Hydration of red cells in alpha and beta thalassemias differs. A useful approach to distinguish between these red cell phenotypes.

Differences in the pathobiologic features of alpha and beta thalassemic red cells include differing derangements in the ability of these cells to regulate their volume. To explore differences in cell hydration in these two red cell phenotypes, heterogeneity in hemoglobin concentration of individual red cells was quantitated. Red cells from 91 patients with alpha thalassemia (hemoglobin H disease) and 69 patients with beta thalassemia of the genotype beta-thal zero/Hb E were analyzed. Marked differences between these thalassemias were noted in the heterogeneity of hemoglobin concentration among individual cells. Decreased cell hemoglobin concentration and increased cell hydration were features of alpha-thalassemic blood samples, whereas both decreased and increased cell hemoglobin concentration as a result of cell hydration and dehydration, respectively, were features of beta-thalassemic blood samples. The documented differences in the hemoglobin concentration distributions should prove useful in distinguishing between the two thalassemic phenotypes.