American Board of Family Medicine (ABFM) Practice Exam

In a patient suspected of syphilis, what would be the most appropriate follow-up action if initial screening is negative?

1. Initiate immediate treatment

2. Conduct a detailed history and physical examination

3. Perform another rapid test

4. Repeat the RPR test

The correct answer is: Repeat the RPR test

When dealing with a suspected case of syphilis, a negative initial screening test, such as the Rapid Plasma Reagin (RPR) test, does not definitively rule out the infection. It is essential to understand that screening tests can yield false-negative results, particularly in the early stages of syphilis or in certain populations. Therefore, repeating the RPR test is a logical and appropriate follow-up action to confirm the initial result. The rationale for repeating the test is rooted in the understanding that if the initial screening was performed during a time when antibodies might not have fully developed—such as in recent infections—a subsequent test could yield a positive result as more antibodies are produced. This could ultimately help in making a definitive diagnosis. By choosing to repeat the RPR test, the clinician is taking a prudent approach that allows for the possibility of identifying a true infection that may have been missed initially. It also sets the stage for appropriate care and treatment should the repeat test indicate syphilis. Further investigation, such as a detailed history and physical examination, or conducting another rapid test, may also be warranted, but they do not directly address the need to reassess the initial negative screening result. Repeating the test is a straightforward method to verify or dismiss