American Board of Internal Medicine (ABIM) Certification Practice Exam

What type of testing is no longer recommended for confirming HIV immunoassay results due to the risk of false negatives?

1. HIV NAAT

2. Western blot testing

3. Rapid antibody tests

4. Standard enzyme immunoassays

The correct answer is: Western blot testing

Western blot testing was once a standard confirmatory test for HIV immunoassay results. However, it is no longer recommended due to its potential for false negative results, particularly in individuals with acute HIV infection or those with low viral loads. The inaccuracies associated with Western blot testing arise from the requirement of interpreting bands, which may vary by laboratory and lead to subjective results. Moreover, advancements in testing technology have led to the development of more reliable and efficient methods, such as HIV nucleic acid amplification tests (NAAT) for early detection and the use of rapid tests that provide results quickly and with greater accuracy. While both rapid antibody tests and standard enzyme immunoassays play crucial roles in initial screening and diagnostics, they are often followed up with methods that reduce the risk of false negatives, underscoring the shift away from Western blot testing. This evolution in HIV testing protocols emphasizes the importance of using methods that ensure high sensitivity and specificity in diagnosing HIV, thus improving overall patient care and outcomes.