For donor ABO confirmatory typing, I always had both automated and manual methods set up on the blood bank computer system Medinfo Hematos IIG.  The automated method had a bidirectional interface between Medinfo and the instrument.   Medinfo did not need a separate middleware.  A truth table was prepared for acceptable results for automatic interpretation.  Other results had to be manually interpreted by someone with the appropriate security level.

The manual testing option is structured similarly.  Within Medinfo, it is easy to change the methodology if the system is so built.  Thus, if the analyzer for ABO typing is down, the staff can select the manual methodology.  Likewise, if one testing center goes off-line, the world can be completed at another site—no need to repeat testing already completed from the first site.  This flexibility can apply to any test in system.

The manufacturer’s recommendations for the particular reagents in use were strictly followed.  One used the range {0, 1, 2, 3, 4} as acceptable.  Another used {0, 2, 3, 4}.  Controls were included.  Most importantly, Medinfo can be configured for any set of reagent values.  Refer to the following flow diagram.

Confirmatory testing also includes D typing.  That will be considered in a future post.

6/10/20

For donor ABO typing, I always had both automated and manual methods set up on the blood bank computer system Medinfo Hematos IIG.  The automated method had a bidirectional interface between Medinfo and the instrument.   Medinfo did not need a separate middleware.  A truth table was prepared for acceptable results for automatic interpretation.  Other results had to be manually interpreted by someone with the appropriate security level.

The manufacturer’s recommendations for the particular reagents in use were strictly followed.  One used the range {0, 1, 2, 3, 4} as acceptable.  Another used {0, 2, 3, 4}.  Controls were included.  Refer to the following flow diagram.

Most importantly, Medinfo could be configured for any set of reagent values.

2/10/20

Donor immunohematology testing of components in progress is similar to patient immunohematology testing.  The tests include:

ABO forward and reverse testing

D typing by multiple monoclonal cocktails

ABO/D confirmatory testing

Antibody screening

Antibody identification

Truth tables are prepared for each test type with interpretations.  Results falling outside these ranges will require manual review and manual interpretation by a user with an appropriate level of privilege (usually senior technologist, supervisor, or transfusion physician.)

Unlike patient D typing, we want to detect partial or variant D types as D-positive since theoretically even a few epitopes of D present may be immunogenic to the patient.  In patient D typing, we can call partial D types as D-negative and use D-negative RBCs.  We don’t want to use partial D RBCs for D-negative women of child-bearing age!

This series will show several different test algorithms including both manual and automated methods.  The criteria for acceptability of the reactions are based on the manufacturers’ recommendations. 

Reflex ordering of antibody identification will occur if the antibody screen is non-negative.

28/9/20