Which condition can lead to false positive results on an RPR test?

The rapid plasma reagin (RPR) test is a non-treponemal screening test for syphilis, but it can produce false positive results due to a number of conditions. One prominent cause of false positives is the presence of autoimmune disorders. In these disorders, the immune system produces antibodies that can react non-specifically with the components used in the RPR test, leading to a positive result even in the absence of syphilis. Conditions such as systemic lupus erythematosus, rheumatoid arthritis, and other autoimmune diseases have been associated with these non-specific reactions.

While other conditions can cause false positives, autoimmune disorders are particularly notable because of their mechanism of producing antibodies that cross-react with the test antigens. The other options, such as influenza, chlamydia, and uterine fibroids, do not commonly lead to the type of antibody production that would interfere with the RPR test in the same way as autoimmune diseases do. Thus, autoimmune disorders are a significant consideration in evaluating non-treponemal test results.