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

In the past three years 42 patients with heterozygous beta-thalassemia have been observed in our clinic. This group included 39 foreign and three German patients. A ratio of the MCV and the number of erythrocytes below 14 and normal serum iron level distinguish between the hereditary anemia and iron deficiency anemia. The diagnosis is confirmed by haemoglobin electrophoresis. For recognition of the most frequent type in Europe - the heterozygous beta-thalassemia - the demonstration of an elevated HbA2 level by simple microcolumn technique is sufficient. Ten out of 42 patients have been operated because of cholelithiasis. Five additional persons revealed gall bladder stones by ultrasonography. The high incidence of 36% in relatively young patients probably is due to longstanding hemolysis, which produces usually radiolucent pigment stones. Therefore attempts to dissolve gall bladder stones in patients with thalassemia do not seem to be rewarding.
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PMID:[Diagnosis of heterozygous beta-thalassemia]. 707 13

The effectiveness of the one tube method of osmotic fragility with three buffered solutions (0.32% saline, 0.36% saline, and tyrode) as a screening test for beta-thalassaemia trait was evaluated in several groups of subjects from Greece, Yugoslavia, and Thailand. The results clearly demonstrated that 0.36% saline is the most sensitive and effective solution since it could detect 96 to 100% of heterozygotes with beta-thalassaemia, compared to about 80% with both 0.32% saline and tyrode. However, 0.36% saline gave false positive results in normal subjects and was also positive in haematological disorders which influence osmotic fragility. The screening test with 0.36% saline was applied more precisely in 1371 subjects. The test was false positive in 41 (9.1%) of 455 normal subjects while of 438 confirmed heterozygotes with beta-thalassaemia it was positive in 431 (98%) and negative in only seven (2%). The test was also found to be positive in 80% of patients with iron deficiency anaemia and alpha-thalassaemia trait, in 68% of patients with Hb E trait, in 40% of patients with Hb S trait, and in 78% of heterozygotes with rare haemoglobin variants. The increased sensitivity and effectiveness of 0.36% saline in detecting beta-thalassaemia trait and other disorders influencing osmotic fragility as compared to 0.32% saline and tyrode solutions was also confirmed in a study of 384 unselected schoolchildren.
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PMID:Effectiveness of one tube osmotic fragility screening in detecting beta-thalassaemia trait. 727 19

Oxidative damage to erythrocytes in thalassaemia has been related to generation of free radicals by an excess of denaturated alpha- or beta-globin chains, intracellular iron overload and low concentration of normal haemoglobin (HGB). Two good indicators of such oxidative damage are the high red blood cell (RBC) malonyldialdehyde (MDA) production detected following exogenous oxidant stress and the decrease of pyrimidine 5'-nucleotidase (P5N), the most sensitive enzyme to SH-group damage in vivo. Conflicting data, however, have so far accumulated in the literature concerning differences in oxidative damage between the different forms of thalassaemia and iron deficiency anaemia (IDA). In the present study, oxidative susceptibility, as defined by the production of MDA in vitro and antioxidant capacity, as measured by the activity of RBC glutathione peroxidase (GPx), superoxide dismutase (SOD) and by reduced glutathione (GSH), have been studied in microcytic RBCs from patients with beta-thalassaemia trait, Spanish (delta beta) zero-thalassaemia heterozygotes (delta beta-thalassaemia trait) and iron deficiency anaemia (IDA). The results are consistent with the existence of significant differences in the severity and pattern of oxidative stress susceptibility between beta-thalassaemia trait (increased MDA production and higher SOD and GPx activities) and the other two forms of microcytosis (delta beta thalassaemia trait and IDA). Furthermore, the finding of normal P5' N activity in delta beta thalassaemia trait, gives further support to the less intense peroxidative environment of RBCs in this form of thalassaemia when compared to beta-thalassaemia trait, characterized by acquired RBC P5' N deficiency due to oxidative damage.
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PMID:Increased susceptibility of microcytic red blood cells to in vitro oxidative stress. 749 80

Thalassemia is an autosomal recessive disease characterized by absent or decreased synthesis of the globin chain. This disease is very common in Taiwan area. It mainly consists of alpha- and beta-thalassemia. The diagnosis of these entities depends on hemoglobin electrophoresis, mean corpuscular volume (MCV), or mean hemoglobin concentration of red blood cell and excludes the disease of iron deficiency anemia. However, these tests are not reliable. The definite diagnosis is to check the hemoglobin genes directly. In recent years, we have developed several molecular techniques to solve these problems. This review focuses on the techniques which are used recently in Taiwan area.
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PMID:Molecular diagnosis of thalassemia in Taiwan. 765 Jul 75

Hypochromic and microcytic red cell morphology is the most commonly encountered abnormality in a clinical laboratory. Most of such cases have iron deficiency anaemia. However, in Pakistan about 5% of the individuals with a hypochromic and microcytic blood picture have the beta-thalassaemia trait. These individuals are more than often in a positive iron balance. However iron deficiency (being common) may be associated with the beta-thalassaemia trait. This study of serum ferritin levels was carried out on 135 confirmed cases of the beta-thalassaemia trait. A ferritin assay was done by a radioimmunoassay technique. The results show that the level of serum ferritin in 100 (74%) cases was within normal limits, in 17 (12.6%) cases it was above the normal range, whereas in 18 (13.4%) cases the level was lower than normal. The importance of serum ferritin estimation in carriers of the beta-thalassaemia trait is highlighted.
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PMID:Serum ferritin levels in carriers of beta-thalassaemia trait. 892 1

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.
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PMID:Red cell distribution width as a measure of severity of iron deficiency in iron deficiency anaemia. 785 69

Hemoglobin A2 levels in members of an African American family with -88 C-->T beta(+)-thalassemia were measured, and two patients in whom iron deficiency anemia developed were evaluated during treatment. Iron deficiency may diminish the level of HbA2 in healthy control subjects and in patients with heterozygous beta-thalassemia; in addition, it may reduce the amount of variant hemoglobin in certain hemoglobinopathies. Although iron deficiency appeared to be associated with a reduction in HbA2 quantity in the patient with heterozygous beta-thalassemia, the level of HbA2 did not fall below the range characteristic of beta-thalassemia. It had been proposed that mutations in the beta-globin gene promoter may be associated with higher-than-expected levels of HbA2. However, this "mild" beta-globin gene promoter mutation did not seem to result in HbA2 concentrations higher than anticipated in the heterozygous beta-thalassemias.
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PMID:Case report: effects of iron deficiency and the -88 C-->T mutation on HbA2 levels in beta-thalassemia. 848 91

Because anemia is a condition rather than a disease, an underlying cause must be determined when anemia is identified. Microcytic anemia is a common category of anemia. Iron deficiency anemia is the most common type of microcytic anemia and is also the most common anemia. The clinical presentation of anemia varies according to its severity. Anemias resulting from chronic disease and thalassemia are also relatively common types of microcytic anemia and should be differentiated from iron deficiency to avoid repeated unnecessary trials of iron therapy. Low serum ferritin is the best single laboratory parameter for the diagnosis of iron deficiency. Serum iron, total iron binding capacity and hemoglobin electrophoresis, if necessary, can help differentiate the type of microcytic anemia in patients with normal or elevated levels of serum ferritin. If the evaluation identifies iron deficiency as the type of anemia, the underlying cause must be investigated.
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PMID:Microcytic anemia. 916 44

The present study discusses in detail the osteological changes associated with sickle cell anemia in children and their importance in differential diagnosis. Posterior calcaneal and specific articular surface disruptive metacarpal lesions are diagnostic for sickle cell anemia. Calvarial thickening, tibial and femoral cortical bone thickening, and bowing are of more limited utility in differential diagnosis. Granular osteoporosis, pelvic demineralization and rib broadening are nonspecific. Localized calvarial "ballooning," previously not described, may have diagnostic significance. Bone marrow hyperplastic response (porotic hyperostosis) in sickle cell anemia produces minimal radiologic changes contrasted with that observed in thalassemia and blood loss/hemolytic phenomenon. Two other issues, the osteological criteria for discriminating among the anemias and the purported relationship between porotic hyperostosis and iron deficiency anemia, are also discussed. There is sufficient information to properly diagnose the four major groups of anemias, and further, to establish that iron deficiency is only indirectly associated with porotic hyperostosis. The hyperproliferative bone marrow response (manifest as porotic hyperostosis) to blood loss or hemolysis exhausts iron stores, resulting in secondary iron deficiency.
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PMID:Recognition of sickle cell anemia in skeletal remains of children. 938 28

Serum erythropoietin (sEpo) concentration is primarily related to the rate of renal production and, under the stimulus of hypoxia, increases exponentially as hemoglobin (Hb) decreases. Additional factors, however, appear to influence sEpo, and in this work, we performed studies to evaluate the role of the red blood cell precursor mass. We first compared the relationship of sEpo with Hb in patients with low versus high erythroid activity. The first group included 27 patients with erythroid aplasia or hypoplasia having serum transferrin receptor (sTfR) levels < 3 mg/L (erythroid activity < 0.6 times normal), while the second one included 28 patients with beta-thalassemia intermedia having sTfR levels > 10 mg/L (erythroid activity > 2 times normal). There was no difference between the two groups with respect to Hb (8.3 +/- 1.6 v 8.0 +/- 1.3 g/dL, P > .05), but sEpo levels were notably higher in patients with low erythroid activity (1,601 +/- 1,542 v 235 +/- 143 mU/mL, P < . 001). In fact, multivariate analysis of variance (ANOVA) showed that, at any given Hb level, sEpo was higher in patients with low erythroid activity (P < .0001). Twenty patients undergoing allogeneic or autologous bone marrow transplantation (BMT) were then investigated. A marked increase in sEpo was seen in all cases at the time of marrow aplasia, disproportionately high when compared with the small decrease in Hb level. Sequential studies were also performed in five patients with iron deficiency anemia undergoing intravenous (IV) iron therapy. Within 24 to 72 hours after starting iron treatment, marked decreases in sEpo (up to one log magnitude) were found before any change in Hb level. Similar observations were made in patients with megaloblastic anemia and in a case of pure red blood cell aplasia. These findings point to an inverse relationship between red blood cell precursor mass and sEpo: at any given Hb level, the higher the number of red blood cell precursors, the lower the sEpo concentration. The most likely explanation for this is that sEpo levels are regulated not only by the rate of renal production, but also by the rate of utilization by erythroid cells.
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PMID:Red blood cell precursor mass as an independent determinant of serum erythropoietin level. 949 Jul 1


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