Nontreponemal serologic tests

Definition

Nontreponemal serologic tests are blood tests used to detect antibodies produced in response to cellular damage caused by syphilis infection. They are primarily used for screening and monitoring the treatment of syphilis.

5 Must Know Facts For Your Next Test

1. Nontreponemal tests include the Rapid Plasma Reagin (RPR) and Venereal Disease Research Laboratory (VDRL) tests.
2. These tests measure IgG and IgM antibodies against lipoidal antigens released from damaged host cells, not directly against the Treponema pallidum bacteria.
3. A positive result indicates possible syphilis infection but requires confirmation with a treponemal test due to potential false positives from other conditions like pregnancy or autoimmune diseases.
4. They are useful for monitoring treatment effectiveness because antibody titers decrease with successful therapy.
5. False-negative results can occur during early primary or late latent stages of syphilis due to low antibody levels.

Review Questions

• What are two common types of nontreponemal serologic tests?
• Why do nontreponemal tests require confirmation with a treponemal test?
• How can nontreponemal serologic tests be used to monitor the effectiveness of syphilis treatment?

Related terms

Treponemal Tests: Tests that specifically detect antibodies against Treponema pallidum, such as FTA-ABS and TP-PA.

Rapid Plasma Reagin (RPR): A type of nontreponemal test used for screening syphilis by detecting reagin antibodies.

Venereal Disease Research Laboratory (VDRL): Another nontreponemal test that detects reagin antibodies in cerebrospinal fluid or blood for diagnosing syphilis.