RESUMO
La diferenciación sexual es un proceso genéticamente determinado y controlado, que puede ser alterado por diferentes tipos de mutaciones genéticas, o por el efecto de hormonas u otros disruptores ambientales que actúan sobre el embrión, resultando en genitales externos ambiguos en el recién nacido. Se revisa la diferenciación sexual normal y se presenta la nueva clasificación propuesta para los desórdenes del desarrollo sexual. Se mencionaron los aspectos clínicos, el uso de imágenes y los estudios genéticos y hormonales para el diagnóstico. Se discute sobre los diferentes elementos que deben ser considerados para la asignación de sexo.
Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Diferenciação Sexual/genética , Genitália/anormalidades , Transtornos do Desenvolvimento Sexual/genética , Fatores SexuaisRESUMO
BACKGROUND: Precocious puberty may reduce final adult height, and affected children may suffer social and emotional problems. The efficacy of treatment with a long acting agonist analogue of the gonadotropin releasing hormone (aLHRH) has been well demonstrated. AIM: To evaluated the efficacy of a new formulation of aLHRH (leuprolide, Lupron) for the suppression of gonadotropin activation and clinical signs of puberty. MATERIAL AND METHODS: Eleven children (ten females) with idiopathic central precocious puberty, with a mean chronological age of 7.5+/-1.8 years and a bone age of 9.7+/-1.8 years were recruited. Testicular volume in the male was 15 ml. In females, Tanner stage for breast development was between 2-4 and mean ovarian volume was 2.3+/-0.8 ml. They were treated during 18 months with aLHRH, 11.25 mg administered intramuscularly every three months. RESULTS: Clinical, hormonal and ultrasonographic signs of puberty regressed in all patients. The degree of suppression of LH was 87.7+/-5.1% at the end of the 18 months. No significant changes in bone mineral content were observed during the treatment period. CONCLUSIONS: Leuprolide (aLHRH) 11.25 mg, injected every three months, is effective for the control of central precocious puberty and allows to reduce the number of yearly injections from 12 to 4.
Assuntos
Desenvolvimento Ósseo/efeitos dos fármacos , Fármacos para a Fertilidade/administração & dosagem , Hormônio Liberador de Gonadotropina/metabolismo , Leuprolida/administração & dosagem , Hormônio Luteinizante/agonistas , Puberdade Precoce/tratamento farmacológico , Determinação da Idade pelo Esqueleto , Estatura , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Desenvolvimento Ósseo/fisiologia , Mama/efeitos dos fármacos , Mama/crescimento & desenvolvimento , Criança , Feminino , Humanos , Injeções Intramusculares , Hormônio Luteinizante/sangue , Masculino , Ovário/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testosterona/sangueRESUMO
Background: Precocious puberty may reduce final adult height, and affected children may suffer social and emotional problems. The efficacy of treatment with a long acting agonist analogue of the gonadotropin releasing hormone (aLHRH) has been well demonstrated. Aim: To evaluated the efficacy of a new formulation of aLHRH (leuprolide, Lupron ®) for the suppression of gonadotropin activation and clinical signs of puberty. Material and methods: Eleven children (ten females) with idiopathic central precocious puberty, with a mean chronological age of 7.5±1.8 years and a bone age of 9.7±1.8 years were recruited. Testicular volume in the male was 15 ml. In females, Tanner stage for breast development was between 2-4 and mean ovarian volume was 2.3±0.8 ml. They were treated during 18 months with aLHRH, 11.25 mg administered intramuscularly every three months. Results: Clinical, hormonal and ultrasonographic signs of puberty regressed in all patients. The degree of suppression of LH was 87.7±5.1% at the end of the 18 months. No significant changes in bone mineral content were observed during the treatment period. Conclusions: Leuprolide (aLHRH) 11.25 mg, injected every three months, is effective for the control of central precocious puberty and allows to reduce the number of yearly injections from 12 to 4.
Assuntos
Criança , Feminino , Humanos , Masculino , Desenvolvimento Ósseo/efeitos dos fármacos , Fármacos para a Fertilidade/administração & dosagem , Hormônio Liberador de Gonadotropina/metabolismo , Leuprolida/administração & dosagem , Hormônio Luteinizante/agonistas , Puberdade Precoce/tratamento farmacológico , Determinação da Idade pelo Esqueleto , Estatura , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Desenvolvimento Ósseo/fisiologia , Mama/efeitos dos fármacos , Mama/crescimento & desenvolvimento , Injeções Intramusculares , Hormônio Luteinizante/sangue , Ovário/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testosterona/sangueRESUMO
La obesidad infantil ha aumentado en Chile y con ella sus riesgos a largo plazo. Objetivo: Determinar la prevalencia de sobrepeso (SP) y obesidad (O) en niños controlados en un centro privado en Chile (Clínica Las Condes = CLC). Pacientes y Métodos: Estudio prospectivo en un año de 1.310 niños entre 2 y 18 años (51,6 por ciento hombres) de 7,19 ± 4,02 años de edad promedio. Se consignó edad, sexo, antropometría, y se calculó Índice de Masa Corporal (IMC, kg/m2) absoluto y percentil (p) y el porcentaje peso/talla ( por ciento P/T). Resultados: Los pacientes se distribuyeron en 3 grupos etarios: 45,7 por ciento entre 2-5, 29,5 por ciento entre 6-10 y 24,8 por ciento >10 años. Un 66,8 por ciento estaba eutrófico (IMC p10-85), SP 13,9 por ciento (IMC p85-95), O 12 por ciento (IMC > p95) y bajo peso (BP) 7,3 por ciento (IMC < p10), sin diferencias según sexo ni grupo etario. Conclusiones: La prevalencia de BP, SP y O en CLC es similar a la observada en niveles socioeconómicos medio-bajos chilenos. La mayor proporción entre 6-10 años hace indispensable su prevención desde la etapa de lactante.
Assuntos
Masculino , Adolescente , Humanos , Feminino , Pré-Escolar , Criança , Obesidade/epidemiologia , Distribuição por Idade , Assistência Ambulatorial , Estatura , Índice de Massa Corporal , Peso Corporal , Chile/epidemiologia , Prevalência , Estudos Prospectivos , Distribuição por SexoRESUMO
The beginning of puberty is marked by breast growth in girls and testicular enlargement in boys. These occur at the age of 10.5 ñ 2.0 years in females and 11.5 ñ 2.0 years in males. Recent but controversial publications suggest that these events are being observed at younger ages, at least in the USA. There are no studies demonstrating that this is true in Chile. For this reason we still consider that puberty is precocious when it occurs before 8.0 years in girls and before 9.0 years in boys. True or central precocious puberty (CPP) must be distinguished from peripheral or pseudoprecocious puberty (PPP), from premature telarche and from premature adrenarche. We suggest that the workup of a patient with premature development should include an LHRH test to demonstrate if the hypothalamic-pituitary axis is activated, plasma levels of sex steroids, bone age and pelvic ultrasound in girls. All children with CPP should have a CAT scan or MNR of the brain, since a lesion of the central nervous system is observed in 15 percent of the girls and 50 percent of the boys whith CPP. Additional studies are needed in cases of PPP. The aim of treating CPP is to avoid adult short stature that results from premature fusion of the epiphysis and to avoid eventual emotional and psychological stress. Treatment consists of monthly intramuscular injections of a depot preparation of LHRH analogs. Suppression of pituitary and gonadal activity produces regression of secondary sex characteristics and slowing down of growth velocity and bone maturation. The opportunity, duration of treatment and their effect on final stature are discussed
Assuntos
Humanos , Masculino , Feminino , Puberdade Precoce , Hormônio Liberador de Gonadotropina , Transtornos do Crescimento , Hormônios Esteroides Gonadais/sangue , Sistema Hipotálamo-Hipofisário/fisiopatologiaRESUMO
Background: Short stature is the main feature of patients with Turner's syndrome. There is limited information regarding the spontaneous growth of these patients in Chile. Aim: To develop a specific growth chart for Chilean patients with Turner's syndrome. Material and methods: We retrospectively analyzed 668 height measurements from 85 Chilean girls, born after 1968, with 45XO karyotype (minimum 15 percent), and without an Y chromosome fragment. Patients with hormonal therapy, such as growth hormone or estrogen, except thyroid hormone replacement, were excluded. Results: The karyotypes were 60 percent 45XO, 25 percent 45XO, 46XX, and 15 percent other complex mosaics. The birth length was 46.8 ñ 2.1 cm. The final height of our patients was 138,20 ñ 7,0 cm. Conclusions: The final height achieved by our patients, is similar to Argentinian and Japanese patients, but is below the mean stature reported for Scandinavian and Northamerican patients who achieve a mean adult height of approximately 147 and 142 cm respectively. The birth length is also lower than that reported in those studies
Assuntos
Humanos , Adolescente , Feminino , Lactente , Pré-Escolar , Transtornos do Crescimento , Síndrome de Turner/fisiopatologia , Síndrome de Turner/complicações , Síndrome de Turner/etnologiaRESUMO
Prader-Willi syndrome (PWS) is a neurogenetic disorder caused by the absence or abnormal inactivation of a critical region of the paternal chromosome 15. Clinical manifestations include marked hypotonia at birth, progressive obesity that starts during the second year of life, stunting, hypogonadism and some dysmorphic features. Some of the symptoms and signs can be explained by growth hormone (GH) deficiency. We report two females aged 12 and 13 years old with PWS. Both were very short and obese, showed blunted GH responses to provocative stimuli and had low plasma levels of Insulin Growth Factor-1 (IGF-1). They have been on GH treatment for more than two years, demonstrating a marked growth acceleration, reduction in their fat mass, improvement of their muscular strength and an increase in their IGF-1 levels
Assuntos
Humanos , Adolescente , Feminino , Hormônio do Crescimento Humano , Síndrome de Prader-Willi/tratamento farmacológicoRESUMO
Background: Medullary thyroid carcinoma (MTC) may occur either as a sporadic or familial disease. Multiple endocrine neoplasia (MEN) type 2, inherited as an autosomal dominant disease, is characterized by MTC only (FMTC) or coexistence of MTC with other endocrine neoplasia (NEM 2A, 2B). Germline mutations of the RET proto-oncogene (cRet) are found in the inherited forms and in some apparently sporadic MTC cases. Aim: To study RET mutations in 8 families with MEN 2. Material and methods: RET mutations were screened in peripheral blood DNA from 18 patients and 87 high risk carriers belonging to 8 MEN 2 families and 52 sporadic MTC. Exons 10, 11, 13, 14, 15 and 16 of the c-Ret were amplified by polymerase chain reaction (PCR) and examined by direct sequencing of PCR products and/or restriction enzyme analysis. Results: Five MEN 2A and one FMTC families with a germline mutation at codon 634, one MEN 2A and one FMTC family carrying a mutation at codon 620 were identified. Mutations were found in 23 out of 87 high risk carriers. In addition, we detected a S891A (exon 15) germline mutation in a sporadic MTC patient and in one out of her three sons and V804M (exon 14) in another sporadic MTC case and in one out of his six relatives, indicating in both cases the presence of a sporadic misclassified familial disease. Conclusions: These results underscore the importance of routine application of c-Ret testing in all cases of MTC either familial or sporadic