Red blood cell alloimmunization in sickle cell disease: prevalence in 2010.
BACKGROUND
Transfusion of red blood cells (RBCs) is frequently required for care of individuals with sickle cell disease (SCD). Alloimmunization rates are high and may be reduced by matching for RBC antigens that can cause alloimmunization.


METHODS
During the PROACTIVE Feasibility Study, patients with SCD age 2 years or older admitted for pain without acute chest syndrome were enrolled for possible randomization to preventive blood transfusion or standard care. Transfusion and antibody histories were obtained at each site, and antibody screening was done, to assess transfusion burden and alloimmunization prevalence. Participating sites were surveyed regarding antigen matching practice.


RESULTS
A total of 237 patients (169 SS, 42 SC, 15 Sβ(0) -thalassemia, 11 Sβ(+) -thalassemia), 118 males and 119 females, were enrolled. Mean age was 19.3 years (range, 2.0-68.0); there were 122 children and 115 adults. A total of 75.8% had received at least a single transfusion of RBCs before the study. Thirty-four patients (14.4%) had a history of at least one alloantibody and 17 of these had more than one. When surveyed, 19 sites (83% of responders) reported antigen matching to at least include C, E, and K for transfusion of all patients with SCD.


CONCLUSIONS
Though antigen typing before transfusion of people with SCD and providing antigen-negative units is now widely employed by sickle cell centers, the alloimmunization rate remains quite high in contemporary sickle cell populations and may be due in large part to transfusions received at institutions not providing extended matching.
State University of New York-Downstate Medical Center/Kings County Hospital Center, Brooklyn, NY 11203, USA. scott.miller@downstate.edu
Scott T
ST
Miller
Hae-Young
HY
Kim
Debra L
DL
Weiner
Carrie G
CG
Wager
Dianne
D
Gallagher
Lori A
LA
Styles
Carlton D
CD
Dampier
Susan D
SD
Roseff
D056586:Acute Chest Syndrome / Q000209:etiology / Q000517:prevention & control; D000293:Adolescent; D000328:Adult; D000368:Aged; D000755:Anemia, Sickle Cell / Q000097:blood / Q000150:complications / Q000276:immunology / Q000628:therapy*; D015415:Biomarkers / Q000097:blood; D001789:Blood Group Antigens / Q000276:immunology*; D001787:Blood Group Incompatibility / Q000097:blood / Q000453:epidemiology* / Q000209:etiology / Q000517:prevention & control; D001788:Blood Grouping and Crossmatching / Q000379:methods / Q000706:statistics & numerical data*; D002648:Child; D002675:Child, Preschool; D057239:Early Termination of Clinical Trials; D017707:Erythrocyte Transfusion / Q000009:adverse effects* / Q000379:methods / Q000706:statistics & numerical data; D005240:Feasibility Studies; D005260:Female; D019538:Health Care Surveys; D006801:Humans; D007518:Isoantibodies / Q000097:blood*; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D015995:Prevalence; D014481:United States / Q000453:epidemiology; D055815:Young Adult
D015415:Biomarkers; D001789:Blood Group Antigens; D007518:Isoantibodies