CPT® Code 86593

The CPT® Code 86593 refers to a quantitative syphilis test that detects non-treponemal antibodies in the blood. Syphilis is a sexually transmitted disease (STD) caused by the bacterium Treponema pallidum. The disease progresses through several stages, starting with the primary stage characterized by the appearance of a sore known as a chancre at the site of infection. Although the chancre typically resolves on its own within 3 to 6 weeks, the individual remains infected. If left untreated, syphilis can advance to the secondary stage, which may present with a variety of symptoms including a skin rash, particularly on the palms and soles, as well as fever, swollen lymph nodes, sore throat, hair loss, headaches, weight loss, muscle aches, and fatigue. These secondary symptoms may also resolve spontaneously, but the infection persists. As the disease progresses, individuals may enter a latent stage where symptoms may not manifest for a decade or two. In the late stage of syphilis, serious complications can arise, including difficulties in muscle coordination, paralysis, numbness, gradual blindness, and dementia, as the infection can severely damage internal organs such as the brain, nerves, eyes, heart, blood vessels, liver, bones, and joints. Particularly concerning is the risk of undiagnosed syphilis during pregnancy, as the infection can be transmitted to the fetus, leading to stillbirth or neonatal death shortly after birth. Infants who survive may face significant health challenges, including developmental delays or seizures. The quantitative test indicated by CPT® Code 86593 is performed following a positive qualitative screening test, such as the venereal disease research laboratory (VDRL) test, rapid plasma reagin (RPR) test, or automated reagin test (ART). These qualitative tests measure the antibody response to lipoidal antigens from T. pallidum and/or the interaction of antibodies with host tissues. Quantitative testing, which may utilize enzyme-linked immunosorbent assay (ELISA), is essential for assessing disease activity and monitoring treatment response. Both qualitative and quantitative tests can be conducted on blood samples, and in cases where central nervous system involvement is suspected, cerebrospinal fluid (CSF) may be tested.