ABO Typing Discrepancies

As a general rule, the discrepant reaction in a typing result will be weaker than the other reactions. Thus, in the result below, the weaker reaction between the patient’s plasma and the type A typing cells can be considered the discrepancy in what otherwise looks like a type A result.

Table 1

Common reasons for ABO typing discrepancies are shown in the table below. Discrepancies are more common in reverse typing than forward typing.

Table 2

Next page: Resolving ABO discrepancies

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