Influência da aloimunização na evolução clínica de pacientes falcêmicos – um estudo coorte

Abstract

Introduction - Sickle cell anemia is characterized by chronic hemolytic anemia, the main treatment being red blood cell transfusions. The frequent transfusions to which sickle patients are submitted cause several complications, the most common being alloimmunization. This study aims to analyze the influence of erythrocyte alloimmunization on the clinical and laboratory evolution of patients with sickle cell disease. Method - This is a historical cohort study, with some variables evaluated transversally. Replication of medical records, blood typing, antibody testing by direct and indirect Coombs test and extended erythrocyte phenotyping of patients with sickle cell disease (SS, SC, SD and Sbeta thalassemia genotype) assisted at the University Hospital of the Federal University of Sergipe. Results - Of the 374 patients, 18.78% were alloimmunized, with 16 alloantibodies found, being the most frequent: NIs, E, Jka, Fya, C and Kell. Alloimmunization was associated with a higher mean age (p = 0.03) and neonatal screening was protective for alloimmunization (p = 0.028). The presence of autoantibodies (p = 0.000006) and mean MCV were higher in alloimmunized patients (p = 0.026). The number of hospitalizations per year was higher in alloimmunized patients (p = 0.029) and the number of transfusions was determinant in the presence or absence of alloimmunization (p = 0.0000). Conclusion - Alloimmunization was directly related to positive direct Coombs, higher mean hospitalizations per year, higher number of transfusions and higher mean value of MCV. Neonatal screening was protective for alloimmunization.