Concurrent sickle-cell anemia and alpha-thalassemia: effect on severity of anemia.
We studied 47 patients with sickle-cell anemia to determine the effect of alpha-thalassemia on the severity of their hemolytic anemia. We diagnosed alpha-thalassemia objectively by using alpha-globin-gene mapping to detect alpha-globin-gene deletions, studying 25 subjects with the normal four alpha-globin-genes, 18 with three, and four with two. The mean hemoglobin, hematocrit, and absolute reticulocyte levels (+/- S.D.) were 7.9 +/- 0.9 g per deciliter (4.9 +/- 0.6 mmol per liter), 22.9 +/- 2.9 per cent, and 501,000 +/- 126,000 per cubic millimeter, respectively, in the non-thalassemic group; 9.8 +/- 1.6 g per deciliter (6.1 +/- 1.0 mmol per liter), 29.0 +/- 5.0 per cent, and 361,000 +/- 51,000 per cubic millimeter in the group with three alpha-globin genes; and 9.2 +/- 1.0 g per deciliter (5.7 +/- 0.6 mmol per liter), 27.5 +/- 3.0 per cent, and 100,000 +/- 15,000 per cubic millimeter in the group with two alpha-globin genes. Deletion of alpha-globin genes was also accompanied by a decreased mean corpuscular hemoglobin concentration (MCHC) in post-reticulocyte erythrocytes and by increased hemoglobin F levels. The decreased intraerythrocytic hemoglobin S concentration and elevated hemoglobin F levels associated with alpha-thalassemia appear to diminish the degree of hemolytic anemia found in sickle-cell disease.
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000755:Anemia, Sickle Cell / Q000097:blood / Q000150:complications* / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D004906:Erythrocyte Count; D005319:Fetal Hemoglobin / Q000032:analysis; D005796:Genes; D005914:Globins / Q000235:genetics; D006400:Hematocrit; D006443:Hemoglobin A2 / Q000032:analysis; D006454:Hemoglobins / Q000032:analysis; D006461:Hemolysis; D006801:Humans; D012156:Reticulocytes; D013789:Thalassemia / Q000097:blood / Q000150:complications* / Q000235:genetics
D006454:Hemoglobins; D005914:Globins; D006443:Hemoglobin A2; D005319:Fetal Hemoglobin