Investigation of Discrepant ABO Blood Grouping Results from an Autoanalyzer

Area of Science:

• Transfusion Medicine
• Immunohematology
• Clinical Laboratory Science

Background:

• Limited studies evaluate failed ABO grouping cases using autoanalyzers.
• This study investigates autoanalyzer rejected cases for ABO grouping, including subgroups and discrepancies.

Purpose of the Study:

• To demonstrate the efficient use of autoanalyzers for ABO grouping.
• To analyze autoanalyzer rejected cases and identify factors influencing rejection rates.

Main Methods:

• Erytra Eflexis autoanalyzers and standard ABO RhD/reverse grouping cards were used for ABO grouping.
• Conventional tube technique (TUBE) was employed to resolve autoanalyzer-rejected or discrepant results.

Main Results:

• The overall sample rejection rate was 3.2%, with 1.9% due to discrepant results.
• Neonatal cases constituted 35.3% of rejections; ABO group A had the highest rejection rate.
• Weak reverse grouping reactivity, particularly with B red cells, and missed subgroups like A2BW and ABw were observed.

Conclusions:

• ABO group and neonatal samples significantly influence rejection rates due to weak reverse grouping.
• Confirmatory ABO grouping by TUBE and enhanced rejection criteria are necessary for detecting cis-AB and other rare subgroups.