Transfusion and alloimmunization in sickle cell disease. The Cooperative Study of Sickle Cell Disease

Abstract

In 1,814 patients with sickle cell disease who had been transfused, the overall rate of alloimmunization to erythrocyte antigens was 18.6%. The rate of alloimmunization in this group appears to be an explicit function of the number of transfusions received because it increases exponentially with increasing numbers of transfusions. Alloimmunization usually occurred with less than 15 transfusions, although the rate of alloimmunization continued to increase when more transfusions were given. The rate of alloimmunization was less in patients with hemoglobin SC disease and sickle-beta+ thalassemia because these patients had received fewer transfusions. Children less than 10 years old had a slightly lower rate of alloimmunization than patients in other age groups even after correction for the number of transfusions given. Women were more frequently alloimmunized than men; this was largely due to the fact that women received more transfusions than men, but in the age group 16 to 20 years the increase may have been due in part to alloimmunization owing to pregnancy. Forty-five percent of those alloimmunized made antibodies of only one specificity; 17% made four or more antibodies reacting with different antigens. Antibodies to the C and E antigens of the Rh group, the Kell antigen, and the Lewis antigens were most commonly made. These findings may be important in formulating a rational transfusion policy in sickle cell disease.

Alloimmunization in sickle cell anemia in the era of extended red cell typing

“…In our analysis, 14% of our patients who received transfusions after 2002 developed an alloantibody despite implementation of extended red blood cell typing. The most common antibodies formed were anti-C and anti-E, a finding that is similar to what has been reported in the literature for individuals with SCD [7,15]. The selection of these alloantibodies (C, E) for extended red cell typing is intended to prevent alloimmunization.…”

Developmental biology of thrombopoietin in the human fetus and neonate

“…Consequently, the risk of a patient with the Fy(a-b-) phenotype being exposed to Duffy antigen through transfusion is very high with the attendant risk of sensitization. The formation of anti-Fy a is commonly seen in these patients but antibodies directed against the Fy b antigen (including anti-Fy b and anti-Fy3) are much rarer (Rosse et al, 1990). As was the case in our patient they tend to form after multiple transfusion episodes in those already sensitized with anti-Fy a .…”

Alloimmunization among patients with transfusion‐dependent thalassemia in Taiwan

“…The relationship between the number of units transfused and alloimmunization is unknown in thalassemia. Red cell alloimmunization is reportedly more likely in patients who receive more units of blood (Fluit et al, 1990;Rosse et al, 1990;Vichinsky et al, 1990). It has been thought that transfusion at early age may offer some protection against red cell alloimmunization because of immune tolerance in young children (Michail-Merianou et al, 1987;Spanos et al, 1990;Singer et al, 2000).…”