Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Serum ferritin (SF) was determined by an immunoradiometric assay in a heterologous antibody system in 184 children of different ages with and without hematologic or biochemical signs of disturbed iron metabolism. SF levels as determined by this assay were higher than with a homologous antibody system, allowing a reliable discrimination of iron deficiency and overload. In normal children SF increased with age. In latent iron deficiency all SF values were below the normal range, if patients with signs of infections, elevated serum transaminases or parenteral iron therapy were excluded. In anemia of chronic renal failure there was a wider range of values than in controls, especially in children on intermittent hemodialysis. Highest SF values were obtained in polytransfused children with thalassemia. Significant correlations were observed between SF on one hand and Hb, MCV, MCH and serum transferrin saturation on the other hand, except in children with chronic renal failure on conservative treatment. Under hemodialysis there was a significant relation to the number of blood transfusions given.
 ...
PMID:[Serum ferritin in children with disorders of iron balance]. 711 57

Twenty-eight children with beta-thalassaemia major aged between 11 and 48 months were given intensive transfusions. Serum iron, transferrin saturation, serum ferritin, non-transferrin iron, and subcutaneous desferrioxamine-induced urinary iron excretion were measured. The results showed that even children with a limited number of transfusions had severe iron overload as indicated, in particular, by the raised serum ferritin levels and the high excretion rates after subcutaneous infusion of desferrioxamine. The desferrioxamine test was useful, even in very young children, in assessing response to chelation therapy thus enabling such treatment to be started early to prevent harm from iron overload.
 ...
PMID:Early iron overload in beta-thalassaemia major: when to start chelation therapy? 718 22

A non-specific iron fraction, not bound to transferrin, has been looked for in the sera of 42 never-transfused patients with beta-thalassaemia trait, 17 of whom had chronic active hepatitis, negative for HBV infection or alcohol abuse. Non-specific iron was found only in the sera of those patients with beta-thalassaemia trait plus chronic active hepatitis who had complete transferrin saturation, high serum ferritin levels and urinary iron excretion and a high degree of hepatic siderosis. In view of the known toxicity of non-transferrin iron, we suggest that this non-transferrin iron fraction may be responsible for the liver damage in these patients. Furthermore, the positive correlation between the presence and the amount of non-transferrin iron and the levels of serum ferritin suggests that this fraction is a sensitive indicator of iron-induced toxicity when severe iron overload slowly develops in patients with beta-thalassaemia trait even in the absence of any iron administration.
 ...
PMID:Non-specific iron in patients with beta-thalassaemia trait and chronic active hepatitis. 725 13

A pedigree was studied in which five individuals with beta-thalassemia minor were found to have nontransfusional hemochromatosis. Three were children under the age of 10 and two were young male adults, ages 28 and 33. A 5-yr-old child without evidence of thalassemia also had hemochromatosis. Since hemochromatosis is transmitted as an HLA-linked autosomal recessive disorder, HLA haplotypes serve as markers of hemochromatosis alleles. In this pedigree, five identifiable HLA haplotypes were associated with hemochromatosis alleles. Only individuals with two hemochromatosis alleles (homozygosity) had heavy iron loads, whether beta-thalassemia minor was present or not. Individuals with beta-thalassemia minor but without a hemochromatosis allele had normal transferrin saturation. A 65-yr-old man with beta-thalassemia minor and a single hemochromatosis allele had only a minimally elevated transferrin saturation (54%). The presence of beta-thalassemia minor did not appear to accentuate the degree of iron loading expected in individuals homozygous or heterozygous for hemochromatosis alleles. Our findings suggest that nontransfusional hemochromatosis found in association with beta-thalassemia minor is due primarily to homozygosity for hemochromatosis.
 ...
PMID:Coincidental nontransfusional iron overload and thalassemia minor: association with HLA-linked hemochromatosis. 727 12

This study concerns the clinical presentation of all thalassemia major or intermedia in children admitted to out genetics department from January 1978 to December 1979. At electrophoresis and/or globin chain synthesis analysis on column chromatography. All these patients were shown to have homozygous beta(0)-thalassemia. The clinical severity was highly variable, dependent on age at presentation and when the patient first became dependent on transfusions. On the main reasons for this variability may be associated with thalassemia 1 or alpha-thalassemia 2 which have an incidence figure of 13 % in our population and hence also in these patients. Remarkable findings of the clinical and hematological picture were: (a) early spleen enlargement and growth deficiency; (b) MCV and MCH values intermediate between normals and beta-thalassemia heterozygotes; (c) normal mean hemoglobin A2 percentage and corpuscular concentration; (d) frequently increased transferrin saturation and ferritin levels; (e) presentation at age greater than 2 with hemoglobin levels about 9 g/dl usually associated with a milder course.
 ...
PMID:Clinical presentation of thalassemia major due to homozygous beta (0)-thalassemia. 729 Sep 83

We evaluated decreasing deferoxamine-induced urinary iron excretion during intensive chelation therapy in four children with thalassemia. Patients received daily intramuscular or subcutaneous therapy as well as intermittent intravenous infusions of high doses of DFO. Iron excretion fell by more than 80% in three patients and decreased by 45% in the fourth. Ferritin concentrations returned to normal or near normal values in all patients. Serum iron concentration and transferrin saturation steadily declined in one of four patients. Supplemental vitamin C was no longer required for normal vitamin C stores or maximum iron excretion in one patient after 26 months of chelation therapy. Interruption of chelation therapy was not followed by increased iron excretion after resumption of treatment with DFO. Decreasing DFO-induced iron excretion occurs during long-term, intensive chelation therapy, and may be the result of substantial reduction of excessive iron stores rather than of tachyphylaxis or transient depletion of an intracellular chelatable iron pool.
 ...
PMID:Response to long-term deferoxamine therapy in thalassemia. 729 39

Recombinant human erythropoietin (rHuEPO) was given subcutaneously three times per week in an escalating dose from 500 u/kg to 950 u/kg together with ferrous fumarate 305 mg and folic acid 5 mg/d, to 10 patients from four unrelated Arab families with homozygous beta-thalassaemia. Six splenectomized patients showed a mean (+/- standard error) increase in haemoglobin from 7.1 +/- 0.1 to 9.3 +/- 0.1 g/dl (P = 0.0001), in RBC from 4.0 to 5.0 x 10(12)/l (P = 0.0001) and in nucleated RBC from 32 +/- 7 x 10(10)/l to 82 +/- 6 x 10(10)/l while receiving 750 u/kg three times per week which persisted for 4-11 months. In two patients there was no need for further blood transfusions. In three out of four unsplenectomized patients there were no changes in Hb and RBC despite dose escalation. There were no significant changes in MVC, MCH and reticulocyte count, serum bilirubin, LDH, malonyldialdehyde (MDA) and vitamin E levels. After 13 weeks of rHuEPO there was a mean increase in the percentage of F cells from 31 +/- 10% to 86 +/- 6% (P < 0.003) in three splenectomized patients and in one unsplenectomized patient from 56.4% to 80% without changes in the levels of Hb F. Globin chain synthesis ratios did not change in four responding patients. Mean serum iron and transferrin saturation index did not change, whereas mean serum ferritin increased from 299 +/- 45 micrograms/l to 480 +/- 20 micrograms/l (P < 0.001). In seven responding patients an accelerated linear growth was indicated by positive changes in height standard deviation score for chronological age. Side-effects were minimal throughout the treatment period.
 ...
PMID:Sustained increase in haemoglobin and RBC following long-term administration of recombinant human erythropoietin to patients with homozygous beta-thalassaemia. 779 54

Insulin-dependent diabetes mellitus (IDDM) is a frequent complication in patients with beta-thalassaemia major. It is believed to be a consequence of the damage inflicted by iron overload to the pancreatic beta-cell. Liver disorders and genetic influences seem to be additional predisposing factors to diabetes mellitus in patients with beta-thalassaemia. Ethnic variations are frequently reported on prevalence and complications of diabetes mellitus in the beta-thalassaemia patients. We investigated 50 Saudi children (< 15 years) with beta-thalassaemia major and 50 beta-thalassaemia minor, and age- and sex-matched controls for the prevalence of diabetes mellitus, and its relation to hitherto claimed predisposing factors. Fasting blood glucose, plasma insulin level, liver function tests, plasma ferritin, iron, and transferrin were assessed in each patient and glucose tolerance was evaluated. Results in patients with beta-thalassaemia major were compared with those obtained for beta-thalassaemia minor and the controls. The results showed moderate elevation of ferritin level in the majority of the beta-thalassaemia major despite desferroxamine therapy. Either hyperinsulinaemia or hypoinsulinaemia was encountered in the majority of these patients. The prevalence of diabetes mellitus was 6 per cent compared to 2 per cent in the beta-thalassaemia minor and normal children. Impaired glucose tolerance (IGT) occurred at a significantly higher (24 per cent) frequency in the beta-thalassaemia major compared to 2 and 0 per cent in the beta-thalassaemia minor patients and normal controls, respectively. The prevalence of diabetes mellitus was significantly lower in the Saudi thalassaemic patients compared to the results obtained from patients of other ethnic groups reported in literature.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Diabetes mellitus in children suffering from beta-thalassaemia. 780 19

Of the various red cell parameters used for distinguishing iron deficiency anaemia (IDA) from beta-thalassaemia trait BTT, red cell distribution width (RDW), which is an objective measure of the degree of anisocytosis, was examined by us for its discriminating value. RDW was measured in 55 patients of IDA and 56 patients of BTT at presentation with the help of an automated haematology analyser. The mean RDWs in IDA and BTT patients were 18.2 +/- 3.8 and 15.1 +/- 1.2 respectively (P < 0.001). In IDA, RDW showed an inverse relationship with the haemoglobin level (r = -0.543; P < 0.001), while no such correlation was observed in BTT patients. An inverse relation was also observed in IDA between RDW and transferrin saturation (TS). Patients with high RDW had low TS and vice versa. The latter finding, although statistically not significant, suggested that the degree of elevation of RDW in IDA could reflect the severity of iron deficiency. Our study revealed that red cell count, which was significantly higher in BTT patients (P < 0.001), the RDW, and the discriminant function (DF) calculated from these two parameters could be useful in distinguishing IDA from BTT. A RDW above 17.1 strongly suggests the presence of IDA. For RDW below 17.1 the DF can be applied for further discrimination. RDW has the advantage of being obtained directly from the analyser, while DF is a calculated value.
 ...
PMID:Red cell distribution width as a measure of severity of iron deficiency in iron deficiency anaemia. 785 69

Three mouse strains have been evaluated as suitable models for investigations into the pathogenesis of iron-overload syndromes. Mice with hereditary heterozygous alpha-thalassaemia had moderately raised reticulocyte counts, but were not anaemic and showed little, if any, iron loading. In contrast, mice with homozygous beta-thalassaemia showed microcytic anaemia, reticulocytosis and splenomegaly. Iron-loading was marked, progressive with age and mainly confined to the spleen. Liver iron-loading increased until the age of 7-8 weeks, with no further increase over successive weeks. Although intestinal iron absorption was modestly increased due to enhanced mucosal uptake, the majority of the 'excess' liver and spleen iron could be accounted for by re-distribution of iron from the erythrocytic compartment. Homozygous hypotransferrinaemic mice, with approximately 1-2% of normal plasma transferrin levels, were markedly anaemic with hypochromic microcytic erythrocytes. Intestinal iron absorption increased 3-4-fold (predominantly due to changes in mucosal transfer), as compared to wild-type controls and heterozygotes, and was ascertained to be a major factor causing the marked hepatic iron overload. Heterozygous hypotransferrinamic mice, with over half normal plasma transferrin levels and a mild degree of hepatic iron loading, showed very similar characteristics to wild-type controls. Thus, of the three models, hpx/hpx mice showed the greatest enhancement in intestinal iron absorption and net iron-loading and provides a suitable animal model of spontaneous iron-overload. Comparison of iron absorption values between the models suggests that reticulocytes cannot account for the enhanced absorption seen in the hpx/hpx mice.
 ...
PMID:Intestinal iron absorption studies in mouse models of iron-overload. 801 25


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>