RESUMEN
Recombinant human GH (rhGH) has been in use for 30 years, and over that time its safety and efficacy in children and adults has been subject to considerable scrutiny. In 2001, a statement from the GH Research Society (GRS) concluded that 'for approved indications, GH is safe'; however, the statement highlighted a number of areas for on-going surveillance of long-term safety, including cancer risk, impact on glucose homeostasis, and use of high dose pharmacological rhGH treatment. Over the intervening years, there have been a number of publications addressing the safety of rhGH with regard to mortality, cancer and cardiovascular risk, and the need for long-term surveillance of the increasing number of adults who were treated with rhGH in childhood. Against this backdrop of interest in safety, the European Society of Paediatric Endocrinology (ESPE), the GRS, and the Pediatric Endocrine Society (PES) convened a meeting to reappraise the safety of rhGH. The ouput of the meeting is a concise position statement.
Asunto(s)
Consenso , Hormona de Crecimiento Humana/efectos adversos , Seguridad del Paciente/normas , Sociedades Médicas/normas , Adulto , Niño , Educación , Endocrinología/normas , Europa (Continente) , Humanos , Pediatría/normas , Proteínas RecombinantesRESUMEN
Defects in the growth hormone (GH)-insulin-like growth factor (IGF)I axis may cause GH resistance characterized by IGFI deficiency and growth failure. The range of defects causing GH resistance is broad as are their biochemical and phenotypical characteristics. We propose that GH-IGFI axis defects form a continuum of clinical and biochemical effects ranging from GH deficiency to GH resistance. The pathophysiology of GH resistance is described followed by a scheme for investigation of the child with severe short stature and normal GH secretion. We critically discuss GH therapy for such patients and define acceptable growth responsiveness. Finally we discuss therapy with IGF-I within the limits of the USA Food and Drug Administration and European Medicines Agency labels for GH resistance.
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Trastornos del Crecimiento/fisiopatología , Trastornos del Crecimiento/terapia , Animales , Niño , Trastornos del Crecimiento/genética , Terapia de Reemplazo de Hormonas/métodos , Hormona de Crecimiento Humana/fisiología , Humanos , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/fisiología , Factor I del Crecimiento Similar a la Insulina/uso terapéutico , Receptores de Somatotropina/genética , Receptores de Somatotropina/fisiologíaRESUMEN
BACKGROUND: Growth hormone (GH) is a therapeutic option for small for gestational age (SGA) children without spontaneous catch-up. There are few reports on preterm SGA children. Prematurity is an additional risk factor for adult short stature. AIM: To describe GH efficacy in preterm SGA patients. METHODS: Twenty-five preterm SGA patients, 2-4 years old, treated with GH 0.066 mg/kg/day, were compared with 14 age-matched preterm SGA historical controls. Height, weight, IGF-I, IGFBP-3, fasting glucose and insulin were measured every 6 months. RESULTS: At start of GH treatment, mean height and weight were -2.4 and -2.4 SDS, respectively. There was a significant increment in height SDS of 1.3 and 2.1 during the 1st and the 2nd year of GH therapy, respectively. There was no significant difference between the progression of chronological and bone ages. A significant increase in IGF-I, IGFBP-3 and molar ratio was observed during GH therapy. There was no difference in glucose, insulin or HOMA-IR index. CONCLUSION: We showed for the first time that the height increment of preterm SGA with GH treatment is similar to that described in other studies with term SGA patients. Therefore, short-term GH treatment in a subset of preterm SGA patients between 2-4 years of age was able to promote adequate growth recovery with no excessive bone age acceleration or adverse effects on carbohydrate metabolism.
Asunto(s)
Trastornos del Crecimiento/tratamiento farmacológico , Hormona de Crecimiento Humana/uso terapéutico , Recien Nacido Prematuro/crecimiento & desarrollo , Recién Nacido Pequeño para la Edad Gestacional/crecimiento & desarrollo , Determinación de la Edad por el Esqueleto , Estatura/efectos de los fármacos , Índice de Masa Corporal , Preescolar , Estudios de Seguimiento , Trastornos del Crecimiento/sangre , Trastornos del Crecimiento/fisiopatología , Hormona de Crecimiento Humana/sangre , Humanos , Lactante , Recién Nacido , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Proteínas Recombinantes/uso terapéuticoRESUMEN
AIM: This phase III clinical study in growth hormone deficiency (GHD) children with growth retardation was designed to compare efficacy and safety of Omnitrope((R)) with Genotropin((R)) and assess the long-term safety and efficacy of Omnitrope((R)). The results of 7 years of treatment with Omnitrope((R)) are presented. PATIENTS AND METHODS: Eighty-nine treatment-naïve, prepubertal children with GHD were randomized (part 1) to Omnitrope((R)) lyophilisate (group A, n = 44) or Genotropin((R)) (group B, n = 45) for 9 months and received a subcutaneous dose of 0.03 mg/kg/day. In part 2, patients receiving Omnitrope((R))lyophilisate continued the same treatment for a further 6 months, while patients on Genotropin((R)) were switched to Omnitrope((R)) liquid for the subsequent 6 months. In part 3, patients in both groups received Omnitrope((R))liquid for a period up to 69 months. RESULTS: The development of the 4 auxological parameters (height, height SD score, height velocity and height velocity SD score) and IGF-1 and IGFBP-3 levels were comparable between both groups of patients and confirmed the well-known growth response of GHD children to recombinant human GH treatment. Omnitrope((R)) was well tolerated and safe over 7 years of treatment. CONCLUSION: The clinical comparability between Omnitrope((R)) and Genotropin((R)) was demonstrated within 9 months of treatment. Long-term safety and efficacy of 7 years of treatment with Omnitrope((R)) was proven.
Asunto(s)
Trastornos del Crecimiento/tratamiento farmacológico , Hormona de Crecimiento Humana/deficiencia , Hormona de Crecimiento Humana/uso terapéutico , Adolescente , Estatura/efectos de los fármacos , Niño , Preescolar , Femenino , Trastornos del Crecimiento/sangre , Trastornos del Crecimiento/patología , Hormona de Crecimiento Humana/administración & dosificación , Hormona de Crecimiento Humana/efectos adversos , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéutico , Resultado del Tratamiento , Aumento de Peso/efectos de los fármacosRESUMEN
OBJECTIVE: Our objective was to summarize important advances in the management of children with idiopathic short stature (ISS). PARTICIPANTS: Participants were 32 invited leaders in the field. EVIDENCE: Evidence was obtained by extensive literature review and from clinical experience. CONSENSUS: Participants reviewed discussion summaries, voted, and reached a majority decision on each document section. CONCLUSIONS: ISS is defined auxologically by a height below -2 sd score (SDS) without findings of disease as evident by a complete evaluation by a pediatric endocrinologist including stimulated GH levels. Magnetic resonance imaging is not necessary in patients with ISS. ISS may be a risk factor for psychosocial problems, but true psychopathology is rare. In the United States and seven other countries, the regulatory authorities approved GH treatment (at doses up to 53 microg/kg.d) for children shorter than -2.25 SDS, whereas in other countries, lower cutoffs are proposed. Aromatase inhibition increases predicted adult height in males with ISS, but adult-height data are not available. Psychological counseling is worthwhile to consider instead of or as an adjunct to hormone treatment. The predicted height may be inaccurate and is not an absolute criterion for GH treatment decisions. The shorter the child, the more consideration should be given to GH. Successful first-year response to GH treatment includes an increase in height SDS of more than 0.3-0.5. The mean increase in adult height in children with ISS attributable to GH therapy (average duration of 4-7 yr) is 3.5-7.5 cm. Responses are highly variable. IGF-I levels may be helpful in assessing compliance and GH sensitivity; levels that are consistently elevated (>2.5 SDS) should prompt consideration of GH dose reduction. GH therapy for children with ISS has a similar safety profile to other GH indications.
Asunto(s)
Trastornos del Crecimiento/diagnóstico , Trastornos del Crecimiento/terapia , Adulto , Estatura , Peso Corporal , Niño , Endocrinología/métodos , Femenino , Hormona Liberadora de Gonadotropina/uso terapéutico , Trastornos del Crecimiento/clasificación , Trastornos del Crecimiento/psicología , Humanos , Factor I del Crecimiento Similar a la Insulina/deficiencia , Masculino , Tamizaje Masivo , Valores de ReferenciaRESUMEN
In the management of ISS auxological, biochemical, psychosocial and ethical elements have to be considered. In boys with constitutional delay of growth and puberty androgens are effective in increasing height and sexual characteristics, but adult height is unchanged. GH therapy is efficacious in increasing height velocity and adult height, but the inter-individual variation is considerable. The effect on psychosocial status is uncertain. Factors affecting final height gain include GH dose, height deficit in comparison to midparental height, age and first year height velocity. In case of a low predicted adult height at the onset of puberty, addition of a GnRH analogue can be considered. Although GH therapy appears safe, long-term monitoring is recommended.
Asunto(s)
Trastornos del Crecimiento/tratamiento farmacológico , Hormona de Crecimiento Humana/uso terapéutico , Determinación de la Edad por el Esqueleto , Composición Corporal , Estatura/efectos de los fármacos , Ensayos Clínicos como Asunto/ética , Ensayos Clínicos como Asunto/tendencias , Consejo , Trastornos del Crecimiento/diagnóstico , Trastornos del Crecimiento/psicología , Hormona de Crecimiento Humana/efectos adversos , Humanos , Pubertad/efectos de los fármacos , Pubertad/fisiología , Calidad de Vida , Resultado del TratamientoRESUMEN
Idiopathic short stature is a condition in which the height of the individual is more than 2 SD below the corresponding mean height for a given age, sex and population, in whom no identifiable disorder is present. It can be subcategorized into familial and non-familial ISS, and according to pubertal delay. It should be differentiated from dysmorphic syndromes, skeletal dysplasias, short stature secondary to a small birth size (small for gestational age, SGA), and systemic and endocrine diseases. ISS is the diagnostic group that remains after excluding known conditions in short children.
Asunto(s)
Trastornos del Crecimiento/diagnóstico , Trastornos del Crecimiento/epidemiología , Estatura/fisiología , Técnicas de Diagnóstico Endocrino , Trastornos del Crecimiento/etiología , Trastornos del Crecimiento/genética , Humanos , Técnicas de Diagnóstico MolecularRESUMEN
We report 24-month interim results of two multicenter phase III studies in previously untreated children with growth failure secondary to GH deficiency (GHD) that were paramount to the development of a new recombinant human GH (rh- GH, somatropin), approved as the first 'biosimilar' in Europe. Study 1 consisted of 3 parts performed in 89 children. The objective was to compare efficacy and safety of the lyophilized formulation of the new somatropin [Somatropin Powder (Sandoz)] with a licensed reference rhGH preparation and the liquid formulation of the new somatropin [Somatropin Solution (Sandoz)] and to assess long-term efficacy and safety of this ready-to-use Somatropin Solution. Study 2 was performed in 51 children and designed to demonstrate efficacy and safety of Somatropin Powder and to confirm its low immunogenic potential; rhGH was given sc at a daily dose of 0.03 mg/kg. Primary [body height, height SD score (HSDS), height velocity, and height velocity (HV) SD score (HVSDS)] and secondary [IGF-I and IGF binding protein 3 (IGFBP-3)] efficacy endpoints and safety parameters were assessed regularly. In study 1, all treatments showed comparable increases in growth. The baseline-adjusted difference between Somatropin Powder and the reference rhGH product in mean HV was -0.20 cm/yr (95% confidence interval (CI) [-1.34;0.94]) and in mean HVSDS was 0.76 (95% CI [-0.57;2.10]) after 9 months. These very small differences demonstrate comparable therapeutic efficacy between the two treatments. The results of study 2 were consistent with those seen in study 1. Equivalent therapeutic efficacy and clinical comparability in terms of safety and immunogenicity between Somatropin Powder and the reference rhGH product and between Somatropin Powder and Somatropin Solution was demonstrated. The safety and immunogenicity profiles were similar and as expected from experience with rhGH preparations.
Asunto(s)
Trastornos del Crecimiento/tratamiento farmacológico , Hormona de Crecimiento Humana/administración & dosificación , Determinación de la Edad por el Esqueleto , Estatura/efectos de los fármacos , Niño , Preescolar , Femenino , Estudios de Seguimiento , Hormona de Crecimiento Humana/efectos adversos , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Masculino , Polvos , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Soluciones , Resultado del TratamientoRESUMEN
Understanding the genetic composition and mating systems of edge populations provides important insights into the environmental and demographic factors shaping species' distribution ranges. We analysed samples of the mangrove Avicennia marina from Vietnam, northern Philippines and Australia, with microsatellite markers. We compared genetic diversity and structure in edge (Southeast Asia, and Southern Australia) and core (North and Eastern Australia) populations, and also compared our results with previously published data from core and southern edge populations. Comparisons highlighted significantly reduced gene diversity and higher genetic structure in both margins compared to core populations, which can be attributed to very low effective population size, pollinator scarcity and high environmental pressure at distribution margins. The estimated level of inbreeding was significantly higher in northeastern populations compared to core and southern populations. This suggests that despite the high genetic load usually associated with inbreeding, inbreeding or even selfing may be advantageous in margin habitats due to the possible advantages of reproductive assurance, or local adaptation. The very high level of genetic structure and inbreeding show that populations of A. marina are functioning as independent evolutionary units more than as components of a metapopulation system connected by gene flow. The combinations of those characteristics make these peripheral populations likely to develop local adaptations and therefore to be of particular interest for conservation strategies as well as for adaptation to possible future environmental changes.
Asunto(s)
Avicennia/genética , Biodiversidad , Endogamia , Australia , Avicennia/fisiología , Flujo Génico , Variación Genética , Geografía , Desequilibrio de Ligamiento , Repeticiones de Microsatélite , Filipinas , VietnamRESUMEN
BACKGROUND: Recently, growth hormone (GH) therapy for children with short stature born small for gestational age (SGA) has been approved in the USA and Europe. There have been few reports examining adverse events during GH treatment of these children. AIMS: (i) To examine glucose tolerance and insulin sensitivity during GH treatment of children born SGA in a US trial. (ii) To determine and compare adverse events reported in children born SGA with those reported in children with idiopathic short stature (ISS) enrolled in KIGS - Pfizer International Growth Database. METHODS: In the US SGA trial, an oral glucose tolerance test was performed and fasting plasma glucose, insulin and glycosylated haemoglobin (HbA(1C)) concentrations were measured at baseline and after 12 months of GH therapy. Insulin sensitivity was calculated using the homeostasis model assessment (HOMA) and the quantitative insulin sensitivity check index (QUICKI). In the KIGS analysis, a retrospective audit of spontaneously logged cumulative adverse events in children born SGA and those with ISS was undertaken. Adverse events are reported per 1,000 patients. Values are expressed as mean with 10th-90th percentiles. RESULTS: In the US trial, 84 patients had complete data sets for analysis. Median birth weight was 1.78 kg (SDS, -2.5) and birth length 43 cm (SDS, -2.2) at a median gestational age of 36.5 weeks; 79% were Caucasian. At entry, median age of the patients analysed was 6.6 years, and 65% were male. Median height was 104.3 cm (SDS, -2.97), median weight 15.95 kg (SDS, -2.21) and body mass index 14.66 kg/m(2) (SDS, -0.67). No patients developed impaired glucose tolerance or overt diabetes mellitus. The 0-min glucose concentration was 81 mg/dl at baseline and 86 mg/dl at 1 year, while the 120-min glucose concentration was 90 mg/dl at baseline and 96 mg/dl at 1 year. The 0-min insulin concentrations were 2.9 mU/l at baseline and 5.3 mU/l at 1 year, while the 120-min insulin levels were 7.7 mU/l at baseline and 11 mU/l at 1 year. The proportions of HbA(1C) were 5.2 and 5.4% at baseline and 1 year, respectively. HOMA and QUICKI values were 0.59 and 0.42, respectively, at baseline, and 1.13 and 0.38 at 1 year. In KIGS, there were 1909 children born SGA aged 9.1 (3.9-13.3) years with a birth weight SDS of -2.6 (-4.0 to -1.5), birth length SDS of -2.7 (-4.3 to -1.3) and height SDS of -2.71 (-3.9 to -1.8) prior to treatment. GH doses ranged from 0.032 to 0.037 in the USA and from 0.022 to 0.023 mg/kg/day in the remaining countries in KIGS. Neither total (187 vs. 183) nor serious (14 vs. 10) adverse events occurred more commonly in the SGA group than in the ISS group. Although respiratory adverse events occurred more commonly in children born SGA (34.3 vs. 16.8; p < 0.05), endocrine (12.0 vs. 2.7; p < 0.05) and hepatobiliary (6.2 vs. 1.1; p < 0.05) adverse events occurred more commonly in children with ISS. CONCLUSIONS: As expected, a reduction in insulin sensitivity occurred during GH treatment of children born SGA; however, glucose tolerance remained normal. No adverse events were reported more commonly in children born SGA than in those with ISS. Minor differences in adverse events reporting within organ systems between children born SGA and those with ISS are probably due to variable under-reporting of adverse events. GH appears to be a safe drug to use at current doses as a growth-promoting agent in short children born SGA.
Asunto(s)
Estatura/efectos de los fármacos , Desarrollo Infantil/efectos de los fármacos , Hormona del Crecimiento/efectos adversos , Recién Nacido Pequeño para la Edad Gestacional/crecimiento & desarrollo , Adolescente , Niño , Preescolar , Femenino , Glucosa/metabolismo , Prueba de Tolerancia a la Glucosa , Hemoglobina Glucada/metabolismo , Humanos , Recién Nacido , Insulina/metabolismo , Resistencia a la Insulina , MasculinoRESUMEN
Valtropin (somatropin, BioPartners and LG Life Sciences [LGLS]) is a recombinant human growth hormone (GH) preparation produced using a yeast expression system. An open single-arm phase III study was conducted to evaluate efficacy and safety at a dose of 0.16 IU/kg/day (0.053 mg/kg/day) s.c. for 12 months in the treatment of short stature in girls (n = 30, aged 2-9 years) with Turner's syndrome. The primary efficacy variable was height velocity (HV) at 12 months. Secondary efficacy variables included serum GH dependent growth factors. HV increased from 3.8 +/- 1.8 cm/yr at baseline to 9.7 +/- 1.6 cm/yr (mean +/- SD) after 12 months of treatment. Marked treatment effects were also observed on other growth parameters, serum insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3). Treatment was well tolerated with no significant adverse events. It is concluded that Valtropin is as safe and effective as other human GH preparations for the treatment of growth failure in girls with Turner's syndrome.
Asunto(s)
Estatura/efectos de los fármacos , Trastornos del Crecimiento/tratamiento farmacológico , Hormona de Crecimiento Humana/uso terapéutico , Síndrome de Turner/tratamiento farmacológico , Niño , Preescolar , Femenino , Estudios de Seguimiento , Trastornos del Crecimiento/complicaciones , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Proteínas Recombinantes , Resultado del Tratamiento , Síndrome de Turner/complicacionesRESUMEN
Long-term GH replacement therapy is indicated for children with growth failure due to GH deficiency (GHD). We evaluated the feasibility of administering a long-acting GH preparation [Nutropin Depot (somatropin, rDNA origin) for injectable suspension] to prepubertal children with GHD by examining pharmacokinetic and pharmacodynamic response parameters after single or multiple doses. Data were collected from three studies involving 138 children treated with Nutropin Depot 0.75 mg/kg once per month, 0.75 mg/kg twice per month, or 1.5 mg/kg once per month. Twenty-two patients underwent intensive sampling to estimate mean peak serum GH concentrations (C(max)) and time to achieve C(max) for GH and IGF-I. Thereafter, weekly serum concentrations were measured and compared with baseline. C(max) and area under the curve were approximately proportional to the dose administered. Fractional area under the curve data indicate that at least 50% of GH exposure occurs during the first 2 d after administration. Serum GH levels remained above 1 microg/liter for 11-14 d. IGF-I levels remained above baseline for 16-20 d, but increases were not proportional to dose. After multiple doses over a 6-month period, peak and trough concentrations showed no progressive accumulation of GH, IGF-I, or IGF binding protein-3. Nutropin Depot administration once or twice per month provides serum levels of GH and IGF-I expected to promote growth, without accumulation of GH, IGF-I, or IGF binding protein-3, in children with GHD.
Asunto(s)
Hormona de Crecimiento Humana/administración & dosificación , Hormona de Crecimiento Humana/deficiencia , Hormona de Crecimiento Humana/farmacocinética , Niño , Preescolar , Preparaciones de Acción Retardada , Esquema de Medicación , Femenino , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Errores Innatos del Metabolismo/sangre , Errores Innatos del Metabolismo/tratamiento farmacológicoRESUMEN
Avicennia marina is an important mangrove species with a wide geographical and climatic distribution which suggests that large amounts of genetic diversity are available for conservation and breeding programs. In this study we compare the informativeness of AFLPs and SSRs for assessing genetic diversity within and among individuals, populations and subspecies of A. marina in Australia. Our comparison utilized three SSR loci and three AFLP primer sets that were known to be polymorphic, and could be run in a single analysis on a capillary electrophoresis system, using different- colored fluorescent dyes. A total of 120 individuals representing six populations and three subspecies were sampled. At the locus level, SSRs were considerably more variable than AFLPs, with a total of 52 alleles and an average heterozygosity of 0.78. Average heterozygosity for AFLPs was 0.193, but all of the 918 bands scored were polymorphic. Thus, AFLPs were considerably more efficient at revealing polymorphic loci than SSRs despite lower average heterozygosities. SSRs detected more genetic differentiation between populations (19 vs 9%) and subspecies (35 vs 11%) than AFLPs. Principal co-ordinate analysis revealed congruent patterns of genetic relationships at the individual, population and subspecific levels for both data sets. Mantel testing confirmed congruence between AFLP and SSR genetic distances among, but not within, population comparisons, indicating that the markers were segregating independently but that evolutionary groups (populations and subspecies) were similar. Three genetic criteria of importance for defining priorities for ex situ collections or in situ conservation programs (number of alleles, number of locally common alleles and number of private alleles) were correlated between the AFLP and SSR data sets. The congruence between AFLP and SSR data sets suggest that either method, or a combination, is applicable to expanded genetic studies of mangroves. The codominant nature of SSRs makes them ideal for further population-based investigations, such as mating-system analyses, for which the dominant AFLP markers are less well suited. AFLPs may be particularly useful for monitoring propagation programs and identifying duplicates within collections, since a single PCR assay can reveal many loci at once.
RESUMEN
Adrenarche is the puberty of the adrenal gland. The descriptive term "pubarche" indicates the appearance of pubic hair, which may be accompanied by axillary hair. This process is considered premature if it occurs before age 8 yr in girls and 9 yr in boys. The chief hormonal products of adrenarche are DHEA and DHEAS. The well-documented evolution of adrenarche in primates and men is incompatible with either a neutral or harmful role for DHEA and implies most likely a positive role for some aspects of young adult pubertal maturation and developmental maturation. Premature adrenarche has no adverse effects on the onset and progression of gonadarche and/or final height. Mechanisms for initiation of adrenal androgen secretion at adrenarche are still not well understood. Maturational increases in 17-hydroxylase and 17,20-lyase are seen together with a lower activity of 3beta-hydroxysteroid dehydrogenase (3beta-HSD). There is good evidence that the zona reticularis is the source of adrenal androgens. Adrenarche and gonadarche are regulated differently. Although premature adrenarche has been thought to be a benign, normal variant of puberty, our findings indicate that, for certain girls, premature adrenarche represents an early clinical feature of syndrome X (obesity, hypertension, dyslipidemia, insulin resistance). Perhaps the early identification of these patients will permit early therapy, such as lifestyle changes, including dietary and activity level intervention. As insulin resistance is an underlying feature of premature adrenarche, it seems rational to assess the efficacy and safety of using insulin-sensitizing agents to treat these individuals. In the absence of controlled longitudinal studies, the cross-sectional data available from our studies suggest that premature pubarche driven by premature adrenarche and hyperinsulinemia may precede the development of ovarian hyperandrogenism, and this sequence may have an early origin with low birth weight serving as a marker. Premature adrenarche may thus be a forerunner of syndrome X in some girls.
Asunto(s)
Glándulas Suprarrenales/crecimiento & desarrollo , Glándulas Suprarrenales/metabolismo , Andrógenos/metabolismo , Glucemia/análisis , Niño , Deshidroepiandrosterona/fisiología , Femenino , Humanos , Hiperandrogenismo , Insulina/sangre , Insulina/fisiología , Resistencia a la Insulina , Factor I del Crecimiento Similar a la Insulina/fisiología , Masculino , Angina Microvascular/diagnóstico , Pubertad , Esteroide 17-alfa-Hidroxilasa/fisiologíaRESUMEN
The purpose of this study was to determine whether the fasting glucose/insulin ratio is a useful screening test for insulin resistance in prepubertal girls with premature adrenarche. The glucose/insulin ratio was compared with the insulin sensitivity index calculated from the frequently sampled iv glucose tolerance test with tolbutamide using the minimal model computer program. Thirty-three prepubertal girls (22 Caribbean Hispanic and 11 African American; mean age, 6.8 yr; bone age, 8 yr) were studied. All underwent a 60-min ACTH stimulation test. The fasting glucose/insulin ratio was also compared with IGF-binding protein-1 and ACTH-stimulated androgen levels. Insulin sensitivity correlated significantly with the glucose/insulin ratio (0.76; P < 0.001), fasting insulin (0.75; P < 0.001), and IGF-binding protein-1 (0.59; P < 0.005). Stepwise regression analysis with the insulin sensitivity index as the dependent variable showed that the fasting glucose/insulin ratio was significantly predictive of the insulin sensitivity index (P < 0.002). When viewed as a screening test, setting a value of the fasting glucose/insulin ratio of less than 7 as abnormal and of less than 5.7 x 10(-4) min/microU.ml for the insulin sensitivity index as evidence of insulin resistance (normal prepubertal insulin sensitivity index, >5.7 x 10(-4) min/microU.ml), the sensitivity of the fasting glucose/insulin ratio was 87%, and the specificity was 89%. Furthermore, those girls with a low glucose/insulin ratio (<7) had higher body mass index, fasting insulin, free T, and ACTH-stimulated 17-hydroxypregnenolone and lower fasting IGF-binding protein-1 and SHBG than those girls with a glucose/insulin ratio greater than 7. The fasting glucose/insulin ratio is a useful screening test for insulin resistance in prepubertal Caribbean Hispanic and African American girls with premature adrenarche.
Asunto(s)
Enfermedades de la Corteza Suprarrenal/sangre , Andrógenos/metabolismo , Glucemia/análisis , Resistencia a la Insulina , Insulina/sangre , Pubertad , Niño , Preescolar , Ayuno , Femenino , HumanosRESUMEN
Treatment of naive children with GH deficiency has relied upon long-term replacement therapy with daily injections of GH. The daily schedule may be inconvenient for patients and their caregivers, possibly promoting nonadherence with the treatment regimen or premature termination of treatment. We studied a new sustained release GH formulation, administered once or twice monthly, to determine its efficacy and safety in this population. Seventy-four prepubertal patients with documented GH deficiency were randomized to receive sustained release recombinant human GH at either 1.5 mg/kg once monthly or 0.75 mg/kg twice monthly by sc injection in a 6-month open-label study. Efficacy was determined by growth data from 69 patients completing 6 months and 56 patients completing 12 months in an extension study. Growth rates were significantly increased over baseline and were similar for the two dosage groups. The mean (+/-SD) annualized growth rate (pooled data) was 8.4 +/- 2.1 cm/yr at 6 months, and the growth rate was 7.8 +/- 1.8 at 12 months compared with 4.5 +/- 2.3 at baseline. Standardized height, bone age, and predicted adult height assessments demonstrated catch-up growth without excessive skeletal maturation. Injection site-related events (including pain, erythema, and nodules) were the most commonly reported adverse events; no serious adverse events related to treatment were reported. Laboratory studies documented no accumulation of trough GH or IGF-I levels during treatment, nor did glucose intolerance or persistent hyperinsulinism develop. Sustained release recombinant human GH is safe and effective for long-term GH replacement in children with GH deficiency. Patients achieved similar growth velocities when sustained release GH was given once or twice monthly. The enhanced convenience of this dosage form may result in greater long-term adherence to the treatment regimen.
Asunto(s)
Hormona del Crecimiento/administración & dosificación , Hormona de Crecimiento Humana/deficiencia , Anticuerpos/sangre , Niño , Preescolar , Femenino , Crecimiento/efectos de los fármacos , Hormona del Crecimiento/efectos adversos , Hormona del Crecimiento/inmunología , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , MasculinoRESUMEN
Many children with chronic renal insufficiency (CRI) show growth retardation and severely delayed pubertal development. Successful renal transplantation (RTx) also rarely results in full growth rehabilitation. Pubertal height gain in CRI patients is only 58% and 48% of that observed in late-maturing boys and girls, respectively. Growth retardation in both CRI and RTx patients is not the result of abnormal GH secretion or decreased levels of IGF-I, but rather of elevated levels of IGFBPs inhibiting the bioavailability of the IGFs. In RTx patients prednisone may also inhibit growth directly via inhibition of bone matrix formation. Several studies have convincingly shown that GH therapy at a dose of 4 IU/m2/day results in a sustained improvement of growth in prepubertal and pubertal children with CRI and in growth-retarded prepubertal and pubertal post-transplant patients. The following consensus was reached concerning optimal therapy of puberty in children with chronic renal disease. GH therapy does not lead to an earlier start of puberty. It is safe to give GH to RTx patients if transplant function is stable. GH therapy will not accelerate bone maturation and can improve the final height of children with CRI and after RTx. Increasing the GH dose above 4 IU/m2/day in pubertal RTx patients does not increase height gain or final height and is not advised as it may increase insulin resistance. GH should best be started before the start of the pubertal growth spurt but will still be effective in RTx patients with advanced bone age. GH testing should not be a prerequisite for starting GH therapy. It is important to optimise other therapies during puberty. During GH therapy of RTx patients use minimum daily, not alternate-day, steroid dosing. Further research is still required on the possible long-term effects of GH therapy in children with chronic diseases. Two studies demonstrated improved long-term growth and final height within the target height range, without significant side effects. Renal graft function did not deteriorate more than in matched controls. A GH dose of 4 IU/m2/day proved adequate.
Asunto(s)
Fallo Renal Crónico/terapia , Pubertad/fisiología , Adolescente , Niño , Trastornos del Crecimiento/tratamiento farmacológico , Trastornos del Crecimiento/etiología , Hormona del Crecimiento/uso terapéutico , Hormonas/sangre , Hormonas/fisiología , Humanos , Fallo Renal Crónico/sangre , Fallo Renal Crónico/complicacionesRESUMEN
GnRHa have been used in the treatment of central precocious puberty (CPP) for a decade and some final results of this therapy are now available. Treatment preserves height potential in younger patients and a complete recovery of the hypothalamic-pituitary-gonadal axis occurs at the end of treatment. However, some aspects of the management of CPP are still debated. Probably the age limits between normal and precocious puberty have to be lowered, and new diagnostic tools will modify and simplify diagnostic criteria. The possibility of progression of premature thelarche into precocious puberty, the pathogenesis of organic and idiopathic precocious puberty, the criteria for decision to treat and to stop treatment and the utility of an association with GH treatment will be better understood in the future. Follow-up of patients after stopping therapy includes frequency and characteristics of menses, the possible higher incidence of polycystic ovary-like syndrome and the correct achievement of a normal peak bone mass and body composition. In this review we discuss some of these points, with particular attention to precocious puberty in girls.
Asunto(s)
Pubertad Precoz/terapia , Adolescente , Estatura/efectos de los fármacos , Niño , Femenino , Hormona del Crecimiento/efectos adversos , Hormona del Crecimiento/uso terapéutico , Humanos , Masculino , Pubertad Precoz/diagnóstico , Pubertad Precoz/etiologíaRESUMEN
Saizen (recombinant growth hormone [GH]), 0.2 mg/(kg x wk), was given in an open-label fashion for an average of 51 mo to 27 children with presumed idiopathic GH deficiency who had withdrawn from a trial of Geref (recombinant GH-releasing hormone [GHRH] 1-29) because of inadequate height velocity (HV) (25 children), the onset of puberty (1 child), or injection site reactions (1 child). Measurements were made every 3-12 mo of a number of auxologic variables, including HV, height standard deviation score, and bone age. The children in the study showed excellent responses to Saizen. Moreover, first-year growth during Saizen therapy was inversely correlated with the GH response to provocative GHRH testing carried out 6 and 12 mo after the initiation of Geref treatment. These findings indicate that GH is effective in accelerating growth in GH-deficient children who do not show or maintain a satisfactory response to treatment with GHRH. In addition, they suggest that the initial response to GH therapy used in this way can be predicted by means of provoc-ative testing.
Asunto(s)
Hormona Liberadora de Hormona del Crecimiento/uso terapéutico , Hormona de Crecimiento Humana/deficiencia , Hormona de Crecimiento Humana/uso terapéutico , Adolescente , Determinación de la Edad por el Esqueleto , Estatura , Niño , Preescolar , Femenino , Humanos , Factor I del Crecimiento Similar a la Insulina/análisis , Masculino , Proteínas Recombinantes/uso terapéutico , Resultado del TratamientoRESUMEN
Before chromosomal analysis became available, the diagnosis of Turner's syndrome was based on the characteristics independently described by Otto Ullrich and Henry Turner, such as short stature, gonadal dysgenesis, typical, visible dysmorphic stigmata, and abnormalities in organs, which present in individuals with a female phenotype. Today, Turner's syndrome or Ullrich-Turner's syndrome may be defined as the combination of characteristic physical features and complete or part absence of one of the X chromosomes, frequently accompanied by cell-line mosaicism. The increasing interest in Turner's syndrome over the past two decades has been motivated both by the quest for a model by which the multi-faceted features of this disorder can be understood, and the endeavour to provide life-long support to the patient. New developments in research allow patients with Turner's syndrome to have multidisciplinary care.