Should pre-transfusion screening RBC panels contain Wr(a+) cells?

Area of Science:

• Transfusion Medicine
• Immunology
• Hematology

Background:

• Commercial red blood cell (RBC) screening sets for irregular antibodies sometimes include Wr(a+) cells.
• Anti-Wr(a) is a common naturally occurring antibody, but the risk of transfusion incompatibility is low.

Purpose of the Study:

• To evaluate the utility of using RBC sets containing Wr(a+) cells for irregular antibody screening in pre-transfusion testing.
• To assess the impact of Wr(a+) cells in screening tests on routine laboratory work.

Main Methods:

• Studied the incidence of Wr(a) antibodies in 787 transfusion-requiring patients and 151 blood donors.
• Analyzed the types of antibodies (IgM, IgG, or both) found in positive sera.

Main Results:

• Identified irregular antibodies in 64 sera, with 58 specific for Wr(a).
• Wr(a) antibodies were found in 5.8% of patients and 7.9% of donors.
• Antibody types included IgM (16), IgM+IgG (13), and IgG (27).

Conclusions:

• The inclusion of Wr(a+) cells in pre-transfusion screening is not justified as Anti-Wr(a) is typically detected during cross-matching.
• Using Wr(a+) cells increases costs and delays unit release without significant benefit.
• The use of Wr(a+) RBC-containing sets is questionable, especially in regions without pre-transfusion cross-matching.