When a specimen shows a positive initial screen but a negative confirmatory result, what is the appropriate action?

When a specimen shows a positive initial screen but a negative confirmatory result, what is the appropriate action?

• A. Ignore the discrepancy and report positive
• B. Document the outcome and consider recollection or additional testing per policy
• C. Re-run only the initial screen
• D. Release the donor's information to the regulator

Answer: (B)

When results don’t align between screening and confirmation, the situation must be handled carefully rather than acted on hastily. Screening tests are designed to be sensitive and catch potential positives, but they can yield false positives due to cross-reactivity or other matrix effects. The confirmatory test is more specific and is the step that validates the initial signal. If the initial screen is positive but the confirmatory test is negative, you have a discrepancy that needs resolution through proper procedures.

The best course is to document what happened, flag the result, and follow the lab’s policy for reconciliation. That often means recollecting the specimen or performing additional testing using a different, more specific method, or testing at a later time to resolve the discrepancy. This approach protects accuracy, the donor, and the integrity of the testing program. Releasing information to regulators or simply re-running the initial screen without addressing the conflicting result would be inappropriate, and ignoring the discrepancy would miss the opportunity to confirm the true status.