A CSF sample intended for VDRL testing yields a negative RPR result because the VDRL reagent is temporarily unavailable. What is the appropriate next step?

A CSF sample intended for VDRL testing yields a negative RPR result because the VDRL reagent is temporarily unavailable. What is the appropriate next step?

• A. Report RPR as negative
• B. Freeze the CSF sample and wait for the VDRL to be available
• C. Call the physician and cancel the test
• D. Repeat RPR but inactivate CSF first

Answer: (B)

When a critical test component is temporarily unavailable, the specimen should be preserved and testing deferred rather than reporting an incomplete or potentially inaccurate result. For a CSF sample intended for VDRL, a negative RPR cannot be considered final until the VDRL test is completed. Freezing the CSF preserves the sample until the VDRL reagent is available and the test can be run properly. Reporting a negative result would be misleading because the test was not performed. Cancelling the test or calling the physician to discontinue testing is unnecessary, since the test can be completed once reagents return. Repeating the RPR after inactivating CSF is not a standard or valid approach for CSF VDRL testing, and inactivation can alter the sample and affect results.

When a critical test component is temporarily unavailable, the specimen should be preserved and testing deferred rather than reporting an incomplete or potentially inaccurate result. For a CSF sample intended for VDRL, a negative RPR cannot be considered final until the VDRL test is completed. Freezing the CSF preserves the sample until the VDRL reagent is available and the test can be run properly. Reporting a negative result would be misleading because the test was not performed. Cancelling the test or calling the physician to discontinue testing is unnecessary, since the test can be completed once reagents return. Repeating the RPR after inactivating CSF is not a standard or valid approach for CSF VDRL testing, and inactivation can alter the sample and affect results.