title: Long-term follow-up testing of red cell alloantibodies.
abstract: BACKGROUND
  In previous studies, 29 to 34 percent of potentially hemolytic red cell antibodies were not detected after short-term follow-up.
  
  
  METHODS
  To examine long-term detection, records were reviewed for 44 consecutive patients who were tested more than 5 years after their potentially hemolytic red cell antibodies were first identified in this hospital.
  
  
  RESULTS
  After 5 to 10 years, 14 (39%) of 36 Rh, Kell, and Duffy system antibodies were not detected on at least one occasion. Twenty-two other such antibodies were sought again after more than 10 years; 10 (45%) were not detected. When restimulation by pregnancy was excluded, these rates were 42 and 48 percent, respectively.
  
  
  CONCLUSIONS
  Clinically significant red cell antibody formation is probably more common than previously realized, because nearly half of these antibodies are undetected after long-term follow-up.
authors.affiliation: Department of Pathology, Northwestern University Medical School, Chicago, Illinois.
authors.forename: G
authors.initials: G
authors.lastname: Ramsey
authors.forename: S J
authors.initials: SJ
authors.lastname: Smietana
mesh_terms: D001789:Blood Group Antigens / Q000276:immunology*; D004375:Duffy Blood-Group System / Q000276:immunology; D005260:Female; D006801:Humans; D007518:Isoantibodies / Q000097:blood*; D007626:Kell Blood-Group System / Q000276:immunology; D008297:Male; D012189:Retrospective Studies; D012204:Rh-Hr Blood-Group System / Q000276:immunology; D013997:Time Factors
chemical_list: D001789:Blood Group Antigens; D004375:Duffy Blood-Group System; D007518:Isoantibodies; D007626:Kell Blood-Group System; D012204:Rh-Hr Blood-Group System