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

Eighty-five cases of beta-thalassemia minor were found between January 1975 and November 1977 in 18 families of French-speaking Quebeckers without Mediterranean ancestry. Most of the families had settled in Quebec more than 200 years ago, largely in Portneuf county. This is the first report of such a number of cases of beta-thalassemia in this population. Thus, beta-thalassemia minor is a relatively common condition in Quebec and must be considered in cases of microcytic anemia without evidence of iron deficiency. The hematologic findings were similar to those reported in the past in other populations. Two cases of delta beta-thalassemia minor (in sisters) are also reported; this is the first report of such cases in French Canadians.
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PMID:[Thalassemia in French-speaking Quebec residents]. 70 70

In a total group of 415 subjects (100 normal controls, 115 with iron deficiency anemia, 100 with the alpha-thalassemia trait, and 100 with the beta-thalassemia trait), the following indexes were analyzed: hemoglobin distribution width, red blood cell distribution width (RDW)-coefficient of variation, and RDW-SD. The hemoglobin distribution width and RDW-coefficient of variation were examined with a laser light scattering system (Technicon H1), whereas the RDW-SD was determined with an impedance autoanalyzer (Sysmex M-2000). All of these parameters helped, to some extent, in the differential diagnosis of microcytic anemia. However, our data suggested a low RDW-SD might provide significantly more value in differentiating thalassemia traits from iron deficiency anemia, as well as from normal controls, while the hemoglobin distribution width gave no help in the differential diagnosis between iron deficiency anemia and the beta-thalassemia trait.
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PMID:Comparison of hemoglobin and red blood cell distribution width in the differential diagnosis of microcytic anemia. 141 42

Microcytic anemia is defined as the presence of small, often hypochromic, red blood cells in a peripheral blood smear and is usually characterized by a low MCV (less than 83 micron 3). Iron deficiency is the most common cause of microcytic anemia. The absence of iron stores in the bone marrow remains the most definitive test for differentiating iron deficiency from the other microcytic states, ie, anemia of chronic disease, thalassemia, and sideroblastic anemia. However, measurement of serum ferritin, iron concentration, transferrin saturation and iron-binding capacity, and, more recently, serum transferrin receptors may obviate proceeding to bone marrow evaluation. The human body maintains iron homeostasis by recycling the majority of its stores. Disruptions in this balance are commonly seen during menstruation, pregnancy, and gastrointestinal bleeding. Although the iron-absorptive capacity is able to increase upon feedback regarding total body iron stores or erythropoietic activity, this physiologic response is minimal. Significant iron loss requires replacement with iron supplements. The vast majority of patients respond effectively to inexpensive and usually well-tolerated oral iron preparations. In the rare circumstances of malabsorption, losses exceeding maximal oral replacement, or true intolerance, parenteral iron dextran is effective. In either form of treatment, it is necessary to replete iron stores in addition to correcting the anemia.
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PMID:Microcytic anemia. Differential diagnosis and management of iron deficiency anemia. 157 56

A four-year-old boy admitted for fever and a skin rash was diagnosed as having a rickettsial infection. Regenerative microcytic anemia and enlargement of the spleen were also found. Hemoglobin electrophoresis and a family study disclosed a combination of two heterozygous hemoglobinopathies, i.e., HbO Arab and beta-thalassemia. A male sibling had the same anomalies as the index patient and was free of symptoms.
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PMID:[Association of Hbo Arab/beta-thalassemia discovered fortuitously in 2 brothers]. 161 42

Hemoglobin (Hb) S/beta(+)-thalassemia is a hemoglobinopathy of variable but potentially severe clinical course. The condition is usually confirmed by the presence of a microcytic anemia and elevated levels of Hbs S, F, and A2 by electrophoresis. However, other less common disorders of Hb structure and synthesis may exhibit laboratory findings that mimic Hb S/beta(+)-thalassemia but have a more favorable prognosis. We present a case occurring in a man with clinical and laboratory features that were suggestive of Hb S/beta(+)-thalassemia but with normocythemia. Although nonmicrocytic variants of beta(+)-thalassemia, including concomitant nutritional deficiencies, were considered, high-pressure liquid chromatography revealed nearly all of the patient's fetal Hb to contain only G gamma chains. This pattern is most consistent with the rate but clinically benign condition of Hb S/G gamma-beta(+)-hereditary persistence of fetal Hb, a nondeletional type of hereditary persistence of fetal Hb. We discuss a diagnostic approach to adult Hb A, F, and S conditions, including thalassemias and thalassemia-like syndromes.
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PMID:Differential diagnosis of adult hemoglobin A, F, and S conditions. A case of G gamma-beta(+)-hereditary persistence of fetal hemoglobin. 170 58

Some routine red blood cell (RBC) measurements and indexes (count, mean volume, volume dispersion, and mean hemoglobin [HGB] concentration) can be used to differentiate iron deficiency from heterozygous beta-thalassemia. A number of formulas that incorporate two or more of these measurements have been described to amplify such differences. The H*1 hematology analyzer directly measures volume and HGB concentration of individual RBCs. We have assessed the diagnostic usefulness of conventional and new RBC measurements provided by the H*1 on a learning data set that comprised 119 patients with iron deficiency and 172 patients with beta-thalassemia trait, both untreated and uncomplicated. The most striking finding was the inverse behavior of percentages of microcytes (volume, less than 60 fL) and hypochromic RBCs (HGB concentration, less than 280 g/L) in the two conditions. In 162 of 172 patients with beta-thalassemia trait, the percentage of microcytes (mean, 33.1%; central 95th percentile range, 9.2% to 54.5%) was higher than the percentage of hypochromic RBCs (mean, 13.9%; central 95th percentile range, 1.7% to 24.7%). In 105 of 119 patients with iron deficiency, on the contrary, the percentage of hypochromic cells (mean, 34.6%; central 95th percentile range, 9.7% to 73.1%) was higher than the percentage of microcytes (mean, 12.8%; central 95th percentile range, 1.7% to 29.6%). The ratio between the percentage of microcytes and the percentage of hypochromic cells provided by the H*1 (microcytic-hypochromic ratio) was useful in differentiating the two types of microcytic anemia: with the use of a discriminant value of 0.9, the discriminant efficiency of the microcytic-hypochromic ratio was 92.4% (95% confidence interval, 88.8% to 95.2%), higher than that of the five previously described discriminant formulas and simple RBC measurements. When assessed on a test data set that comprised 149 unselected cases of microcytic anemia, a microcytic-hypochromic ratio lower than 0.9 demonstrated high sensitivity (94.0%), specificity (92.3%), and predictive value (94.0%) for the presence of iron-deficient erythropoiesis in patients with isolated iron deficiency, polycythemia vera treated by phlebotomy, and iron deficiency complicating heterozygous thalassemia. In conclusion, our results showed that iron-deficient erythropoiesis is characterized by the production of RBCs with a severely decreased HGB concentration, while microcytes of beta-thalassemia trait are generally smaller, with a more preserved HGB concentration. Such properties, as assessed by the H*1 hematology analyzer, are very useful in distinguishing these two common types of microcytic anemia.
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PMID:Automated measurement of red blood cell microcytosis and hypochromia in iron deficiency and beta-thalassemia trait. 173 38

This paper describes the percentile curves for red blood cell (RBC) count, Hb, mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH) values of beta zero-thalassaemia heterozygotes during infancy, childhood and adolescence. Hb values were about 2 g/dl below those of normal controls with a progressive increase with age paralleling the normal developmental trend. The Hb increase with age was due to a progressive rise in the Hb content per cell, the number of RBC remaining nearly constant. MCV and MCH values also increased with age with a pattern parallel to normal control. Because of the high prevalence of alpha-thalassaemia in the Sardinian population, to which all the subjects investigated belong, the 3rd MCH-MCV percentile curves of normal overlap the 97th curve of beta-thalassaemia heterozygotes. The HbA2 levels, however, were always increased as compared to normal. These results confirm in children than screening for heterozygous beta-thalassaemia in populations with a high incidence of alpha and beta-thalassaemia by MCV-MCH determination may overlook a sizeable proportion of beta-thalassaemia carriers. The knowledge of the extent of variation of RBC indices of beta-thalassaemia heterozygotes during infancy, childhood and adolescence, is very useful for the evaluation of a child presenting with a mild microcytic anaemia.
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PMID:Percentile curves for red cell indices of beta zero-thalassaemia heterozygotes in infancy and childhood. 204 Mar 50

The majority of anemias in the United States are characterized by low mean corpuscular volume and thus are classified as microcytic. Iron deficiency, chronic disease and thalassemia traits are the three leading causes of microcytic anemia. The true cause of anemia must always be sought so that the prevalence estimates of iron deficiency are accurate and so that appropriate treatment can be initiated for the anemic individual. In both the clinical setting and in surveys, the most frequent differential diagnosis of microcytic anemia will involve distinguishing between iron deficiency and chronic disease. Erythrocyte sedimentation rate (ESR), zeta-sedimentation rate (ZSR), and C-reactive protein (CRP) are elevated in a variety of diseases. These indicators may help differentiate the anemia of chronic disease from iron deficiency, so that iron deficiency is not overestimated in hospitalized and aged populations. The red cell distribution width (RDW) appears to be elevated to a greater extent in iron deficiency than in chronic disease or thalassemia traits. RDW and CRP are two of several indicators of iron status in the third National Health and Examination Survey (NHANES III).
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PMID:Iron: nutrition monitoring and nutrition status assessment. 224 93

Hereditary HbH disease was found in a Japanese family. The propositus showed hypochromic microcytic anemia and chronic hemolysis. HbH inclusion bodies were detected in red cells, and an abnormal band corresponding HbH was found in an isoelectric focusing of the hemolysate. Gene analysis of the propositus revealed double heterozygosity for alpha + and alpha zero thalassemias. Four of six his siblings shared the alpha zero thalassemia and one the alpha + thalassemia. Another one was normal. The alpha + thalassemia was of 3.7 kb-deletion type and alpha zero was close to Southeast Asian type. This is the fourth Japanese family with hereditary HbH disease.
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PMID:[A Japanese family with hereditary HbH disease--a case report and its gene analysis]. 232 81

To investigate the possible causes of an increased incidence of red cell microcytosis in Asian children, 204 Gujarati Asian children and 88 European children attending community infant welfare clinics underwent initial screening tests for determination of red cell indices. Seventy six Asian (37%) and nine European (12%) children had microcytic red cells (mean corpuscular volume less than 74 fl). Further investigation showed that 16 of the Asian children (21%) with microcytosis had thalassaemia trait (eight were heterozygous for alpha thalassaemia and eight for beta thalassaemia), and 50 (66%) had suspected iron deficiency (confirmed by a response to oral iron in 41 cases): the remaining 'microcytic' children were aged less than 2 years, when mean corpuscular volume between 70 and 74 fl may be normal. Increased values for serum total iron binding capacity were more sensitive in detecting iron deficiency than reduced serum ferritin concentrations. Enthusiastic screening for microcytic anaemia in young children may mean that a substantial minority with thalassaemia genes are given unnecessary iron supplements. The response to a short course of oral iron should therefore be carefully monitored, and the possibility of thalassaemia trait as well as non-compliance with treatment should be reconsidered in all those in whom there is little or no response.
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PMID:Microcytosis, iron deficiency, and thalassaemia in preschool children. 237 18


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