança , Cromossomos Humanos Y/genética , Humanos , Cariótipo , Saúde Mental , Pessoa de Meia-Idade , Fenótipo , Síndrome de Turner/epidemiologia , Síndrome de Turner/genética , Adulto Jovem
2.
Curr Diab Rep ; 19(9): 71, 2019 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-31367971

RESUMO

PURPOSE OF REVIEW: Klinefelter syndrome (KS) is associated with increased insulin resistance and high rates of type 2 diabetes (T2DM). Our aim was to review what is known about the prevalence of diabetes in men with KS, potential mechanisms underlying the observed metabolic phenotype, and the data that are available to guide treatment decisions. RECENT FINDINGS: The increased prevalence of T2DM seen in men with KS appears to be the result of multiple mechanisms including increased truncal adiposity and socioeconomic disadvantages, but it is likely not a direct consequence of hypogonadism alone. No randomized trials have been conducted to evaluate the impact of testosterone replacement therapy on T2DM in men with KS, but observational data suggest that testosterone replacement is not associated with lower rates of diabetes or improved glycemic control. Metabolic derangements are common in KS, but treatment strategies specific to this population are lacking. Early lifestyle and dietary interventions are likely important. Additional research is needed to dissect the complex interaction between genotype and metabolic phenotype. Collaboration between academic centers caring for men with KS is needed to facilitate the development of evidence-based clinical practice guidelines, which would inform optimal screening and treatment strategies for this patient population.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Síndrome de Klinefelter/metabolismo , Androgênios/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Terapia de Reposição Hormonal/métodos , Humanos , Resistência à Insulina , Síndrome de Klinefelter/complicações , Masculino , Prevalência , Testosterona/uso terapêutico
3.
Clin Endocrinol (Oxf) ; 78(2): 291-6, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22804876

RESUMO

OBJECTIVE: This study examines the physiological impact of a glucose load on serum testosterone (T) levels in men with varying glucose tolerance (GT). DESIGN: Cross-sectional study. PATIENTS AND METHODS: 74 men (19-74 years, mean 51·4 ± 1·4 years) underwent a standard 75-g oral glucose tolerance test with blood sampling at 0, 30, 60, 90 and 120 min. Fasting serum glucose, insulin, total T (and calculated free T), LH, SHBG, leptin and cortisol were measured. RESULTS: 57% of the men had normal GT, 30% had impaired GT and 13% had newly diagnosed type 2 diabetes. Glucose ingestion was associated with a 25% decrease in mean T levels (delta = -4·2 ± 0·3 nm, P < 0·0001). T levels remained suppressed at 120 min compared with baseline (13·7 ± 0·6 vs 16·5 ± 0·7 nm, P < 0·0001) and did not differ across GT or BMI. Of the 66 men with normal T levels at baseline, 10 (15%) had levels that decreased to the hypogonadal range (<9·7 nm) at one or more time points. SHBG, LH and cortisol levels were unchanged. Leptin levels decreased from baseline at all time points (P < 0·0001). CONCLUSIONS: Glucose ingestion induces a significant reduction in total and free T levels in men, which is similar across the spectrum of glucose tolerance. This decrease in T appears to be because of a direct testicular defect, but the absence of compensatory changes in LH suggests an additional central component. Men found to have low nonfasting T levels should be re-evaluated in the fasting state.


Assuntos
Glucose/administração & dosagem , Hipogonadismo/diagnóstico , Testosterona/sangue , Administração Oral , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Endocrinol Metab Clin North Am ; 51(1): 99-108, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35216723

RESUMO

For hypogonadal men treated with testosterone, the goal is to ensure that benefits are optimized, risks are minimized, and any adverse effects are identified early and managed appropriately. This can best be achieved by careful patient selection, excluding men with contraindications and addressing any modifiable risk factors in those at increased risk. A standardized plan should be used for monitoring that includes evaluation of symptoms, side effects, adherence, and measurement of testosterone and hematocrit. Shared decision making should be used to determine whether to screen for prostate cancer and informed by age, baseline cancer risk, and patient preference.


Assuntos
Hipogonadismo , Neoplasias da Próstata , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Hipogonadismo/tratamento farmacológico , Masculino , Razão de Chances , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/tratamento farmacológico , Testosterona/efeitos adversos
5.
Eur J Med Genet ; 64(3): 104140, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33524610

RESUMO

Despite numerous clinical series, consistent karyotype-phenotype correlations for Turner syndrome have not been established, although a lower level of 45,X is generally thought to be associated with a milder phenotype. This limits personalized counseling for women with 45,X/46,XX mosaicism. To better understand the phenotypic spectrum associated with various levels of 45,X/46,XX mosaicism, we compared patients evaluated in the Massachusetts General Hospital Turner Syndrome Clinic to determine if cardiac, renal, and thyroid abnormalities correlated with the percentage of 45,X cells present in a peripheral blood karyotype. of the 118 patients included in the study, 78 (66%) patients had non-mosaic 45,X and 40 (34%) patients had varying levels of 45,X/46,XX mosaicism. Patients with ≤70% 45,X compared with those with >70% 45,X had a significantly lower frequency of cardiac and renal anomalies. The presence of hypothyroidism was somewhat lower for the ≤70% 45,X group, but was not statistically significant. Supplemental tissue testing on another tissue type, typically buccal mucosa, was often useful in counseling patients with 45,X mosaicism. Given the modest sample size of patients with varying levels of mosaicism and the variability of Turner syndrome abnormalities, we hope this preliminary study will inspire a multicenter collaboration, which may lead to modification of clinical guidelines. Because several patients with ≤70% 45,X were ascertained from perinatal care referrals, we still advise women with 45,X mosaicism pursuing pregnancy to receive standard Turner syndrome cardiac surveillance. There is an opportunity to personalize counseling and surveillance for patients based on percentage of 45,X cells on chromosome analysis.


Assuntos
Transtornos 46, XX do Desenvolvimento Sexual/genética , Testes Genéticos/métodos , Cariotipagem/métodos , Mosaicismo , Fenótipo , Medicina de Precisão/métodos , Síndrome de Turner/genética , Transtornos 46, XX do Desenvolvimento Sexual/diagnóstico , Células Cultivadas , Feminino , Testes Genéticos/normas , Humanos , Cariotipagem/normas , Medicina de Precisão/normas , Síndrome de Turner/diagnóstico
6.
J Clin Invest ; 117(2): 457-63, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17235395

RESUMO

Idiopathic hypogonadotropic hypogonadism (IHH) due to defects of gonadotropin-releasing hormone (GnRH) secretion and/or action is a developmental disorder of sexual maturation. To date, several single-gene defects have been implicated in the pathogenesis of IHH. However, significant inter- and intrafamilial variability and apparent incomplete penetrance in familial cases of IHH are difficult to reconcile with the model of a single-gene defect. We therefore hypothesized that mutations at different IHH loci interact in some families to modify their phenotypes. To address this issue, we studied 2 families, one with Kallmann syndrome (IHH and anosmia) and another with normosmic IHH, in which a single-gene defect had been identified: a heterozygous FGF receptor 1 (FGFR1) mutation in pedigree 1 and a compound heterozygous gonadotropin-releasing hormone receptor (GNRHR) mutation in pedigree 2, both of which varied markedly in expressivity within and across families. Further candidate gene screening revealed a second heterozygous deletion in the nasal embryonic LHRH factor (NELF) gene in pedigree 1 and an additional heterozygous FGFR1 mutation in pedigree 2 that accounted for the considerable phenotypic variability. Therefore, 2 different gene defects can synergize to produce a more severe phenotype in IHH families than either alone. This genetic model could account for some phenotypic heterogeneity seen in GnRH deficiency.


Assuntos
Hipogonadismo/genética , Mutação , Adulto , Sequência de Aminoácidos , Sequência de Bases , Sequência Conservada , DNA/genética , Feminino , Fator 8 de Crescimento de Fibroblasto/metabolismo , Genótipo , Hormônio Liberador de Gonadotropina/deficiência , Heterozigoto , Humanos , Hipogonadismo/etiologia , Hipogonadismo/metabolismo , Síndrome de Kallmann/genética , Masculino , Modelos Genéticos , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Fenótipo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/química , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Receptores LHRH/genética , Deleção de Sequência , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/genética
7.
N Engl J Med ; 357(9): 863-73, 2007 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-17761590

RESUMO

BACKGROUND: Idiopathic hypogonadotropic hypogonadism, which may be associated with anosmia (the Kallmann syndrome) or with a normal sense of smell, is a treatable form of male infertility caused by a congenital defect in the secretion or action of gonadotropin-releasing hormone (GnRH). Patients have absent or incomplete sexual maturation by the age of 18. Idiopathic hypogonadotropic hypogonadism was previously thought to require lifelong therapy. We describe 15 men in whom reversal of idiopathic hypogonadotropic hypogonadism was sustained after discontinuation of hormonal therapy. METHODS: We defined the sustained reversal of idiopathic hypogonadotropic hypogonadism as the presence of normal adult testosterone levels after hormonal therapy was discontinued. RESULTS: Ten sustained reversals were identified retrospectively. Five sustained reversals were identified prospectively among 50 men with idiopathic hypogonadotropic hypogonadism after a mean (+/-SD) duration of treatment interruption of 6+/-3 weeks. Of the 15 men who had a sustained reversal, 4 had anosmia. At initial evaluation, 6 men had absent puberty, 9 had partial puberty, and all had abnormal secretion of GnRH-induced luteinizing hormone. All 15 men had received previous hormonal therapy to induce virilization, fertility, or both. Among those whose hypogonadism was reversed, the mean serum level of endogenous testosterone increased from 55+/-29 ng per deciliter (1.9+/-1.0 nmol per liter) to 386+/-91 ng per deciliter (13.4+/-3.2 nmol per liter, P<0.001), the luteinizing hormone level increased from 2.7+/-2.0 to 8.5+/-4.6 IU per liter (P<0.001), the level of follicle-stimulating hormone increased from 2.5+/-1.7 to 9.5+/-12.2 IU per liter (P<0.01), and testicular volume increased from 8+/-5 to 16+/-7 ml (P<0.001). Pulsatile luteinizing hormone secretion and spermatogenesis were documented. CONCLUSIONS: Sustained reversal of normosmic idiopathic hypogonadotropic hypogonadism and the Kallmann syndrome was noted after discontinuation of treatment in about 10% of patients with either absent or partial puberty. Therefore, brief discontinuation of hormonal therapy to assess reversibility of hypogonadotropic hypogonadism is reasonable. (ClinicalTrials.gov number, NCT00392756 [ClinicalTrials.gov].).


Assuntos
Hormônio Liberador de Gonadotropina/deficiência , Hipogonadismo/congênito , Testosterona/sangue , Adolescente , Adulto , Proteínas da Matriz Extracelular/genética , Seguimentos , Hormônio Liberador de Gonadotropina/uso terapêutico , Gonadotropinas/sangue , Gonadotropinas/uso terapêutico , Humanos , Hipogonadismo/sangue , Hipogonadismo/tratamento farmacológico , Síndrome de Kallmann/sangue , Síndrome de Kallmann/tratamento farmacológico , Masculino , Mutação , Proteínas do Tecido Nervoso/genética , Linhagem , Estudos Prospectivos , Puberdade Tardia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptores Acoplados a Proteínas G/genética , Receptores de Kisspeptina-1 , Receptores LHRH/genética , Remissão Espontânea , Testosterona/deficiência , Testosterona/uso terapêutico
8.
Endocr Res ; 35(2): 71-84, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20408755

RESUMO

INTRODUCTION: Evidence supports an inverse relationship between serum testosterone (T) and insulin resistance in men. However, data with respect to causality are limited. The aim of this study was to explore the impact of acute biochemical castration on insulin sensitivity in healthy adult men. METHODS: Ten healthy, adult males (mean age 41.0 +/- 3.9 yr) were studied. Subjects were studied at baseline and after 2 and 4 weeks of biochemical castration. Outpatient hospital research setting. Body composition (dual-energy x-ray absorptiometry), energy expenditure (indirect calorimetry), abdominal and visceral adiposity (MRI), skeletal muscle intramyocellular lipid content ([IMCL] (1)H-MR spectroscopy), and insulin sensitivity (hyperinsulinemic-euglycemic clamp) were assessed before and after 2 and 4 weeks of biochemical castration induced by a GnRH antagonist (acyline 300 mug/kg subcutaneous every 10-14 days). Serum T, insulin and glucose levels, body composition, abdominal visceral fat, IMCL, and glucose disposal rate (M) were measured. RESULTS AND CONCLUSION: Acyline administration suppressed serum T to frankly hypogonadal levels in all subjects for the duration of the study (P <0.009). No significant changes in body composition, energy expenditure, or M were observed at either 2 or 4 weeks of castration. Acyline is an effective GnRH antagonist inducing acute castration in all subjects. ii) Four weeks of biochemical castration has no impact on insulin sensitivity in healthy men likely due to unchanged body composition variables. iii) Insulin resistance associated with chronic low T levels may be largely driven by decreased fat free mass, increased percent body fat, and/or other metabolic regulatory factors.


Assuntos
Resistência à Insulina/fisiologia , Insulina/sangue , Orquiectomia , Testosterona/sangue , Adulto , Idoso , Glicemia/metabolismo , Composição Corporal/fisiologia , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Humanos , Gordura Intra-Abdominal/metabolismo , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Oligopeptídeos/administração & dosagem , Globulina de Ligação a Hormônio Sexual/metabolismo , Gordura Subcutânea/metabolismo , Adulto Jovem
9.
Ann Neurol ; 64(2): 200-11, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18756476

RESUMO

OBJECTIVE: To evaluate development of components of polycystic ovary syndrome (PCOS) and PCOS in women with epilepsy initiating valproate or lamotrigine therapy. METHODS: Female individuals with epilepsy and regular menstrual cycles were eligible for this prospective study. Participants were randomized to 12 months of valproate (n = 225) or lamotrigine (n = 222) therapy. Serum androgen levels were measured every 3 months. Urinary pregnanediol glucuronide levels were measured weekly for two 3-month periods. The primary end point was development of PCOS components (ie, hyperandrogenism or ovulatory dysfunction). A post hoc analysis was conducted in women more than 2 years after menarche (177 lamotrigine, (HA) 186 valproate) to exclude OD the confounding effect of puberty. RESULTS: More women in the valproate group than the lamotrigine group developed (OD) in the prospective (54% valproate, 38% lamotrigine; p = 0.010) and the post hoc (HA) analyses (36% valproate, 23% lamotrigine; p = 0.007). More women in the valproate group than the lamotrigine group developed PCOS (9 vs 2%; p = 0.007). Development of HA was more frequent with OD valproate than lamotrigine among those initiating treatment at age younger than 26 years (44% valproate, 23% lamotrigine; p = 0.002) but was similar if treatment was started at age 26 years or older (24% valproate, 22% lamotrigine). INTERPRETATION: Development of HA occurred more frequently with valproate than lamotrigine, especially if medication was started at age younger than 26 years.


Assuntos
Hiperandrogenismo/tratamento farmacológico , Ovulação/efeitos dos fármacos , Síndrome do Ovário Policístico/tratamento farmacológico , Triazinas/uso terapêutico , Ácido Valproico/uso terapêutico , Adolescente , Adulto , Anovulação/induzido quimicamente , Anovulação/tratamento farmacológico , Epilepsia/tratamento farmacológico , Feminino , Humanos , Hiperandrogenismo/induzido quimicamente , Internacionalidade , Lamotrigina , Ovulação/fisiologia , Síndrome do Ovário Policístico/induzido quimicamente , Estudos Prospectivos , Triazinas/efeitos adversos , Triazinas/farmacologia , Ácido Valproico/efeitos adversos , Ácido Valproico/farmacologia
10.
Neuroendocrinology ; 90(3): 260-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19829004

RESUMO

BACKGROUND: The onset of sexual maturation at puberty is a unique developmental period from a neuroendocrine perspective in that it is characterized by enhanced FSH secretion and FSH responsiveness to exogenous GnRH (vs. LH) from the gonadotrope, yet the mechanism of these dynamics remains unclear. This study aimed to elucidate this phenomenon using a human disease model of GnRH deficiency (idiopathic hypogonadotropic hypogonadism, IHH) in which GnRH input can be experimentally controlled. METHODS: 25 GnRH-deficient men were selected for study based upon their baseline testicular volumes (TV) and serum inhibin B (I(B)) levels to represent a spectrum of pubertal/testicular development. Subjects underwent: (i) a 12-hour overnight neuroendocrine evaluation for hormonal profiling and determination of endogenous LH secretion pattern, and (ii) a 7-day exposure to a physiologic regimen of exogenous pulsatile GnRH (25 ng/kg every 2 h). Daily measurements of serum testosterone (T) and I(B) levels were made and a 2-hour window of frequent blood sampling was monitored to measure LH and FSH following a single i.v. GnRH bolus (25 ng/kg). All subjects were screened for known loci underlying GnRH deficiency and the response to GnRH was tracked according to genotype. RESULTS: Among the entire cohort, no changes were noted in serum T or I(B) during the 7 days, thus keeping gonadal feedback relatively constant. However, serum LH and FSH levels increased significantly (p < 0.0001) in the entire cohort. When analyzed by degree of pubertal/testicular development, men with no evidence of prior spontaneous pubertal development (TV 3 ml, Group II, p < 0.0001). Group I exhibited a decreased LH response to GnRH on day 2 compared to day 1 (p < 0.01), which did not recover until day 5 (1-4 vs. 5-7 days, p < 0.0001). Group II displayed robust and equivalent LH responses to GnRH throughout the 7-day study. Genetic studies identified 8 mutations in 4 different loci (DAX1, KAL1, GNRHR, and FGFR1) in this cohort. CONCLUSIONS: GnRH-deficient men undergoing GnRH-induced sexual maturation display an inverse relationship between FSH responsiveness to GnRH and baseline testicular size and I(B) levels. This observation implies that increasing seminiferous tubule maturity represents the major constraint on FSH responsiveness to GnRH in early puberty. In contrast, LH responsiveness to GnRH correlates directly with duration of GnRH exposure. Attenuated pituitary gonadotropin responses were noted in subjects harboring DAX1 mutations, consistent with known pituitary defects.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Luteinizante/metabolismo , Puberdade/fisiologia , Túbulos Seminíferos/crescimento & desenvolvimento , Adulto , Estudos de Coortes , Receptor Nuclear Órfão DAX-1/genética , Proteínas da Matriz Extracelular/genética , Hormônio Foliculoestimulante/sangue , Genótipo , Hormônio Liberador de Gonadotropina/deficiência , Hormônio Liberador de Gonadotropina/genética , Humanos , Inibinas/sangue , Hormônio Luteinizante/sangue , Masculino , Mutação , Proteínas do Tecido Nervoso/genética , Tamanho do Órgão , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptores LHRH/genética , Túbulos Seminíferos/patologia , Testosterona/sangue , Fatores de Tempo
11.
Horm Res Paediatr ; 92(5): 328-334, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31563903

RESUMO

BACKGROUND: Liver function test (LFT) abnormalities, which may reflect underlying pathophysiology, are a well-known feature of Turner syndrome. Less frequently, liver findings may include vascular changes and, rarely, severe liver disease. Although previous studies on children and adolescents suggest a frequency of LFT abnormalities of up to 60%, less is known about the age at onset and natural history. METHODS: We report a now 19-year-old young woman with Turner syndrome mosaicism with elevated transaminase levels first detected at the age of 2 years. We also present a retrospective analysis of 179 girls and women followed in the MassGeneral Hospital Turner Syndrome Clinic. RESULTS: In the index case, the severity of liver function test abnormalities fluctuated without complete resolution from 2 to 18 years of age. In the full cohort of 179 patients, when lab results were available, elevated ALT levels occurred in 16 (11%) subjects of all ages, and in 5 (10%) patients ≤18 years of age. Significant and persistent ALT elevations occurred in 2 patients <10 years of age. CONCLUSION: The updated Clinical Practice Guidelines for the care of girls and women with Turner syndrome recommend annual liver function tests throughout the lifespan, starting at the age of 10 years. Based on our data showing persistent elevation of at least one liver enzyme, we recommend a prospective and more comprehensive study of liver function in younger patients with Turner syndrome. An improved estimate of prevalence could better inform age-adjusted guidelines.


Assuntos
Terapia de Reposição de Estrogênios , Hepatopatias , Síndrome de Turner , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Hepatopatias/sangue , Hepatopatias/patologia , Hepatopatias/terapia , Testes de Função Hepática , Síndrome de Turner/sangue , Síndrome de Turner/patologia , Síndrome de Turner/terapia
12.
J Clin Endocrinol Metab ; 104(8): 3403-3414, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31220265

RESUMO

CONTEXT: After completion of puberty a subset of men experience functional hypogonadotropic hypogonadism (FHH) secondary to excessive exercise or weight loss. This phenomenon is akin to hypothalamic amenorrhea (HA) in women, yet little is known about FHH in men. OBJECTIVE: To investigate the neuroendocrine mechanisms, genetics, and natural history underlying FHH. DESIGN: Retrospective study in an academic medical center. PARTICIPANTS: Healthy postpubertal men presenting with symptoms of hypogonadism in the setting of excessive exercise (>10 hours/week) or weight loss (>10% of body weight). Healthy age-matched men served as controls. INTERVENTIONS: Clinical assessment, biochemical and neuroendocrine profiling, body composition, semen analysis, and genetic evaluation of genes known to cause isolated GnRH deficiency. MAIN OUTCOME MEASURES: Reproductive hormone levels, endogenous GnRH-induced LH pulse patterns, and rare genetic variants. RESULTS: Ten men with FHH were compared with 18 age-matched controls. Patients had significantly lower body mass index, testosterone, LH, and mean LH pulse amplitudes yet normal LH pulse frequency, serum FSH, and sperm counts. Some patients exhibited nocturnal, sleep-entrained LH pulses characteristic of early puberty, and one FHH subject showed a completely apulsatile LH secretion. After decreased exercise and weight gain, five men with men had normalized serum testosterone levels, and symptoms resolved. Rare missense variants in NSMF (n = 1) and CHD7 (n = 1) were identified in two men with FHH. CONCLUSIONS: FHH is a rare, reversible form of male GnRH deficiency. LH pulse patterns in male FHH are similar to those observed in women with HA. This study expands the spectrum of GnRH deficiency disorders in men.


Assuntos
Hormônio Liberador de Gonadotropina/deficiência , Hipogonadismo/fisiopatologia , Sistemas Neurossecretores/fisiopatologia , Adolescente , Humanos , Hipogonadismo/genética , Hormônio Luteinizante/sangue , Masculino , Mutação de Sentido Incorreto , Estudos Retrospectivos , Fatores de Transcrição/genética , Adulto Jovem
13.
J Clin Endocrinol Metab ; 93(9): 3403-10, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18559915

RESUMO

CONTEXT: Low sex hormone levels have been associated with the metabolic syndrome (MetS). OBJECTIVES: Our objective was to determine whether the association between sex hormone levels and MetS varies by race/ethnicity among men and to investigate the relationship of sex hormones and individual components of MetS. DESIGN: We conducted a population-based observational survey. PARTICIPANTS: A multistage stratified design was used to recruit a random sample of 2301 racially/ethnically diverse men age 30-79 yr. Blood samples were obtained on 1899 men. Analyses were conducted on 1885 men with complete data on total testosterone (T), free T, and SHBG. INTERVENTIONS: There were no interventions. MAIN OUTCOME MEASURE: MetS was defined using a modification of the Adult Treatment Panel III guidelines. The association between MetS and sex hormone levels was assessed using odds ratios and 95% confidence intervals estimated using logistic regression models. RESULTS: A strong inverse association was observed, in both bivariate and multivariate analyses, between hormone levels and MetS. The odds of MetS increased about two-fold with a 1 sd decrease in hormone levels. The association between sex hormones and MetS was statistically significant across racial/ethnic groups. Although the magnitude of this association was largest among White men, racial/ethnic differences were not statistically significant. The strength of the association of sex hormones with individual components of MetS varied; stronger associations were observed with waist circumference and dyslipidemia and more modest associations with diabetes and elevated blood sugar. CONCLUSIONS: A robust, dose-response relationship between sex hormone levels and odds of the metabolic syndrome in men is consistent across racial/ethnic groups.


Assuntos
Etnicidade , Síndrome Metabólica/etnologia , Grupos Raciais , Testosterona/sangue , Adulto , Idoso , Suscetibilidade a Doenças/sangue , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Razão de Chances , Globulina de Ligação a Hormônio Sexual/análise , Estados Unidos/epidemiologia
14.
J Clin Endocrinol Metab ; 93(3): 784-91, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18073301

RESUMO

CONTEXT: Studies on the regulation of LH secretion by sex steroids in men are conflicting. OBJECTIVE: Our aims were to determine the relative contributions of testosterone (T) and estradiol (E2) to LH regulation and localize their sites of negative feedback. DESIGN: This was a prospective study with three arms. SETTING: The study was conducted at a General Clinical Research Center. PATIENTS OR OTHER PARTICIPANTS: Twenty-two normal (NL) men and 11 men with GnRH deficiency due to idiopathic hypogonadotropic hypogonadism (IHH) participated. INTERVENTION: Medical castration and inhibition of aromatase were achieved using high-dose ketoconazole (KC) for 7 d with 1) no sex steroid add-back; 2) T enanthate 125 mg im starting on d 4; or 3) E2 patch 37.5 microg/d starting on d 4. Blood sampling was performed every 10 min for 12 h at baseline, overnight on d 3-4 and d 6-7. MAIN OUTCOME MEASURES: Mean LH levels, LH pulse amplitude, and GnRH pulse frequency were assessed at baseline, d 3-4, and d 6-7. RESULTS: In NL men, KC caused a 3-fold increase in mean LH on d 3-4, which was stable on d 6-7 with no add-back. Addition of T reduced LH levels (34.6+/-3.9 to 17.4+/-3.6 IU/liter, P<0.05) by slowing GnRH pulse frequency (13.3+/-0.4 to 6.7+/-1.0 pulses/12 h, P<0.005). LH amplitude increased (6.9+/-1.0 to 12.1+/-1.4 IU/liter, P<0.005). E2 add-back suppressed LH levels (36.4+/-5.6 to 19.0+/-2.4 IU/liter, P<0.005), by slowing GnRH pulse frequency (11.4+/-0.2 to 8.6+/-0.4 pulses/12 h, P<0.05) and had no impact on LH pulse amplitude. In IHH men, restoring normal T levels caused no suppression of mean LH levels or LH amplitude. E2 add-back normalized mean LH levels and decreased LH amplitude from 14.7+/-1.7 to 12+/-1.5 IU/liter (P<0.05). CONCLUSIONS: 1) T and E2 have independent effects on LH. 2) Inhibition of LH by T requires aromatization for its pituitary, but not hypothalamic effects. 3) E2 negative feedback on LH occurs at the hypothalamus.


Assuntos
Hormônio Liberador de Gonadotropina/deficiência , Hipotálamo/efeitos dos fármacos , Hormônio Luteinizante/antagonistas & inibidores , Hipófise/efeitos dos fármacos , Testosterona/farmacologia , Adulto , Inibidores da Aromatase/farmacologia , Estradiol/metabolismo , Estradiol/farmacologia , Retroalimentação Fisiológica , Humanos , Hipogonadismo/metabolismo , Cetoconazol/farmacologia , Hormônio Luteinizante/metabolismo , Masculino , Estudos Prospectivos , Testosterona/metabolismo
15.
J Clin Endocrinol Metab ; 93(5): 1809-14, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18270253

RESUMO

CONTEXT AND OBJECTIVE: Our aim was to explore the relative roles of gonadal sex steroids and inhibin B in the regulation of FSH across a spectrum of seminiferous epithelium function. SUBJECTS: The study included three groups: group I, healthy men (n = 31); group II, men with idiopathic hypogonadotropic hypogonadism receiving pulsatile GnRH (n = 12) selected to represent a spectrum of seminiferous tubular development, testicular size, and baseline inhibin B levels; and group III, men with functional anorchia (n = 3) receiving testosterone replacement. DESIGN: Subjects were studied before and after 3 d of acute sex steroid withdrawal. SETTING: The study was conducted at the Mallinckrodt General Clinical Research Center of Massachusetts General Hospital. INTERVENTIONS: Acute biochemical castration was achieved using high-dose ketoconazole (groups I and II) or withdrawal of androgen therapy (group III). MAIN OUTCOME MEASURES: The relationship between FSH and inhibin B in both normal and castrate sex steroid milieu was measured. RESULTS: In both normal and castrate sex steroid milieus, there was a negative relationship between inhibin B and FSH, best described by a logarithmic model. Acute biochemical castration resulted in the most dramatic increases in FSH in men with the lowest baseline inhibin B levels. CONCLUSIONS: We came to the following conclusions: 1) in the human male, inhibin B is the principal gonadal feedback regulator of FSH secretion unless seminiferous tubular function is severely compromised, and a logarithmic model best describes this relationship; and 2) sex steroid inhibition of FSH secretion is most apparent when serum inhibin B levels fall well below the normal range.


Assuntos
Hormônio Foliculoestimulante/sangue , Hormônios Esteroides Gonadais/fisiologia , Inibinas/fisiologia , Epitélio Seminífero/fisiologia , Adulto , Retroalimentação Fisiológica , Humanos , Inibinas/sangue , Masculino , Pessoa de Meia-Idade
16.
J Clin Endocrinol Metab ; 93(7): 2686-92, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18445673

RESUMO

OBJECTIVE: Our objective was to determine the importance of testosterone (T), estradiol (E(2)), and GnRH pulse frequency to FSH regulation in men. DESIGN: This was a prospective study with four arms. SETTING: The study was performed at the General Clinical Research Center. PATIENTS OR OTHER PARTICIPANTS: There were 20 normal (NL) men and 15 men with idiopathic hypogonadotropic hypogonadism (IHH) who completed the study. INTERVENTION: Medical castration and inhibition of aromatase were achieved using ketoconazole x 7 d with: 1) no sex steroid addback, 2) T addback starting on d 4, and 3) E(2) addback starting on d 4. IHH men in these arms received GnRH every 120 min. In a further six IHH men receiving ketoconazole with no addback, GnRH frequency was increased to 35 min for d 4-7. Blood was drawn every 10 min x 12 h at baseline, overnight on d 3-4 and 6-7. MAIN OUTCOME MEASURES: Mean FSH was calculated from the pool of each frequent sampling study. RESULTS: In NL men FSH levels increased from 5.1 +/- 0.7 to 8.7 +/- 1.3 and 9.7 +/- 1.5 IU/liter (P < 0.0001). T caused no suppression of FSH. E(2) reduced FSH from 12.4 +/- 1.8 to 9.3 +/- 1.3 IU/liter (P < 0.05). In IHH men on GnRH every 120 min, FSH levels went from 6.0 +/- 1.6 to 9.0 +/- 3.0 and 11.9 +/- 4.3 (P = 0.07). T caused no suppression of FSH. E(2) decreased FSH such that levels on d 6-7 were similar to baseline. Increasing GnRH frequency to 35 min had no impact on FSH. CONCLUSIONS: The sex steroid component of FSH negative feedback in men is mediated by E(2). Increasing GnRH frequency to castrate levels has no impact on FSH in the absence of sex steroids. When inhibin B levels are NL, sex steroids exert a modest effect on FSH.


Assuntos
Estradiol/fisiologia , Hormônio Foliculoestimulante/metabolismo , Hormônio Liberador de Gonadotropina/fisiologia , Testosterona/fisiologia , Adulto , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/deficiência , Humanos , Hormônio Luteinizante/sangue , Masculino , Estudos Prospectivos
17.
J Clin Endocrinol Metab ; 93(9): 3551-9, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18559922

RESUMO

CONTEXT: Mice deficient in prokineticin 2(PROK2) and prokineticin receptor2 (PROKR2) exhibit variable olfactory bulb dysgenesis and GnRH neuronal migration defects reminiscent of human GnRH deficiency. OBJECTIVES: We aimed to screen a large cohort of patients with Kallmann syndrome (KS) and normosmic idiopathic hypogonadotropic hypogonadism (IHH) for mutations in PROK2/PROKR2, evaluate their prevalence, define the genotype/phenotype relationship, and assess the functionality of these mutant alleles in vitro. DESIGN: Sequencing of the PROK2 and PROKR2 genes was performed in 170 KS patients and 154 nIHH. Mutations were examined using early growth response 1-luciferase assays in HEK 293 cells and aequorin assays in Chinese hamster ovary cells. RESULTS: Four heterozygous and one homozygous PROK2 mutation (p.A24P, p.C34Y, p.I50M, p.R73C, and p.I55fsX1) were identified in five probands. Four probands had KS and one nIHH, and all had absent puberty. Each mutant peptide impaired receptor signaling in vitro except the I50M. There were 11 patients who carried a heterozygous PROKR2 mutation (p.R85C, p.Y113H, p.V115M, p.R164Q, p.L173R, p.W178S, p.S188L, p.R248Q, p.V331M, and p.R357W). Among them, six had KS, four nIHH, and one KS proband carried both a PROKR2 (p.V115M) and PROK2 (p.A24P) mutation. Reproductive phenotypes ranged from absent to partial puberty to complete reversal of GnRH deficiency after discontinuation of therapy. All mutant alleles appear to decrease intracellular calcium mobilization; seven exhibited decreased MAPK signaling, and six displayed decreased receptor expression. Nonreproductive phenotypes included fibrous dysplasia, sleep disorder, synkinesia, and epilepsy. Finally, considerable variability was evident in family members with the same mutation, including asymptomatic carriers. CONCLUSION: Loss-of-function mutations in PROK2 and PROKR2 underlie both KS and nIHH.


Assuntos
Hormônios Gastrointestinais/genética , Hormônio Liberador de Gonadotropina/deficiência , Hipogonadismo/genética , Mutação de Sentido Incorreto , Neuropeptídeos/genética , Receptores Acoplados a Proteínas G/genética , Receptores de Peptídeos/genética , Adolescente , Equorina/genética , Animais , Células CHO , Cricetinae , Cricetulus , Análise Mutacional de DNA , Feminino , Frequência do Gene , Heterogeneidade Genética , Genótipo , Humanos , Síndrome de Kallmann/genética , Masculino , Modelos Biológicos , Linhagem , Transfecção
18.
Ann N Y Acad Sci ; 1135: 219-29, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18574228

RESUMO

Epilepsy, bipolar disorder, and migraines are common disorders that are often associated with disturbances in menstrual function in adolescent girls. Women with untreated epilepsy are more likely to have irregular menstrual cycles than are nonepileptic controls, indicating that the disease itself plays a role in the etiology of these reproductive abnormalities. In addition, many girls with these disorders require chronic maintenance treatment with agents that may perturb the hypothalamic-pituitary-ovarian axis. Valproate is a highly effective antiepileptic drug used widely to treat epilepsy, bipolar disorder, and migraines. Valproate induces features of the polycystic ovary syndrome (PCOS) in approximately 7% of women. Girls with epilepsy, and possibly bipolar disorder, appear particularly susceptible to developing PCOS features on valproate, perhaps on account of the relative immaturity of their hypothalamic-pituitary-ovarian axes. Antipsychotics are highly effective drugs used widely to treat adolescents with bipolar disorder, psychotic disorders, and behavioral disturbances. Some, but not all of the antipsychotic, induce hyperprolactinemia, which may result in oligo- or amenorrhea. Prolonged amenorrhea in association with hyperprolactinemia incurs significant risks for bone health in adolescent girls. Because of the potential reproductive health risks associated with use of specific antiepileptic drugs and selective antipsychotics, these agents are vital treatments for adolescents with severe illnesses. Use of these agents should be considered and weighed against the risk of using alternative agents, which have their own side effects, or not treating these serious neurologic and psychiatric disorders.


Assuntos
Transtorno Bipolar/complicações , Epilepsia/complicações , Ciclo Menstrual , Transtornos de Enxaqueca/complicações , Adolescente , Amenorreia/etiologia , Anticonvulsivantes/efeitos adversos , Antipsicóticos/efeitos adversos , Osso e Ossos/efeitos dos fármacos , Feminino , Humanos , Hiperprolactinemia/etiologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Síndrome do Ovário Policístico/etiologia , Fatores de Risco , Ácido Valproico/efeitos adversos
19.
Clin Chim Acta ; 388(1-2): 99-105, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18023274

RESUMO

BACKGROUND: Measurement of estradiol (E(2)) plays a critical role in the diagnosis and clinical management of reproductive disorders. The challenge for all currently available direct methods for measuring E(2) is to provide accuracy and precision across a wide dynamic range. METHODS: We describe the development and multi-site performance evaluation of a direct E(2) assay on the Architect i2000. Assay performance and method comparisons were performed by testing specimens from men, healthy women with regular menstrual cycles, and post-menopausal women using the Architect assay and isotope dilution, gas chromatography-mass spectrometry (ID/GC-MS). Reference intervals were established by testing prospectively collected daily blood draws from 42 healthy women, 72 postmenopausal women and 101 males. RESULTS: No unexpected cross-reactivity or interference was observed for over 40 compounds tested. Recovery was 100+/-10% in the presence of estrone and estriol. Functional sensitivity (%CV<20%) was <15 pg/ml.(1) The imprecision of the assay was <7.1% (total CV), <2.5%, and <2.3% for control sera containing 45, 190, and 600 pg/ml estradiol, respectively. The assay had a correlation of y=1.033 x+0.3156, r(2)=0.99, n=131 compared to ID/GC-MS. Reference intervals for the current Architect Estradiol assay are reported. CONCLUSIONS: Format changes resulted in dramatic improvement in the performance and accuracy of this direct, fully automated assay. The assay is standardized by ID/GC-MS. The assay is clinically useful for serum concentrations from 15 to >4000 pg/ml.


Assuntos
Estradiol/sangue , Estradiol/imunologia , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Imunoensaio/instrumentação , Imunoensaio/métodos , Adolescente , Adulto , Estradiol/química , Estriol/sangue , Estrona/sangue , Feminino , Humanos , Ciclo Menstrual/sangue , Sensibilidade e Especificidade
20.
J Clin Endocrinol Metab ; 103(5): 1715-1744, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29562364

RESUMO

Objective: To update the "Testosterone Therapy in Men With Androgen Deficiency Syndromes" guideline published in 2010. Participants: The participants include an Endocrine Society-appointed task force of 10 medical content experts and a clinical practice guideline methodologist. Evidence: This evidence-based guideline was developed using the Grading of Recommendations, Assessment, Development, and Evaluation approach to describe the strength of recommendations and the quality of evidence. The task force commissioned two systematic reviews and used the best available evidence from other published systematic reviews and individual studies. Consensus Process: One group meeting, several conference calls, and e-mail communications facilitated consensus development. Endocrine Society committees and members and the cosponsoring organization were invited to review and comment on preliminary drafts of the guideline. Conclusions: We recommend making a diagnosis of hypogonadism only in men with symptoms and signs consistent with testosterone (T) deficiency and unequivocally and consistently low serum T concentrations. We recommend measuring fasting morning total T concentrations using an accurate and reliable assay as the initial diagnostic test. We recommend confirming the diagnosis by repeating the measurement of morning fasting total T concentrations. In men whose total T is near the lower limit of normal or who have a condition that alters sex hormone-binding globulin, we recommend obtaining a free T concentration using either equilibrium dialysis or estimating it using an accurate formula. In men determined to have androgen deficiency, we recommend additional diagnostic evaluation to ascertain the cause of androgen deficiency. We recommend T therapy for men with symptomatic T deficiency to induce and maintain secondary sex characteristics and correct symptoms of hypogonadism after discussing the potential benefits and risks of therapy and of monitoring therapy and involving the patient in decision making. We recommend against starting T therapy in patients who are planning fertility in the near term or have any of the following conditions: breast or prostate cancer, a palpable prostate nodule or induration, prostate-specific antigen level > 4 ng/mL, prostate-specific antigen > 3 ng/mL in men at increased risk of prostate cancer (e.g., African Americans and men with a first-degree relative with diagnosed prostate cancer) without further urological evaluation, elevated hematocrit, untreated severe obstructive sleep apnea, severe lower urinary tract symptoms, uncontrolled heart failure, myocardial infarction or stroke within the last 6 months, or thrombophilia. We suggest that when clinicians institute T therapy, they aim at achieving T concentrations in the mid-normal range during treatment with any of the approved formulations, taking into consideration patient preference, pharmacokinetics, formulation-specific adverse effects, treatment burden, and cost. Clinicians should monitor men receiving T therapy using a standardized plan that includes: evaluating symptoms, adverse effects, and compliance; measuring serum T and hematocrit concentrations; and evaluating prostate cancer risk during the first year after initiating T therapy.


Assuntos
Endocrinologia/normas , Terapia de Reposição Hormonal/normas , Hipogonadismo/tratamento farmacológico , Testosterona/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/sangue , Análise Química do Sangue/métodos , Análise Química do Sangue/normas , Consenso , Técnicas de Diagnóstico Endócrino/normas , Endocrinologia/métodos , Endocrinologia/tendências , Medicina Baseada em Evidências , Terapia de Reposição Hormonal/métodos , Humanos , Hipogonadismo/sangue , Hipogonadismo/diagnóstico , Masculino , Pessoa de Meia-Idade , Sociedades Médicas/organização & administração , Sociedades Médicas/normas , Testosterona/sangue , Testosterona/deficiência
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