what is rpr in blood test

The RPR (rapid plasma reagin) test is a blood test used to screen for syphilis. It measures substances called antibodies that are present in the blood of people who may have syphilis. The test is used to screen people who have symptoms of sexually transmitted infections and is routinely used to screen pregnant women for the disease. The RPR test can also be used to see how treatment for syphilis is working. After treatment with antibiotics, the levels of syphilis antibodies should fall. These levels can be monitored with another RPR test. Unchanged or rising levels can mean a persistent infection. False-positive and false-negative results are possible, and additional testing may be required to confirm a diagnosis.