[S hemoglobinopathies in Argentina].

Hb S is among the most prevalent abnormal hemoglobins, its distribution being related to areas where malaria is or was once endemic. In order to establish the characteristics of sickle cell hemoglobinopathies in Argentina, all cases diagnosed in a 30-year period in the Hematology Unit of R. Gutiérrez Children's Hospital were revised. Hb S diagnoses were based minimally on a positive sickling test; in most cases, RBC and reticulocyte counts, Hb concentration, and PCV were also performed, and red cell indices were obtained according to standardized procedures. Concentrations of Hb A2 and Hb S were calculated by elution of cellulose acetate strips following electrophoresis, and Hb F was measured by alkali denaturation. Of the 925 hemoglobinopathies diagnosed, Hb S was found in 116 (12.5%): sickle-cell trait (AS) in 75, sickle-cell disease (SCD) in 8, S/beta-thalassemia (s/beta-thal) in 23, SCD or S/beta-thal in 8, S/D in 1; beta-thalassemia syndromes accounted for 785 cases (84.9%). Major findings in AS were: (a) all cases came from northern and central areas of the country, neighboring countries, and other countries (Italy and Arabic nations); (b) black ancestry was found in 15 out of 75 (20%); (c) mean hematological values were normal (Table 3), and mean Hb S level was 37.1%; (d) of 57 AS patients whose blood smears were examined, 18 showed red cell abnormalities (microcytosis and/or hypochromia); (e) AS cases with altered erythrocyte morphology had significantly lower Hb, PCV, MCH, and MCV levels when compared with those with normal morphology (Tables 5, 6).(ABSTRACT TRUNCATED AT 250 WORDS)