I asked AABB to clarify and received this response:
Please refer to AABB Blood Banks and Transfusion Services Standard 5.16 Crossmatch section (30th edition).
Standard 5.16.1 states… “The crossmatch shall use methods that demonstrate ABO incompatibility and clinically significant antibodies to red cell antigens and shall include an antiglobulin test as described in Standard 5.14.3.”
Standard 5.16.1.1 states “If no clinically significant antibodies were detected in tests performed in Standard 5.14.3 and there is no record of previous detection of such antibodies, at a minimum, detection of ABO incompatibility shall be performed.”
Standard 5.16.2 states… “If a computer system is used as a method to detect ABO incompatibility, the following requirements shall be met:….” See standards 5.16.2.1 – 5.16.2.5.
In summary, if you are doing an extended/Coombs crossmatch, you also need a method to demonstrate ABO incompatibility. This is most often done by an immediate spin crossmatch. Check your manufacturer’s instructions (Gel Cards, PeG, LISS, etc) to see if these reagents state that they also detect ABO incompatibility. Most of the time they do not, which is why an immediate crossmatch is performed along with the antiglobulin test.
An electronic crossmatch can be done in lieu of the immediate spin phase if the requirements from Standards 5.16.2.1 – 5.16.2.5 have been met. Keep in mind that an electronic crossmatch can only detect ABO incompatibilities and does not include an antiglobulin test. So if the patient needs an extended/Coombs crossmatch, how is the ABO incompatibility being demonstrated? Is the LIS validated to combine an electronic crossmatch with an extended/Coombs crossmatch (this is usually no), does the antiglobulin test detect ABO incompatibility (this is usually no), or do you need to do an immediate spin crossmatch?