Remarks: RPR (Rapid Plasma Reagin) screening test is similar to the obsolete VDRL test maining that both of them measure reaginic antibodies. These antibodies are produced during infection with Treponema pallidum (the spyrochete causative of syphilis). RPR test is a useful and quick screening tool for syphilis. The ability of RPR to detect syphilis depends on the stage of the disease: In the earliest stage of syphilis (Primary syphilis) RPR is positive approximately 60% of cases. RPRT is positive in 70-90% of cases with later stages of syphilis. In the final stages of the disease, RPR test is usually positive in only 60% of cases. RPR may give a false positive results in HIV, lyme disease, mycoplasma pneumonia, malaria and systemic lupus erythematosus. In case that RPR is positive, it must be confirmed by a more specific test such as FTA-ABS.