Rapid plasma reagin (RPR)

Optimal result: 0 – 0.001 Units

By Healthmatters Editorial Team

Peer-reviewed sources

If your result is positive, due to the risk of false-positive results, your doctor will confirm the presence of syphilis with a second test, one that is specific for antibodies against the bacterium that causes syphilis, before starting your treatment. One such test is called the fluorescent treponemal antibody-absorption (FTA-ABS) test.

If your result is negative, your doctor may ask you to wait a few weeks and then return for another test if you are at a higher risk for syphilis. This is because of the RPR test’s potential for a false negative.

The rapid plasma reagin (RPR) is a test used to screen for syphilis. The RPR test measures IgM and IgG antibodies to lipoidal material released from damaged host cells as well as to lipoprotein-like material, and possibly cardiolipin released from the treponemes. The antilipoidal antibodies are antibodies that are produced not only as a consequence of syphilis and other treponemal diseases, but also in response to nontreponemal diseases of an acute and chronic nature in which tissue damage occurs.

A normal RPR blood sample shows no antibodies to syphilis. However, your doctor cannot completely rule out syphilis if they see no antibodies.

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Written by Healthmatters Editorial Team

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