Osteometabolic profile and bone mass in the transition phase: ethnic differences in Brazilians treated with somatropin during childhood

Abstract Objective: The main growth hormone action is to promote linear growth increasing protein synthesis stimulation and osteoblastic activity. Peak bone mass extends from adolescence to 30 years of age. Several factors may influence this acquisition and prevent fracture risk in adulthood, such as genetic potential, GH, ethnicity, and lifestyle factors. This study aims to compare bone mass and osteometabolic profile of white and Afro-descendant Brazilian adolescents in the transition phase, who were treated with human recombinant growth hormone in childhood. Methods: The authors selected 38 adolescents from the Transition Outpatient Clinic of the University of São Paulo. Lumbar spine and total body bone mineral density (BMD) and bone mineral content (BMC), serum calcium, 25-OH-vitamin D and bone markers were analyzed at the rhGH withdrawal. Results: The mean age was 16.8 ± 1.6 years. There were 21 Afro-descendant and 17 whites. Thirty-four percent of the sample presented vitamin D insufficiency, 66% inadequate calcium intake and 44.7% physical inactivity. The Afro-descendants showed a lower lumbar spine and total body Z scores than those of the whites (p = 0.04 and p = 0.03, respectively), as well as their mean body weight (p = 0.03). There were no differences in the remaining osteometabolic parameters. Conclusion: As most adolescents had vitamin D insufficiency, low calcium intake, and physical inactivity, calcium, and cholecalciferol supplementation and lifestyle changes should be encouraged. The Brazilian Afro-descendant may be a vulnerable group for low bone mass, requiring

Management of hypopituitarism: a perspective from the Brazilian Society of Endocrinology and Metabolism

ABSTRACT Hypopituitarism is a disorder characterized by insufficient secretion of one or more pituitary hormones. New etiologies of hypopituitarism have been recently described, including head trauma, cerebral hemorrhage, and drug-induced hypophysitis. The investigation of patients with these new disorders, in addition to advances in diagnosis and treatment of hypopituitarism, has increased the prevalence of this condition. Pituitary hormone deficiencies can induce significant clinical changes with consequent increased morbidity and mortality rates, while hormone replacement based on current guidelines protects these patients. In this review, we will first discuss the different etiologies of hypopituitarism and then address one by one the clinical aspects, diagnostic evaluation, and therapeutic options for deficiencies of TSH, ACTH, gonadotropin, and GH. Finally, we will detail the hormonal interactions that occur during replacement of pituitary hormones.

Insulin signaling in the whole spectrum of GH deficiency

ABSTRACT GH is one of the insulin counterregulatory hormones which acts in the opposite way to insulin, increasing the glucose production by the liver and kidneys and decreasing glucose uptake from peripheral tissues, thus being a hyperglycemic hormone. When in excess, as in acromegaly, it induces glucose intolerance and diabetes. As expected, patients with GH deficiency (GHD) have hypoglycemia, especially in early childhood, but as GH is also a lipolytic hormone, these patients are becoming obese with higher percentages of body fat. Although obesity in general is directly related to insulin resistance, in patients with GH secretion disorders this relationship may be altered. In acromegaly there is a decrease in fat mass with worsening insulin sensitivity and mice with isolated GHD are characterized by greater insulin sensitivity despite excess fat mass. In humans with GHD, body composition shows increased body fat and decreased free fat mass, but the results regarding insulin sensitivity are still controversial in these patients. These discrepant results regarding insulin sensitivity in patients with GHD suggest the existence of other variables influencing these results. In the present review, we will try to follow the path of the different researches conducted on this subject, both in animal and human models, with the goal of understanding the current knowledge of insulin sensitivity across the spectrum of GHD. Arch Endocrinol Metab. 2019;63(6):582-91

Male-female differences in 6-sulfatoxymelatonin excretion in hypopituitary patients

ABSTRACT Objective To evaluate melatonin secretion in adult hypopituitary patients with Growth Hormone deficiency (AGHD) on and off replacement therapy. Subjects and methods We studied 48 subjects: 12 (6 males) untreated AGHD (AGHDnt), 20 (10 males) treated AGHD (AGHDt) and 16 healthy subjects (8 males) as control group (CG). We measured urinary 6-sulfatoxymelatonin (6-SM) in total (24 h samples), nocturnal (6-SMn): 1800-0800 and diurnal samples (6-SMd): 0800-1800. Results Significant differences were observed among the 3 groups of male subjects, in total 6-SM (p < 0.05), nocturnal 6-SM (p < 0.02) and nighttime-daytime delta values (p < 0.003). CG had significantly higher values than the AGHDnt in total 6-SM (p < 0.01), nocturnal 6-SM (p < 0.05) and nighttime-daytime delta values (p < 0.01). AGHDt patients showed significantly higher levels in nighttime-daytime delta values than AGHDnt patients (p < 0.05). In females, no significant differences were found among the 3 groups studied in total, nocturnal, diurnal or nighttime-daytime delta values. In males, significant correlations were found among total 6-SM (r = 0.58; p = 0.029), nocturnal 6-SM (r = 0.70; p = 0.006) and nighttime-daytime delta values (r = 0.71; p = 0.004) vs. serum IGF-1 levels in subjects evaluated. In females, significant correlations were found among total 6-SM (r = 0.57; p = 0.02) vs. serum IGF-1 levels in subjects evaluated. A tendency towards a significant correlation was found in diurnal 6-SM (r = 0.48; p = 0.07). Conclusions Our findings show a sexual dimorphism in 6-SM excretion in AGHD patients and provide an interesting approach to a further understanding of some chronobiological disorders involved in GH deficiency.

Clonidine-stimulated growth hormone concentrations (cut-off values) measured by immunochemiluminescent assay (ICMA) in children and adolescents with short stature

OBJECTIVES: To establish cut-off values for growth hormone concentrations using clonidine as a secretagogue and an immunochemiluminescent assay as the method of measurement and to analyze the response time as well as the influence of gender, nutritional status and pubertal stage. METHODS: A total of 225 tests were performed in 3 patient groups, categorized as group 1 (normal), group 2 (idiopathic short stature) and group 3 (growth hormone deficiency). Among the 199 disease-free individuals, 138 were prepubertal, and 61 were pubertal. Clonidine (0.1 mg/m2) was orally administered, and the growth hormone level was measured by immunochemiluminescent assay. The growth hormone peak and the difference between the growth hormone peak and the baseline level were then analyzed. Statistical analyses were performed using Student’s t-test or the Mann-Whitney test and Kruskal-Wallis test followed by Dunn’s post hoc test. Cut-off values were determined using a receiver operating characteristic curve. RESULTS: Group 1 and group 2 had no difference in growth hormone peak, gender, body mass index standard deviation score, or pubertal stage. Group 3 exhibited a significantly lower growth hormone peak than the other groups did. The receiver operating characteristic curve demonstrated that growth hormone concentrations ≥ 3.0 ng/mL defined responsiveness to clonidine. In total, 3.02% of individuals in group 1 and group 2 were considered false positive, i.e., these children lacked growth hormone deficiency and had a peak below 3.0 ng/mL. CONCLUSION: Clonidine-stimulated growth hormone concentrations ≥3 ng/mL, as measured by immunochemiluminescent assay, suggest responsiveness to the stimulus regardless of gender, body mass index standard deviation score or pubertal stage.

Investigação de baixa estatura: aspectos clínicos, laboratoriais e moleculares da insensibilidade ao hormônio de crescimento / Short stature investigation: clinical, laboratorial and genetic aspects concerning the trowth hormone insensitivity (GHI)

Neste artigo são descritos os aspectos clínicos, laboratoriais e genéticos da investigação da baixa estatura, dando ênfase para o diagnóstico da insensibilidade ao hormônio de crescimento (IGH). O paciente apresentado possuía características clínicas típicas de pacientes com IGH e em idade pré-púbere seus achados laboratoriais eram compatíveis com este diagnóstico (IGF-1 e IGFBP3 baixos, GH basal e pós-estímulo elevados). No entanto, quando avaliado durante a puberdade, as dosagens de IGF-1 e IGFBP-3 foram normais, dificultando o diagnóstico. O estudo molecular identificou mutação no exon 7 do gene do receptor do hormônio de crescimento (S226I). Discutiram-se os passos realizados para identificar a mutação e demonstrar que ela é responsável pelo fenótipo observado no paciente. Também será feita revisão dos casos de IGH descritos no Brasil e dos novos defeitos moleculares descritos nesta doença.

It is reported in this study the clinical, laboratory and genetic aspects of short stature investigation with emphasis to the diagnostic approach of growth hormone insensitivity (GHI). This patient in case presented typical clinical features of GHI and his laboratory findings at prepubertal age were typical of those observed in GHI patients (low IGF-1 and IGFBP-3 levels, with high basal and stimulated GH levels). However, during the puberty, he presented normal IGFBP-3 and IGF-1 levels that hindered the diagnosis. The molecular study disclosed a mutation in exon 7 of growth hormone receptor gene (S226I). The steps that demonstrated the causative effect of this mutation are shown here, and also a review of Brazilian GHI cases is given and new molecular defects in this field are discussed as well.

Aspectos diagnósticos e terapêuticos da síndrome de Sheehan: [revisão] / Clinical, laboratorial and therapeutics aspects of Sheehan's syndrome: [review]

A síndrome de Sheehan se caracteriza pelo hipopituitarismo pós-parto secundário à necrose hipofisária decorrente de hipotensão ou choque em virtude de hemorragia maciça durante ou logo após o parto. Sua freqüência vem caindo em todo o mundo, principalmente em países e regiões mais desenvolvidas em razão da melhora nos cuidados obstétricos, contudo, ainda é freqüente em países em desenvolvimento onde os cuidados obstétricos são mais precários. A síndrome de Sheehan pode evoluir de maneira lenta com diagnóstico muitas vezes tardio e, ainda que alguns sinais de insuficiência hipofisária ocorram, logo após o parto, são pouco valorizados. Seu diagnóstico precoce e o tratamento adequado são importantes para redução da morbimortalidade das pacientes. Esta revisão tem por objetivo descrever aspectos clínicos, laboratoriais e terapêuticos da síndrome de Sheehan, incluindo a nossa experiência pessoal na reposição com GH recombinante neste grupo de pacientes.

Sheehan's syndrome is characterized by hypopituitarism that occurs as a result of ischemic pituitary necrosis due to severe postpartum hemorrhage. Nowadays it is not usually seen in developed countries because of the improvements in obstetric care. However, in developing countries it is still frequent and probably one of the most common causes of hypopituitarism. Most patients usually present it months to years later, with a history of failure of postpartum lactation, failure to resume menses and other signs of panhypopituitarism. In mild forms of the disease, patients may remain undetected and do not receive treatment for many years. Early diagnosis and appropriate treatment are important to reduce the morbimortality of the patients with Sheehan's syndrome. The aim of this review is to describe clinical, laboratorial and therapeutic aspects of Sheehan's syndrome, including our experience in the replacement of recombinant GH in these patients.

Eficácia, segurança e aderência ao tratamento de longo prazo com hormônio de crescimento (GH) em adultos com deficiência de GH / Efficacy, safety and compliance of long-term growth hormone (GH) replacement therapy in adults with GH deficiency

OBJETIVO: Avaliar a eficácia, a segurança e a aderência de quatro anos de tratamento com GH em 18 adultos [12 mulheres, 6 homens, com idade média de 50,5 anos (25-66 anos)] com deficiência grave de GH (DGH). MÉTODOS: Avaliações clínica, laboratorial e de composição corporal (DXA) realizadas antes e anualmente após o início do GH, e ecocardiografia realizada antes e após quatro anos de tratamento. Dose de 0,2 mg GH/dia mantida fixa no primeiro ano, com posteriores ajustes para normalizar IGF-1. RESULTADOS: Redução significativa da gordura corporal total (média 2,8 kg) e da gordura truncal (média 1,9 kg), associadas com aumento da massa magra (média 0,8 kg) e aumento da densidade mineral óssea (DMO) em coluna lombar e fêmur, particularmente nos sítios com T-escore menor que 1,0 na avaliação basal. Houve piora dos níveis de insulina e HOMA no primeiro ano de terapia, mas ao final do quarto ano os valores de glicose, insulina, HOMA e hemoglobina glicosilada não eram diferentes dos basais. Desenvolveram diabetes tipo 2 no seguimento dois pacientes com intolerância à glicose pré-tratamento. O colesterol total e o LDL colesterol reduziram significativamente, e as mudanças foram proporcionais aos valores basais. Os parâmetros ecocardiográficos não se alteraram. Os efeitos colaterais foram leves e bem tolerados. Não foi observada recorrência tumoral. Baixa adesão ao tratamento (estimada por níveis baixos de IGF-1) ocorreu em quatro (22 por cento), dois (11 por cento) e seis (30 por cento) pacientes ao final do segundo, terceiro e quarto ano, respectivamente. CONCLUSÕES: Quatro anos de tratamento com GH em adultos com DGH teve impacto positivo sobre a composição corporal, a DMO e o perfil lipídico, e nenhum efeito sobre sensibilidade insulínica e o coração. A intolerância à glicose deve ser cuidadosamente monitorada no tratamento de longo prazo.

AIM: To study efficacy, safety and compliance of GH therapy for 4 years in 18 GH deficient (GHD) adults [12 women; mean age 50.5 yrs (25-66 yrs)]. METHODS: Clinical, biochemical and body composition (DXA) measurements were performed before and every year after GH therapy. Ecocardiography was performed at baseline and after 4 years. Dose of GH was 0.2 mg/day during the first year with subsequent titration to attain normal IGF-1 levels. RESULTS: There was a significant reduction of total body fat (mean 2.8 kg), truncal fat (mean 1.9 kg) and an increase of lean body mass (mean 0.8 kg) and bone mineral density (BMD) on lumbar spine and femur, particularly in sites with T-score < -1,0 at baseline. Insulin levels and HOMA index worsened in the first year, but at the end no changes were noted on glucose, insulin, HOMA index and glycosylated hemoglobin. Two patients with altered glucose tolerance at baseline developed type 2 diabetes during follow-up. Total and LDL-cholesterol were significantly lower after therapy, with changes directly associated with baseline values. Cardiac parameters did not change. Side effects were mild and disappeared spontaneously. Tumor recurrence was not observed. Low compliance (estimated by low IGF-1 levels) was observed in 4 (22 percent), 2 (11 percent) and 6 (33 percent) patients at the end of second, third and fourth year, respectively. CONCLUSIONS: Four years of GH therapy in GHD adults had a positive impact on body composition, BMD and lipid profile, with no effects on insulin sensitivity and heart. Glucose tolerance should be monitored carefully during long-term GH therapy.

Changes of Bone Turnover Markers after Treatment with Growth Hormone Therapy in Children with Growth Retardation / 대한내분비학회지

The effects of growth hormone(GH) deficiency and recombinant human GH replacement(0.5IU/kg per week) on bone mineral metabolism in 21GH-deficiency children were studied. All children had significantly reduction of bone density(Z score;-1.4+-0.71). After 1 month of therapy, the levels of serum insulin-like growth factor 1(IGF-1), osteocalcin(OC) and carboxyterminal propeptede of type 1 procollagen(PICP) were significantly elevated. But IGFBP-3 were not shown to change significantly. The changes in serum levels of PICP during the first month of recombinant human GH treatment were positively related to growth velocity, whereas the changes in IGF-1 and OC during the first month of therapy were not. We conclude that the recombinant human GH treatment caused significant modifications of mineral metablism and that the measurement of the changes of biochemical markers of bone metablism espacially PICP may be a useful tool in prediction improved growth velocity during long term GH replacement therpy.