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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pituitary, adrenal, and pancreatic functions were investigated in 9 patients with thalassaemia major. 9 a.m. plasma ACTH values were 148-480 pg/ml (normal range 15-70 pg/ml). Cortisol and growth hormone response to insulin-induced hypoglycaemia was normal in all. 24-hour urinary excretions of 17-ketosteroids and 17-hydroxycorticosteroids were normal. There was normal cortisol response to intramuscular injection of ACTH. In a physiological adrenal stimulation test there was a significantly smaller response to each physiological dose of tetracosactrin. 4 patients had diabetic glucose tolerance tests--none are clinically diabetic. The mean plasma glucose utilization constant (Kgl=2-02) is significantly smaller than normal. Plasma insulin response both in the oral and the intravenous glucose tolerance test was significantly smaller than normal. The data were consistent with severe and widespread impairment of endocrine function and a plausible explanation would be iron deposition in endocrine organs. It is suggested that pituitary hyperfunction of ACTH secretion is due to target organ unresponsiveness which can be shown in its early stages only by a physiological test of the adrenal cortex. Skin pigmentation in thalassaemia seems to be due to the melanophore-stimulating effect of this raised plasma ACTH.
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PMID:Endocrinopathy in thalassaemia major. 18 88

Endocrine function evaluations in 16 patients with beta-thalassemia indicate that hypogonadotropic hypogonadism, hypoparathyroidism, and reduced adrenocorticotropic hormone reserve occur frequently, whereas reduced growth hormone and thyroid reserve are less common manifestations. Hemosiderosis-induced damage of the endocrine glands seems to be the main cause for endocrine dysfunction in the patients studied.
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PMID:Endocrine abnormalities in thalassemia major. 43 75

Many clinical syndromes are associated with short stature, which can be proportionate or disproportionate. In the first group of syndromes, such as Turner syndrome and its variants, Down syndrome, Prader-Willi-Labhart syndrome, Noonan syndrome, and Silver-Russell syndrome growth hormone therapy can lead to increased growth velocity, but so far only short-term results have been reported. Growth hormone is contraindicated in syndromes with an increased risk of chromosomal breakage, e.g. Bloom syndrome. In disproportionate syndromes, such as hypochondroplasia, pseudopseudohypoparathyroidism, spina bifida, and hypophosphataemic rickets, the results of growth hormone therapy are not encouraging. Growth hormone therapy in children with rheumatoid arthritis and thalassaemia appears little effective. Long-term clinical trials of reasonable size are needed before reliable conclusions can be drawn about the value of growth hormone therapy in these conditions.
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PMID:[Growth hormone therapy in dysmorphic syndromes and chronic disease]. 144 9

Plasma levels of human growth hormone (hGH) were measured for an entire day every two hours, starting from midnight, in 6 healthy male subjects and in 6 male patients with homozygous beta-thalassemia, without evidence of any endocrine disease. The data were analyzed by the "cosinor" method, and the results show the presence of a significant (p < 0.05) circadian rhythm for hGH in both groups. Whereas no differences were found in mesors and acrophases between the two studied groups (p > 0.05), a statistically-significant (p < 0.05) difference was observed regarding amplitudes, being higher in the controls. These data suggest that in patients with beta-thalassemia major without evidence of any endocrine abnormality, the circadian secretory pattern of hGH is preserved, even if the rhythm amplitude is reduced: this could be a compensatory mechanism in order to stimulate growth.
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PMID:Persistence of human growth hormone circadian rhythm in patients with homozygous beta-thalassemia. 149 71

Regular bone survey radiographs have allowed identification of limb deformity and metaphyseal changes in several patients with thalassaemia major treated at the Adelaide Children's Hospital. Following the progression of limb deformity in five of these patients who were receiving human growth hormone therapy, the records of 25 thalassaemia patients were reviewed. Six patients had evidence of limb deformity, four of whom also had metaphyseal changes. Three additional patients had metaphyseal changes alone. Patients with either type of skeletal change shared similar characteristics, including younger age, earlier commencement of desferrioxamine therapy, better compliance and, in general, lower levels of ferritin. Females predominated in both groups. The frequency of sensorineural hearing loss was similar in affected and nonaffected groups and biochemical parameters, especially plasma calcium, phosphate, alkaline phosphatase, and zinc, which were normal in all patients. The cause of these skeletal changes is not clear; however, several potential factors need to be considered. Among these are focal marrow expansion in the metaphyseal region due to incomplete suppression of erythropoiesis and possible effects of desferrioxamine, including direct interference with bone growth, altered response of bone to inflammation or infection, and altered bone metabolism related to chelation of trace metals. While we can only speculate on aetiological factors, it is clear that human growth hormone therapy has resulted in exaggeration of deformity due to an increased rate of bone growth or decreased rate of mineralization of physeal cartilage. We believe that bone survey radiographs are useful in early identification of skeletal changes.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Limb deformity and metaphyseal abnormalities in thalassaemia major. 774 45

The increased survival of patients with thalassemia major, made possible by more adequate therapeutic regimens, has emphasized the importance of the endocrine abnormalities often associated with this disease. In twelve thalassemic patients, we evaluated the hypothalamic-pituitary function by measuring plasma levels of anterior pituitary hormones under basal conditions and in the course of provocative tests. An impairment of growth hormone (GH) secretion was demonstrated in a considerable proportion (7/12) of these patients. In some of them failure of GH response to insulin-hypoglycemia and normal hormone rise after growth hormone-releasing hormone indicate a hypothalamic defect. A defective prolactin secretion was observed in the female hypogonadic but not in the male thalassemic patients. This abnormality appears to be dependent on estrogen deficiency rather than on a hypothalamic-pituitary dysfunction. In our series a high prevalence (8/12) of hypogonadism was also noticed. In these cases, the low gonadotropin levels and their unresponsiveness to gonadotropin-releasing hormone are compatible with a hypothalamic and/or pituitary damage. Lastly, the enhanced ACTH responses to the stimuli associated to a reduced cortisol release suggest the existence, in these patients, of a diminished adrenocortical reserve. On the whole, this study has shown several derangements of the hypothalamic-pituitary function in thalassemia. This emphasizes the need for careful endocrine surveillance in this disease.
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PMID:Evaluation of hypothalamic-pituitary function in patients with thalassemia major. 162 77

The effect of long-term human chorionic gonadotropin (HCG) therapy on the linear growth and biological growth parameters was studied in six thalassaemic boys aged 14.5-15.5 years old with hypogonadotropic hypogonadism. A significant (P less than 0.001) increase in growth velocity (from 3.3 +/- 0.3 to 7.6 +/- 0.6 cm/year) was found after 6-12 months of therapy, without acceleration of bone age. A striking improvement in pubertal development was observed. The treatment significantly increased growth hormone (GH) response to L-dopa administration (P less than 0.025) as well as sleep GH secretion (P less than 0.025). Serum growth factors, evaluated as thymidine activity during deep sleep, increased (P less than 0.001), but somatomedin C (Sm-C) levels did not. Prior to treatment, baseline and peak values of plasma growth hormone releasing hormone (GH-RH) following L-dopa were low. After HCG therapy, GH-RH response to L-dopa increased significantly (from 9.2 +/- 5.6 to 20.2 +/- 6.2 pg/ml; P less than 0.05), but remained (P less than 0.001) lower than in normal prepubertal children. This study suggests that in thalassaemia major an impaired GH-RH release can be observed, in addition to the described alteration in Sm-C generation.
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PMID:Effect of human chorionic gonadotropin on growth velocity and biological growth parameters in adolescents with thalassaemia major. 249 61

The growth hormone-releasing hormone (GHRH) test was applied to more than 230 children. Twenty-five out of 61 patients with proven growth hormone (GH) deficiency responded to GHRH with a GH increase of greater than 10 ng/ml. In most of the patients with idiopathic GH deficiency, a priming procedure using daily injections of GHRH improved the secretory response to GHRH. Nearly all children with familial shortness of stature showed a prompt increase in GH levels, with a mean peak level of 34.9 ng/ml (range 0.5-144 ng/ml). A second test was performed in five children with familial short stature because of failure to respond to the first test. Children with constitutional delay of growth and development did not differ in their GH response from patients with familial shortness of stature. Ten girls with Ullrich-Turner's syndrome responded with a mean increase of 22 ng/ml GH (range 10.1-34.0 ng/ml). Therapy with glucocorticoids, as well as endogenous hypersecretion of cortisol, suppressed the responsiveness of the pituitary gland to GHRH. Suppression was also observed following a single dose of dexamethasone during the steroid-suppression test in eight obese children. Low responsiveness of the pituitary gland was also seen in patients with thalassaemia and transfusion-induced haemosiderosis. It is concluded that it is not possible to detect GH deficiency with a single GHRH test. A full endocrinological evaluation is necessary to prove the diagnosis.
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PMID:Diagnostic value of growth hormone-releasing hormone tests in short children. 250 69

Screening of 7500 children aged between 5.8 and 14.4 years, out of a total population of 39,690 in this age group in the Rehovot region, revealed 111 children with heights 2.5 SD below the mean for their age, according to the Tanner-Whitehouse standards. Included among these short children were eight with hypochondroplastic skeletal disease, two with Down's syndrome, four with thalassaemia, four with Turner's syndrome, three with coeliac disease, four with classical growth hormone (GH) deficiency, four with intrauterine growth retardation, four with systemic disease and 78 without obvious underlying causes. In 35 of the 78 children in the last group, the 24-hour integrated concentration of GH was in the hypopituitary range (less than 3.2 ng/ml), and GH neurosecretory dysfunction (NSD) was accordingly diagnosed. This represents an incidence of GH neurosecretory dysfunction of 45% among abnormally short children without underlying pathology, and is consistent with the authors' previous findings. The overall frequency of GH neurosecretory dysfunction in the screened population was 4/1000.
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PMID:Incidence of neurosecretory dysfunction among children aged 6-14 years in Rehovot, Israel. 275 May 34

Basal and L-dopa-stimulated secretion of growth hormone (GH) was investigated in 10 patients with beta-thalassaemia major. Five patients were prepubertal (chronological age 8 to 12 years), whereas 5 patients had delayed puberty (chronological age 15 to 19 years). Ten normal prepubertal subjects (chronological age 8 to 11 years) served as the control group. Each thalassaemic patient was subjected to two L-dopa tests (0.5 g L-dopa plus 0.7 mg/Kg body weight propranolol, orally): one was performed under conditions of low haemoglobin (Hb) levels (30 days after the last blood transfusion), and the second in the presence of increased Hb concentrations (10 days after the transfusion of packed red blood cells). Before the transfusion of packed red blood cells, basal GH concentrations were significantly higher in the patients with delayed puberty (4.3 +/- 1.6 ng/ml), than in prepubertal thalassaemic (1.8 +/- 0.9 ng/ml, p less than 0.05) and control (1.9 +/- 1.0 ng/ml, p less than 0.02) subjects. In contrast, the pituitary responsiveness to L-dopa, expressed as the relative maximum response for GH (GH delta %), was significantly higher in the latter two groups (8.5-fold, p less than 0.05, and 10.9-fold, p less than 0.02, respectively). The transfusion of packed red blood cells increased significantly Hb concentrations in both groups of thalassaemic patients (prepubertal +27%, p less than 0.05, delayed puberty +33%, p less than 0.025, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of increased haemoglobin levels on growth hormone (GH) secretion in beta-thalassaemia major: differences between prepubertal subjects and patients with delayed puberty. 324 42


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