What additional investigation and testing should be done?

The first step to resolve any discrepancy is to confirm that the test was performed correctly. This involves performing a clerical check of the specimen label information, comparing it to the test tube label information and the request form information. If all is consistent, start over and repeat the entire test (in this case the ABO) using a new cell suspension. This step is often overlooked but is essential to ensuring technical accuracy before proceeding to investigate clinical reasons for the discrepancy.

First Steps in Resolving ABO Discrepancies

Remember at all times - If the discrepancy is not resolved and transfusion is required STAT, select group O RBC components and AB plasma products.

  1. Recheck suitability of specimen(s). Determine specimen suitability by checking for contamination with IV fluid, unusual color or appearance, etc.

    If there is any doubt about the identity or the quality of the specimen, collect a new specimen and repeat the ABO grouping.

  2. Check the label on the reagent vial(s) to ensure that the correct reagents were used in initial testing.
  3. Recheck reagent appearance for possible contamination by comparing it with an unopened vial of the same reagent (and lot number, if possible). Use a new reagent vial if the current vial appears contaminated.
  4. Prepare a new 3% patient cell suspension.
  5. Repeat the ABO grouping.
  6. Obtain and review the patient diagnosis and an extended transfusion/ obstetrical history. Document the number and ABO of the units transfused, if applicable. If required call other facilities the patient was recently admitted to get a thorough transfusion history.