Turner syndrome is one of the more common genetic disorders, associated with abnormalities of the X chromosome, and occurring in about 50 per 100,000 liveborn girls. Turner syndrome is usually associated with reduced adult height, gonadal dysgenesis, and thus insufficient circulating levels of female sex steroids, and infertility. A number of other signs and symptoms are seen more frequent with the syndrome. Morbidity and mortality is increased. The average intellectual performance is within the normal range. With respect to epidemiology, […]

In addition to stimulating body growth, growth or somatotrophic hormone plays an important role in metabolism, body composition, lipid profile, cardiovascular status and longevity. Its control is multiregulated by hormones, metabolites and hypothalamic peptides. Obtained data of the isolated growth hormone deficiency (IGHD) after the description of the IVS1+1G®A GHRH receptor gene mutation in individuals of Itabaianinha County are reviewed. New perspectives about the growth hormone resistance model, the importance of GHRH in the control of GH secretion, the frequency […]

The extension of the life expectancy led to strategies aimed at improving the quality of life and productivity of aging persons. It is well known that, after the pubertal peak, the activity of the GH/IGF-1 axis progressively declines. Consequently, many normal individuals older than 60 years have 24-hour GH secretion indistinguishable from that of an adult patient with GH deficiency due to hypothalamic-pituitary lesions (ADGH). This physiological phenomenon is paralleled with many clinical aspects of ADGH, such as increased visceral […]

The metabolic syndrome (MS) is characterized by alterations in carbohydrate metabolism, obesity, hypertension and dislipidemia. These metabolic alterations interfere with some endocrine axes controlled by the hypothalamus and the pituitary. Central obesity might be associated to a state of subclinical hypercortisolism and hypertension, secondary to an activation of the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system. MS is also a state of relative hyposomatotropism, probably related to visceral fat. Furthermore, high levels of free fat acids and hyperinsulinemia, secondary to […]

We have evaluated 70 patients with GH deficiency, 39 females and 31 males, ranging in age from 18 to 69 years (mean: 38.3±13.5), from 3 centers in Brazil. GH replacement dose was different among the centers, as well as IGF-1 response to GH, which was more pronounced in patients using the highest GH dose. GH replacement led to a significant increase of IGF-1 and HDL cholesterol, as well as bone mineral density (BMD) and to a significant decrease in total […]

Bone remodeling is a physiologic process regulated by the interaction between the bone cells and a variety of hormones, cytokines, growth factors and inflammatory mediators. The central nervous system (CNS) has been proposed as a new regulatory element, acting through the release of neuronal messengers, which create a link between CNS and skeleton. There have been experimental and clinical evidence of neuroendocrine control of bone mass, with several factors implicated in this mechanism, including neuropeptides, neurotransmitters, leptin and others. Clinically, […]

Pycnodysostosis (PYCD) is a rare autosomal recessive skeletal dysplasia, due to a defect in the gene encoding cathepsin K, and characterized by short stature (SS), osteosclerosis, acro-osteolysis, skull deformities, and bone fragility. Although SS is characteristic in PYCD, GH deficiency has been reported only in some cases. We present two isolated cases, with typical clinical-radiological pictures. Case 1: a 9 year-old boy, offspring of consanguineous parents, presenting SS, osteosclerosis, bone fragility, bilateral ocular proptosis, frontal bossing, brachycephaly, wide cranial sutures, […]

At present, the impairment of linear growth remains one of the major obstacles to successful social adaptation of children and adolescents with chronic renal insufficiency (CRI), being the recombinant human growth hormone (rhGH) a therapeutic option. We evaluated growth and body composition (BC) in 11 prepubertal patients (9M/2F; 3.5-12.8y) with CRI and short stature and/or slow growth velocity treated with rhGh (0.7-1.0IU/Kg/week) for 18 months. Anthropometry and BC, examined by a tetrapolar bioeletrical impedance, were evaluated before, 6, 12 and […]

The integrity of the GHRH-GH-IGF-I axis is important for normal growth. Mutations in genes involved in any of the steps result in short stature. Disorders of this axis can be divided in: 1) GH deficiency combined with deficiencies of other pituitary hormones due to alterations in transcription factors involved in pituitary organogenesis (HESX1/RPX, LHX3 e LHX4, PROP-1, PIT-1); 2. Isolated GH deficiency (GHRH receptor, GH-1, bioinactive GH); and 3. GH insensitivity (GH receptor, IGF-I gene and IGF-I receptor). Genes involved […]

The diagnosis of IGF-1 deficiency due to GH-IGF abnormalities must use the most appropriate parameters for age and pubertal stage. We propose the diagnosis of growth hormone deficiency (GHD) based in an hierarchy of clinical and laboratory data. Clinical evaluation and general laboratory tests, e.g. thyroid tests, permit to exclude other causes of IGF deficiency that are not intrinsic to the GH-IGF axis. In these, the measurement of serum IGF-1 must be the first step in prepubertal, pubertal and elderly […]

Acromegaly is a characteristic clinical syndrome caused in most cases by a GH-producing pituitary macroadenoma. Tumoral GH hypersecretion results in skeletal changes, metabolic abnormalities, multi-systemic complications and a significant increase in the overall mortality. The diagnosis is suspected on clinical grounds, and it is normally confirmed by biochemical and radiological examinations. From the biochemical standpoint, the diagnostic approach for demonstration of GH excess involves either basal hormone measurements, mainly GH and insulin-like growth factor-1 (IGF-1), and endocrine tests, such as […]