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Red cell indices and alpha-thalassemia

Maria de Fátima Sonati^I; Elza Miyuki Kimura^I; Fernando Ferreira Costa^II

^IDepartamento de Patologia Clínica
^IIDepartamento de Clínica Médica, Faculdade de Ciências Médicas, UNICAMP, Caixa Postal 6111, 13081 Campinas, SP, Brasil. Send correspondence to M.F.S.

ABSTRACT

This study was performed to verify whether red cell indices can be used to identify carriers of alpha+-thalassemia (a+-thal). The hemoglobin concentration (Hb), mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were compared among Black newborns with normal and a+-thal genotypes, inferred by the presence and measurement of Hb Bart's in cord blood (5 a+-thal postulated homozygotes, 31 a+-thal heterozygotes and 252 in which Hb Bart's was not detected). In addition, the red cell indices obtained from two groups of clinically normal Black adults who had their genotype determined by DNA analysis (10 a+-thal heterozygotes and 33 with normal genotypes) were also analysed. The MCV and MCH values obtained from the a+-that homozygotes were lower than those from the heterozygotes, and both were lower than those of the control group. However, the distribution of these parameters presented considerable overlap among groups, showing that they cannot be used alone as indicators of a+-dial.

Keywords: Alpha-thalassemia.

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