How is blood typed and cross-matched?
An opening statement of the importance of compatibility testing helped explain the relevance
of the process. A brief description/table of agglutinogens (membrane antigens) along with
Agglutinins (IgM Antibodies) was helpful.
Typing is the testing of individual red blood cells (donor and recipient) with anti-sera
containing anti-A, B and AB antibodies. A positive test results in agglutination. Red cells with
known antigens (A, B and O) are then tested with sera (reverse grouping). When discussion
antibody screening, a mention of Rhesus antibodies along with testing for minor antibodies
(Kell, Duff etc.) was expected.
Cross matching consists of the saline agglutination test andiIndirect Coombs testing. (This
involves incubation, washing and testing with antiglobulin serum).
Many answers confused the processes of typing, antibody screening and cross matching.