Pattern of splenic phagocytic function in Brazilian patients with sickle cell disease.

The splenic function measured by the counts of "pitted" erythrocytes has been assessed in 87 patients with sickle cell disease (59 homozygotes for hemoglobin S (SS), 14 double heterozygotes for Hb S and beta zero thalassemia (S/beta zero thal), 4 S/beta+ thal and 10 SC patients) in Southeast Brazil. Results showed a progressive increase in pit counts according to age. The reduction pattern in the splenic function was similar for the SS, S/beta zero thal and S/beta+ thal patients, and over the age of 12 almost all patients presented counts compatible with severe splenic hypofunction. Patients with SC hemoglobinopathy presented slower development of hyposplenism and lower levels of pit counts even in advanced ages. Except for S/beta+ thal patients, the developmental pattern of hyposplenism was not different from that reported among patients in the United States and Jamaica.