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

To investigate the development of diabetes mellitus in patients with thalassemia major, plasma glucose and immunoreactive insulin (IRI) levels following oral glucose and intravenous tolbutamide and glucose disappearance rates following intravenous insulin were measured in 10 patients before and during five years on a high transfusion program (HTP). Plasma immunoreactive glucagon (IRG) levels following oral glucose, intravenous insulin, and arginine were measured during the sixth year. Serial percutaneous liver biopsies were performed on seven patients. The oral glucose tolerance tests (OGAT) and mean peak IRI levels were normal in nine of 10 patients before HTP. After HTP was begun a progressive deterioration of OGTT occurred despite normal IRI levels. Following tolbutamide, the mean per cent fall in plasma glucose in the patients before HTP was significantly less than in controls (p less than 0.01) and similar to that of controls during five years of HTP in spite of higher than normal peak IRI levels. Of seven survivors after six years of HTP, three had normal OGTT and four had chemical diabetes; mean peak IRI levels were normal, but fasting IRG levels were significantly higher than in controls (p less than 0.05). In all seven patients, plasma IRG failed to increase following insulin-induced hypoglycemia and was significantly higher than in controls after arginine (p less than 0.01); after oral glucose, plasma IRG fell significantly below that of fasting only in the patients with chemical diabetes (p less than 0.03). Following intravenous insulin, the mean per cent fall in glucose before and during HTP was significantly less than in controls (p less than 0.01). Hemosiderosis and cirrhosis were present in all biopsied patients. Four patients died; two had chemical and two had nonketotic insulin-dependent diabetes. These data suggest that diabetes mellitus occurs frequently in patients with thalassemia on HTP and that insulin resistance and hyperglucagonemia, possibly due to cirrhosis, are important etiologic factors.
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PMID:Carbohydrate metabolism and pancreatic islet-cell function in thalassemia major. 32 76

An increased incidence of diabetes mellitus and glucose intolerance has been reported in thalassaemia major treated with a high transfusion programme (HTP). To investigate beta-cell function, serum immunoreactive insulin (IRI), C-peptide (CP) and glucose were measured fasting and at 3, 6 and 10 min after i.v. administration of 1 mg glucagon in 20 thalassaemia patients treated by many transfusions and in nine healthy control subjects. Fasting C-peptide concentrations (mean +/- SEM) were higher in the thalassaemic group (2.15 +/- 0.17 ng/ml) than in the controls (1.41 +/- 0.13 ng/ml). After stimulation with glucagon, C-peptide concentrations were consistently higher (P less than 0.01) by approximately 50% in the thalassaemic than in the control group (5.29 +/- 0.31 vs 3.36 +/- 0.21 ng/ml, at 3 min; 5.22 +/- 0.30 vs 3.53 +/- 0.21 ng/ml at 6 min and 4.69 +/- 0.27 vs 3.30 +/- 0.17 ng/ml after 10 min). Plasma IRI concentrations increased in both groups after glucagon stimulation but were not significantly different. The glucose values were approximately 15% higher at each sampling time in the thalassaemic group than those of the normal subjects. It is concluded that disturbances in carbohydrate metabolism in thalassaemia major treated with HTP are the consequence of hepatic cirrhosis which accompanies secondary haemosiderosis, and possibly iron deposition in the beta-cells of the pancreas.
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PMID:A study of beta-cell function after glucagon stimulation in thalassaemia major treated by high transfusion programme. 332 97

Insulin and glucagon secretion were studied during an oral glucose tolerance test and arginine infusion in 11 patients with thalassaemia intermedia, who showed laboratory evidence of iron overload. Mean blood glucose concentrations in patients with thalassaemia intermedia were significantly higher than normal and 3 of 11 patients had impaired glucose tolerance. The principal abnormality appears to be a deficiency in insulin and glucagon from the pancreas in response to oral glucose tolerance and arginine stimulation tests. Several factors, such as iron overload, chronic hypoxia, zinc deficiency and increased catecholamine production secondary to anaemia, might play a part in the pathogenesis of these abnormalities. Each of these factors affect individual cases to a varied degree. Our data emphasize the mildness of carbohydrate defect as compared to the degree of insulinopenia and indicate the necessity for prescribing measures which prevent excessive iron deposition and improve iron excretion in thalassaemic patients with iron overload.
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PMID:Alpha and beta cell evaluation in patients with thalassaemia intermedia and iron overload. 390 15

Disturbances of growth and development in patients with thalassaemia receiving hypertransfusion programmes are well recognised and are most likely to be due to iron overload. The extent of endocrine dysfunction was investigated in a group of 18 patients thought to have been treated by acceptable modern standards, 11 of whom could be considered as well chelated. Assessment of growth and puberty showed a wide variation in height SD scores with five patients having significantly short stature. Most patients are progressing through puberty normally with the exception of two boys with marked pubertal delay. The most prominent finding was that growth hormone responses to glucagon stimulation were significantly impaired in all of the patients with iron overload. Basal endocrine assessment showed primary hypothyroidism in two patients aged 16.8 and 12.9 years with plasma thyroxine-concentrations of 86 and 59 nmol/l (normal range 65-165 nmol/l) and plasma thyroid stimulating hormone 10.2 and 30.3 mU/l (normal range 0.5-5 mU/l). One patient had diabetes mellitus. These results show that even when ideal management is sought a significant amount of endocrine damage occurs; surveillance of these patients is thus essential.
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PMID:Relationship of endocrinopathy to iron chelation status in young patients with thalassaemia major. 794 32

The causes of growth retardation of children with thalassaemia major are multifactorial. We studied the GH response to provocation by clonidine and glucagon, measured the circulating concentrations of insulin, IGF-I, IGF-binding protein-3 (IGFBP-3) and ferritin, and evaluated IGF-I generation after a single dose of GH (0.1 mg/kg per dose) in 15 prepubertal patients with thalassaemia, 15 age-matched children with constitutional short stature (CSS) (height standard deviation score less than -2, with normal GH response to provocation) and 11 children with isolated GH deficiency (GHD). Children with thalassaemia had significantly lower peak GH response to provocation by clonidine and glucagon (6.2 +/- 2.3 and 6.8 +/- 2.1 microg/l respectively) than the CSS group (18.6 +/- 2.7 and 16.7 +/- 3.7 microg/l respectively). They had significantly decreased circulating concentrations of IGF-I and IGFBP-3 (47.5 +/- 19 ng/ml and 1.2 +/- 0.27 mg/l respectively) compared with those with CSS (153 +/- 42 ng/ml and 2.06 +/- 0.37 mg/l respectively), but the IGF-I and IGFBP-3 concentrations were not different from those with GHD (56 +/- 25 ng/ml and 1.1 +/- 0.32 mg/l respectively). These data demonstrate that the GH-IGF-I-IGFBP-3 axis in thalassaemic children is defective. Serum ferritin concentration correlated significantly with GH peak response to provocation (r = -0.36, P < 0.05) and circulating IGF-I (r = -0.47, P < 0.01) and IGFBP-3 (r = -0.42, P < 0.01) concentrations. In the IGF-I generation test, after GH injection, the thalassaemic children had significantly lower IGF-I and IGFBP-3 levels 86.7 +/- 11.2 ng/ml and 2.05 +/- 0.51 mg/l respectively) than those in the CSS group (226 +/- 45.4 ng/ml and 2.8 +/- 0.43 mg/l respectively). The IGF-I response was significantly higher in children with GHD (158 +/- 50 ng/ml) than in thalassaemic children. Six short (height standard deviation score less than -2) thalassaemic children who had defective GH response to provocation (< 10 microg/l), all the children with GHD and eight short normal children (CSS) were treated for 1 year with human GH (18 units/m2 per week divided into daily s.c. doses). After 1 year of GH therapy there was a marked acceleration of growth velocity in both thalassaemic children (from 3.8 +/- 0.6 cm/year to 7.2 +/- 0.8 cm/year) and controls. However, the linear acceleration of growth velocity on GH therapy was significantly slower in thalassaemic children (3.3 +/- 0.3 cm/year increment) compared with those with CSS (5.3 +/- 0.4 cm/year increment) and GHD (6.9 +/- 1.2 cm/year increment) (P < 0.05). Their circulating IGF-I concentration (105 +/- 36 ng/ml) was significantly lower than those for CSS (246 +/- 58 ng/ml) and GHD (189 +/- 52 ng/ml) after 1 year of GH therapy. These data prove that some children with beta-thalassaemia major have a defective GH-IGF-I-IGFBP-3 axis and suggest the presence of partial resistance to GH.
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PMID:GH response to provocation and circulating IGF-I and IGF-binding protein-3 concentrations, the IGF-I generation test and clinical response to GH therapy in children with beta-thalassaemia. 957 6

Patients with beta-thalassemia major (beta-thalassemia) frequently have bone disorders of multifactorial etiology. We attempted to analyze the relationship between the bone mineral density ([BMD] measured by dual-photon absorptiometry) and auxanologic parameters, degree of siderosis, function of the growth hormone (GH)/insulin-like growth factor-I (IGF-I)/IGF-binding protein-3 (IGFBP3) axis, calcium-phosphate balance, parathyroid hormone (PTH), and cytokines (interleukin-1beta [IL-1] and tumor necrosis factor-alpha [TNF-alpha]) in 30 prepubertal children with beta-thalassemia major and 15 age-matched children with constitutional short stature (CSS), who have normal glucose tolerance and thyroid function. Children with beta-thalassemia had a significantly decreased BMD and mean BMD% for age and sex (0.75+/-0.24 g/cm2 and 71%+/-10%, respectively) versus children with CSS (1.06+/-0.3 g/cm2 and 92%+/-7%, respectively). Thalassemic patients had significantly lower circulating concentrations of IGF-I and IGFBP3 (49+/-21 ng/mL and 1.2+/-0.25 mg/L, respectively) compared with control children (153+/-42 ng/mL and 2.1+/-0.37 mg/L, respectively). The GH response to provocation by clonidine and glucagon was defective (peak GH < 7 microg/L) in 12 of the 30 thalassemic children. Serum concentrations of IL-1beta and TNF-alpha did not differ among the two study groups. Hypocalcemia was detected in five of the 30 thalassemic patients: hypoparathyroidism was diagnosed in two of the five and rickets in the other three. BMD was highly correlated with the circulating concentrations of IGF-I and IGFBP3, as well as with the auxanologic parameters (age, weight, height, height standard deviation score [HSDS], and body mass index [BMI]). It is suggested that increasing the circulating IGF-I concentration through aggressive nutritional therapy and/or GH/IGF-I therapy with supplementation with vitamin D and/or calcium might improve bone growth and mineralization and prevent the development of osteoporosis and consequent fractures in these patients. Such therapy requires blinded controlled trials.
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PMID:Bone mineral density in prepubertal children with beta-thalassemia: correlation with growth and hormonal data. 959 44

Thalassaemic patients with diabetes mellitus are at risk of developing retinopathy. To evaluate the prevalence and the characteristics of diabetic retinopathy in thalassaemics we examined 46 patients with beta-thalassaemia major and insulin-dependent diabetes by fluorescein angiography. The study group was matched for sex, age and diabetes duration with a control group of 46 type 1 diabetic patients. Diabetic retinopathy was detected in 26% (12/46) of thalassaemics and in 50% (23/46) of the controls. In thalassaemics the diabetic retinopathy was significantly less severe than in controls (P < 0.0001). The influence of risk factors for diabetic retinopathy (duration of diabetes and metabolic control) was confirmed in the control group. In thalassaemic patients we found no significant correlation between these risk variables and the presence of diabetic retinopathy. Various factors may protect thalassaemics from diabetic retinopathy: heterogeneity of pancreatic functions; high incidence of hypogonadism; contemporary dysfunction of GH and/or glucagon secretion.
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PMID:Prevalence of retinopathy in diabetic thalassaemic patients. 1009 Nov 61

Growth retardation in children with thalassaemia major is multifactorial. We studied the growth hormone (GH) response to provocation by clonidine and glucagon, measured the circulating concentrations of insulin, insulin-like growth factor-I (IGF-I), IGF-binding protein-3 (IGFBP3), and ferritin, and evaluated the spontaneous nocturnal (12 h) GH secretion in prepubertal patients with thalassaemia and age-matched children with constitutional short stature (CSS) (height SDS < -2, but normal GH response to provocation). The anatomy of the hypothalamic pituitary area was studied in patients with abnormal GH secretion using MRI scanning. Children with thalassaemia had significantly lower peak GH response to provocation by clonidine and glucagon (8.8 +/- 2.3 micrograms/l and 8.2 +/- 3.1 micrograms/l respectively) than did controls (17.6 +/- 2.7 micrograms/l and 15.7 +/- 3.7 micrograms/l respectively). They had significantly decreased circulating concentrations of IGF-I and IGFBP3 (68.5 +/- 19 ng/ml and 1.22 +/- 0.27 mg/l respectively) compared to controls (153 +/- 42 ng/ml and 2.16 +/- 0.37 mg/l respectively). Seven of the thalassaemic children had a GH peak response of < 7 micrograms/l after provocation. Those with a normal GH response after provocation also had significantly lower IGF-I and IGFBP3 concentrations than controls. Analysis of their spontaneous nocturnal GH secretion revealed lower mean (2.9 +/- 1.77 micrograms/l) and integrated (2.53 +/- 1.6 micrograms/l) concentrations compared to controls (4.9 +/- 0.29 micrograms/l and 5.6 +/- 0.52 micrograms/l respectively). Five of them had mean nocturnal GH concentration < 2 micrograms/l and four had maximum nocturnal peak below 10 micrograms/l. These data denoted defective spontaneous GH secretion in some of these patients. MRI studies revealed complete empty sella (n = 2), marked diminution of the pituitary size (n = 4), thinning of the pituitary stalk (n = 3) with its posterior displacement (n = 2), and evidence of iron deposition in the pituitary gland and midbrain (n = 7) in those patients with defective GH secretion (n = 9). Serum ferritin concentration was correlated significantly with the circulating IGF-I (r = -0.47, p < 0.01) and IGFBP3 (r = -0.43, p < 0.01) concentrations. These data prove a high prevalence of defective GH secretion in thalassaemic children associated with structural abnormality of their pituitary gland.
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PMID:Spontaneous and provoked growth hormone (GH) secretion and insulin-like growth factor I (IGF-I) concentration in patients with beta thalassaemia and delayed growth. 1066 1