If a patient sample is tested against an antisera and gentle shaking in tube testing resulted in the above agglutination pattern, how would you describe it and what are some possible etiologies for the result?

This is an example of mixed field agglutination and is indicative of circulating red cells of more than one ABO group.

Etiologies of mixed field agglutination include:

  • Recent, out of group red cell transfusions

  • Hematopoietic progenitor cell transplantation

  • Fetomaternal hemorrhage

  • Some ABO subgroups

  • Chimerism found in cases of fraternal twins

  • Mosaicism resulting from dispermy


Fung, M. K., Grossman, B. J., Hillyer, C. D., & Westhoff, C. M. (2014). Technical Manual (18th ed.). Bethesda, MD: American Association of Blood Banks.

Skill Sharpener for the Week of 2017 February 13

Skill Sharpener Solutions

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