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

Three formulae have been advocated for interpreting the blood-count when differentiating between iron deficiency and heterozygous thalassaemia: the discriminant function. M.C.V.-R.B.C.-(5 X Hb)-k, the M.C.V/R.B.C. ratio, and the (M.C.V.)2 X M.C.H. product. In a comparison of their diagnostic accuracy in microcytic adults from several countries, the discriminant function was the most satisfactory. 417 of 455 uncomplicated cases (91.6%) of iron deficiency, heterozygous alpha1- and beta- thalassaemia were correctly identified. The function was not able to distinguish heterozygous alpha2-thalassaemia from iron deficiency. A flow chart illustrates how the discriminant function can be used in haematological practice.
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PMID:Discrimination between iron-deficiency and heterozygous-thalassaemia syndromes in differential diagnosis of microcytosis. 8 63

Two conditions are liable to lower the alpha:beta globin biosynthesis ratio in reticulocytes: iron deficiency and alpha-thalassaemia. The present paper studies the effect of haemin on reticulocytes from 12 patients who have alpha-thalassaemia and/or are iron deficient. The alpha:beta globin biosynthesis ratio was improved in all these cases. 4 showed initially an alpha:beta synthesis ratio usually associated with alpha-thalassaemia type-1; on the addition of haemin the ratio rose to that associated with alpha-thalassaemia type-2. In the other 8 patients the ratio was initially typical for alpha-thalassaemia type-2, and on addition of haemin the ratio became normal. It is suggested that in iron deficient patients a diagnosis of alpha-thalassaemia type-1 or type-2 cannot be made unless haemin has been added to the test system. If this is not done iron deficiency alone can cause the alpha:beta globin synthesis ratio to resemble that associated with alpha-thalassaemia type-2, and iron deficiency in combination with alpha-thalassaemia type-2 can cause the ratio to resemble that typical for alpha-thalassaemia type-1. Reticulocytes from 8 alpha-thalassaemic patients without iron deficiency did not show a marked haemin effect (less than 5%), and in 1 patient with iron overload, the ratio actually fell by about 10%.
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PMID:Interaction between iron deficiency and alpha-thalassaemia: the in vitro effect of haemin on alpha-chain synthesis. 9 95

The value of serum ferritin and mean corpuscular volume (MCV) measurement in distinguishing between iron deficient, beta-thalassaemia trait and normal subjects has been studied. Normal subjects had normal ferritin and MCV, iron-deficient ones had low ferritin and low or normal MCV, and thalassaemics had normal ferritin and low MCV. By the combined use of these two measurements it was possible to identify individuals belonging to one of the three categories with an accuracy of over 95%. Although definitive diagnosis of beta-thalassaemia trait requires the demonstration of abnormal haemoglobin A2 levels or reduced beta-chain synthesis, serum ferritin and MCV measurements are useful screening procedures for the initial diagnosis of beta-thalassaemia trait and iron deficiency. Because of the very small amounts of blood required for both of these measurements, they are particularly suitable for surveying large numbers of subjects in populations with a high prevalence of hypochromic-microcytic anaemias.
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PMID:Serum ferritin and mean corpuscular volume measurement in the diagnosis of beta-thalassaemia minor and iron deficiency. 11 17

Lateral X-ray pictures of the skull in certain several and chronic disorders of the blood as thalassaemia, congenital haemolytic anaemia, sickle cell anaemia and iron deficiency disease show frequently changes of the outlines of the cranial bones. They consist of a double contour of the outer cranial border and on the interior side below the sagittal sutura of a band-like shadow or of multiple stripes and lines running parallel to the carnial vault. They concern the parietal bones and may extend from the bregma till to the lamda or occupy only a part of this distance. The roentgenological features are due to the enlargement of the crainal bones, the bulging out of both parietal bondes, the sometimes enlarged and deepened borders of the sulcus sagittalis superior and particularly to the furrow and depression on the skull above the sagittal suture caused by the protruding parietal bones on both sides. As these different abnormal structures must be passed by the picturing X-ray, effects of superposition and interference are produced. Longitudinal ridges or bony edges which could explain the roentgenological findings could not be established. Since the peculiar alterations of the cranial bones are mainly found in the mentioned blood disorders, where they are caused by the overgrowing red marrow, they also display the same roentgenological features. These features are, therefore, a characteristic sign of these diseases.
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PMID:[Double contours and companion shadows in the skull associated with anaemias (author's transl)]. 15 80

The analysis of cord blood samples of 198 African newborns and their mothers confirmed the high prevalence of iron deficiency. A hypochromia and microcytosis of red cells was found in 40% of the pregnant women at term. In the majority of newborns the haemoglobin concentration was below 16 g/100 ml. Hb S was found in 11%, Hb C in 9% and alpha-thalassaemia in 2% of the population examined. Haemoglobin, packed cell volume and mean cell volume of erythrocytes were lower than results of newborns from developed countries. Foetal sex had no influence on haematological variables.
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PMID:Haematological data of African newborns and their mothers in Abidjan. 21 78

Clinical and haematological features in 41 patients with sickle cell-beta0 thalassaemia (Sbeta0 thalassemia) and in 123 age--sex matched controls with homozygous sickle cell (SS) disease were compared. Persistence of splenomegaly was more common and fetal loss less common in Sbeta0 thalassemia but other clinical features were similar in the two genotypes. Total haemoglobin, Hb A2, PCV, CCV, and red cell count were significantly higher and MCV, MCH, MCHC, and ISC counts significantly lower in Sbeta0 thalassaemia. Proportional reticulocyte counts were significantly lower in Sbeta0 thalassaemia but there was no difference in absolute reticulocyte counts. Persistence of splenomegaly and low ISC counts are compatible with decreased intravascular sickling which may result from the lower mean cell haemoglobin S concentration in Sbeta0 thalassaemia. If beneficial effects of a low MCHC can be confirmed then a carefully monitored trial of iron deficiency in SS disease may be a logical experimental procedure.
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PMID:Comparison of sickle cell-beta0 thalassaemia with homozygous sickle cell disease. 42 Jul 38

The influence of malaria on HbA2 levels was investigated in two groups of children aged two to nine years from the Mano tribe of northern Liberia. One group, 174 children living in a town where there is malaria control, had a parasite rate of 6.5%, only a few having palpable spleens, but 282 children living in an area of intense malaria transmission had a parasite rate of 92%. All but one child in this group had enlarged spleens. However, the difference in proportions of elevated HbA2 values within the limits for beta-thalassaemia, 8% and 10.3% respectively, was not statistically significant (0.5 greater than P greater than 0.1). It was concluded that the influence of malaria on HbA2 levels is not significant and that this parameter is valid for detecting beta-thalassaemia trait in this population. Further, iron deficiency may be a more important factor than malaria to consider when assessing the results of HbA2 estimations.
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PMID:Malaria and haemoglobin A2 levels in northern Liberia. 47 9

A total of 4939 apparently healthy Fijian and Indian subjects living in Fiji were tested for anaemia by determination of the microhaematocrit of a sample of capillary blood. The prevalence of anaemia during childhood varied with age but was similar for Fijians and Indians of either sex. The overall prevalences were: 0-4 years, 20.3%; 5-9 years, 3.7%; 10-14 years, 23.5%. The prevalence of anaemia among Indian women (33.3%) was substantially higher than that for Indian men (6.9%), Fijian women (8.1%) or Fijian men (6.8%). Iron deficiency was the most common cause of anaemia and was established by laboratory studies in 203 (68%) of 298 anaemic subjects who were followed up. Iron deficiency was an important aetiological factor in 91 (93%) of 98 subjects with moderate or severe anaemia. Folate deficiency was found, usually in combination with iron deficiency, in 44 or 141 anaemic indian adults were followed up. Folate deficiency was uncommon in Fijian adults and among children of either race. Two cases of nutritional vitamin B12 deficiency, one case of pernicious anaemia, 6 cases of heterozygous thalassaemia and one case of heterozygous haemoglobin E were found among the anaemic Indian subjects. No cases of vitamin B12 deficiency anaemia, thalassaemia or haemoglobinopathy were detected among the Fijians. In 5 Indians and 7 Fijians the anaemia was associated with an underlying chronic disorder. This study emphasizes that in Fiji, as in other developing countries, nutritional anaemia is prevalent among asymptomatic subjects. Iron deficiency is by far the most common cause.
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PMID:The prevalence and nature of anemia among apparently normal subjects in Fiji. 52 78

The sickle-cell gene contributes substantially to the presentation of anaemia in certain areas of the Arabian Peninsula. However, the clinical presentation of the homozygous state of Hb S is less severe than that observed in other ethnic groups, such as American negroes. In the present paper, biosynthesis studies performed on reticulocytes from heterozygotes and homozygotes for the Hb S give further indications of the mild nature of sickle-cell disease in Arabia. Comparison of two affected families, from Saudi Arabia and Jordan, showed that clinical manifestation of the disease is mirrored by the biochemical and haematological findings in affected individuals. The results are discussed in terms of the effect of co-existing thalassaemia and/or iron deficiency with Hb S. It is suggested that both genetic and acquired conditions play a role in the clinical features of the disease. The mechanisms responsible for regulation of alpha-chain synthesis by iron (haem) deficiency are discussed.
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PMID:On the nature of sickle-cell disease in the Arabian Peninsula. 53 90

This study establishes the prevalence and distribution of an MCV less than 80 fl by review of the Coulter indices of 7887 samples. Retrospectively, 146 patients are studied and the relationships between the low MCV, film microscopy, iron status, and clinical diagnosis assessed. Plasma ferritin measured radioisotopically in 100 patients is compared to serum iron and iron binding capacity values and some of the problems of assessing iron stores are discussed. The discriminant formulae devised to differentiate between the microcytosis of thalassaemia trait and that or iron deficiency are found to be of limited value when applied to the red cell indices of a hospital population.
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PMID:The low mean cell volume in routine haematology. 54 44


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