1. Presented by Eric A. Gehrie, MD and prepared by Lorraine N. Blagg, MA, MLS(ASCP)SBB

Clinical Vignette

The patient is an adult presenting for same day surgery. The patient has previously had a coronary artery bypass where he typed as an A Positive with a negative antibody screen. The patient now presents as an A Positive with a positive antibody screen on all screening cells.



Question:
What is the cause of the positive antibody screen?