What causes the greater variation in the ABO antibody titres of adults: individual variation or age-related variation?

Individual variation causes greater variation than do age-related differences, as shown by this study:

  • Auf der Maur C, Hodel M, Nydegger UE, Rieben R. Age dependency of ABO histo-blood group antibodies: reexamination of an old dogma. Transfusion 1993;33(11):915-8. [ Medline ]

In Case B2 an elderly group B patient had anti-A undetectable at RT immediate spin, but detectable at 4° C with 2 drops of plasma and also by using a large-volume plasma technique (4 drops) with incubation at RT. The lower levels of anti-A can likely be attributable to both old age and to individual variation.