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

Heterozygous beta thalassaemia with microcytic anaemia (hemoglobin concentration 77 g/l) has been recognized in a 49 year-old woman of Alsatian extraction. A long history of microcytic anaemia had led to inadequate oral iron treatment before the patient was referred to us because of the persisting microcytic anaemia and iron loading. Indeed the patient also had haemosiderosis with a high transferrin saturation (73%) and markedly elevated ferritinaemia (1,114 micrograms/ml). Ferrokinetic data showed increased plasma iron turnover, early transfer of iron to the liver and evidence of ineffective erythropoiesis. She was treated with desferrioxamine (3 g every three days subcutaneously) and serum ferritin levels gradually decreased together with transferrin saturation. After 15 months serum ferritin and transferrin saturation were within the normal range. Several hypotheses are discussed to explain why this patient had haemosiderosis associated with heterozygous beta thalassaemia. The propositus was found to be HLA-A3, which is strongly associated with idiopathic haemochromatosis. Her sister also carries HLA-A3 with heterozygous beta thalassaemia but she has neither anaemia nor iron overload. Thus double heterozygotism is unlikely in our patient.
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PMID:[Iron overload in a beta thalassemia heterozygote of the intermediate type in a subject of Alsation origin. Results of iron chelation treatment]. 633 73

Erythrocyte protoporphyrin (EP) was measured in 50 normal control subjects, 22 iron-responsive anemic subjects, and in 106 patients with thalassemic diseases. All normal subjects had EP of less than 80 micrograms/dL red blood cells, whereas all iron-deficiency subjects had EP of more than 80 micrograms/dL red blood cells. Six of 22 heterozygotes for thalassemias had elevated EP, and all of these had transferrin iron saturation of less than 16%, reflecting a complicating iron deficiency. Among 52 patients with beta-thalassemia/hemoglobin (Hb) E disease, 26.9% had elevated EP levels, and among 32 patients with Hb H disease, 40.6% had elevated EP. These elevated EP levels were associated with transferrin iron saturation between 18 and 44%. In none of the thalassemic patients with transferrin iron saturation above 44% was EP elevated. These findings suggest that elevation of EP in some thalassemic patients causally is related to iron supply inadequate for the massively expanded erythropoiesis. This relative iron deficiency in thalassemia occurs at a transferrin iron saturation level usually considered to be normal. These relationships demonstrate the need for an increased iron supply in patients with erythroid marrow hyperplasia, if erythropoiesis is to proceed at maximal rates.
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PMID:Increased red blood cell protoporphyrin in thalassemia: a result of relative iron deficiency. 646 95

Serum transferrin concentrations and total iron-binding capacities were measured in 184 adult male subjects using standard biochemical methods. The haemoglobin phenotypes of these subjects were also established. Decreases in both of these parameters were observed when HbAE, beta-thalassaemia trait (raised level of HbA2), and HbEE subjects were compared to HbA subjects. Though the decrease was slight in the cases of HbAE and beta-thalassaemia trait, HbEE subjects had significantly reduced values. Both the parameters were also significantly reduced when values from HbEE subjects were compared to those from HbAE and beta-thalassaemia trait. It is suggested that marginal liver damage is present in subjects with homozygous HbE, leading to a reduction in transferrin production.
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PMID:Serum transferrin concentrations and total iron-binding capacities in relation to different haemoglobin phenotypes. 651 15

Up until recently in clinical practice suspected hemochromatosis with a pathological iron-screening test (plasma iron, percentage transferrin saturation, serum ferritin, desferrioxamine-induced urinary iron excretion) made a liver biopsy necessary. Today, as a first step, the density of the liver parenchyma can be measured by means of computed tomography. Normal findings obviate the need for laparoscopy. Since the late forties weekly or twice weekly phlebotomy has been the sole form of treatment for manifest idiopathic hemochromatosis. In the mid-sixties the hopes placed in chelating substances (desferrioxamine) were not fulfilled, because the plasma half-life (only 7-10 minutes) of this drug was too short. Even with several daily injections only a small amount of iron was removed from the body tissue (10-25 mg daily urinary iron excretion). The introduction of portable infusion pumps in the late seventies offered us a new possibility of administering desferrioxamine by subcutaneous injection (Propper et al., 1976). Until that time such treatment was successfully used only in the field of pediatrics to treat secondary transfusion hemochromatosis in thalassemia. In one case of idiopathic hemochromatosis with severe organic involvement (right heart failure, repeated esophageal hemorrhage and bronzed diabetes) we had to achieve rapid iron elimination, and for this purpose we used continuous long-term desferrioxamine administration by means of a portable infusion pump (Autosyringe) in addition to phlebotomy. Since, particularly in the critical initial phase of treatment when heart failure was always threatening, great care had to be exercised in the use of phlebotomy, iron removal was achieved largely by desferrioxamine administration (daily up to 240 mg iron elimination in urine and stools).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:New diagnostic and therapeutic possibilities in manifest idiopathic hemochromatosis. 651 41

The effect of transferrin absence on in vitro globin chain synthesis and on the alpha/beta ratio were investigated in four patients with beta-thalassemia intermedia and one heterozygote with "silent" beta-thalassemia. With one exception the lack of transferrin in the incubation medium resulted in the reduction of the globin alpha/beta ratio which paralleled a reduction in overall protein synthesis. In one patient with beta-thalassemia intermedia, however, the absence of transferrin failed to affect this ratio.
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PMID:Effect of transferrin absence on in vitro globin chain synthesis in reticulocytes of beta-thalassemic patients. 661 87

Non-transferrin plasma iron concentrations were determined in 45 normal controls and in 37 patients with Hb H disease and 104 patients with beta-thalassaemia/Hb E disease. This revealed that non-transferrin plasma iron exists in cases with severe iron overload, more striking in beta-thalassaemia/Hb E than in Hb H disease. Non-transferrin plasma iron is associated with higher transferrin iron saturation and higher plasma ferritin levels. The most striking finding was the significantly higher non-transferrin plasma iron in splenectomized patients with beta-thalassaemia/Hb E disease than in the non-splenectomized patients. In view of the potential toxicity of non-transferrin iron, this fraction of iron may be responsible for tissue damage in these patients especially after splenectomy.
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PMID:Non-transferrin plasma iron in beta-thalassaemia/Hb E and haemoglobin H diseases. 670 60

Some parameters of iron metabolism in 26 patients with porphyria cutanea tarda (PCT) which is often associated with mild iron overload and hepatic siderosis, are studied. Serum iron, percent transferrin saturation and ferritin were pathologically increased. Statistical comparisons were performed between PCT patients and healthy controls, liver disease patients (cirrhosis, chronic active hepatitis) and patients with associated liver siderosis (alcoholic cirrhosis, cirrhosis and chronic active hepatitis in thalassemia). Ferritin levels are higher in patients with porphyria than in healthy controls (p less than 0,001) and in patients without liver siderosis (p less than 0,001). No statistical difference is observed between patients with porphyria and patients with siderosis. A significant decrease in ferritin levels is registered after venesection therapy. The conclusion is drawn that serum ferritin increase in PCT is related to hepatic iron store amounts rather than hepatic necrosis. It is assumed that ferritin follow-up during phlebotomy therapy and also during remission is useful to indicate the exhaustion or an early replenishment of hepatic iron stores.
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PMID:[Determination of serum ferritin in porphyria cutanea tarda. A reliable sign of hepatic siderosis]. 670 23

Iron overload is a constant and the more important complication in thalassemia. Serum ferritin concentration accurately reflects body iron stores. A total of 245 thalassemic patients aged 12-55 years were examined, 71 having Hb H disease and 174 beta-thalassemia/Hb E disease. The patients received minimal or no blood transfusions. 73 patients with beta-thalassemia/Hb E were studied 1-28 years after splenectomy. The serum ferritin levels in both Hb H and beta-thalassemia/Hb E patients were higher than normal. They were higher in beta-thalassemia/Hb E than Hb H disease. Most striking was the significantly higher serum ferritin levels in splenectomized patients with beta-thalassemia/Hb E disease than in the nonsplenectomized ones. The observation is compatible with previous observations that splenectomy in thalassemia is associated with increased iron deposition and increased transferrin iron saturation. The further increase in iron overload after splenectomy in thalassemia should be borne in considering removal of this organ.
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PMID:Serum ferritin levels in thalassemias and the effect of splenectomy. 680 Jan 90

Microcytic red blood cells (RBC) are commonly encountered in clinical medicine and are caused by disorders of heme synthesis [usually iron deficiency anemia (IDA) or anemia of chronic disease (ACD)] or disorders of globin synthesis (usually thalassemia syndromes or HbE). Using the clinical history and standard laboratory tests (hematocrit, per cent saturation of transferrin (% sat), serum ferritin, Hb electrophoresis, HBA2, and HbF) we classified 198 adults with microcytic RBC as follows: 48 IDA, 11 probable IDA, 11 iron-deficient erythropoiesis without anemia, 13 ACD, 42 alpha-thalassemia trait, 35 probable alpha-thalassemia trait, 20 beta-thalassemia trait, and 15 unclassified. In addition, we demonstrated that the FEP test reliably (83-90% of the time, depending on FEP methodology) classifies microcytic RBC states into disorders of heme synthesis vs. disorders of globin synthesis. Because of reliability and ease of measurement, we recommend the hematofluorometer FEP as the first step in the clinical laboratory evaluation of microcytic RBC disorders in both adults and children.
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PMID:Free erythrocyte protoporphyrin (FEP) II. The FEP test is clinically useful in classifying microcytic RBC disorders in adults. 684 56

Ferritin, iron, total iron binding capacity and transferrin saturation were measured in the serum of 247 patients with microcytic hypochromic anemia. Differentiation into various categories of microcytic hypochromic anemia was based on clinical criteria and on the response to iron treatment. This produced 147 patients with iron deficiency anemia, 35 patients with anemia secondary to infection, 27 patients with anemia due to tumor and 38 patients with thalassemia. Analysis of the iron parameters revealed the reliability of both serum ferritin and transferrin saturation in distinguishing between the various forms of anemia. However, measurement of serum ferritin is slightly more reliable and much less expensive than determination of transferrin saturation.
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PMID:[The value of serum ferritin, serum iron and iron-binding capacity in the differential diagnosis of microcytic hypochromic anemia]. 705 13


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