What is Fluorescent Treponemal Antibody (FTA) test?

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From the Guidelines

FTA stands for Fluorescent Treponemal Antibody, which is a type of treponemal test used for diagnosing syphilis. This test is used in conjunction with nontreponemal tests, such as the Venereal Disease Research Laboratory (VDRL) and Rapid Plasma Reagin (RPR) tests, to confirm a diagnosis of syphilis 1. The FTA test is a definitive method for diagnosing syphilis, particularly in the early stages of the disease.

Key Points about FTA

  • FTA is a treponemal test that detects the presence of antibodies against the bacterium Treponema pallidum, which causes syphilis 1
  • The test is typically used in combination with nontreponemal tests to confirm a diagnosis of syphilis
  • FTA test results usually remain positive for life, even after treatment, in most patients 1
  • A small percentage of patients (15%-25%) who are treated during the primary stage of syphilis may revert to being serologically nonreactive after 2-3 years 1

Clinical Significance of FTA

The FTA test is an important tool for diagnosing and managing syphilis, as it can help healthcare providers confirm a diagnosis and monitor treatment response. However, it is essential to use the FTA test in conjunction with nontreponemal tests and clinical evaluation to ensure accurate diagnosis and treatment 1.

From the Research

Definition of FTA

  • The Fluorescent Treponemal Antibody-Absorption (FTA-ABS) test is a diagnostic tool used to detect antibodies against Treponema pallidum, the bacterium that causes syphilis 2, 3, 4.
  • The test is a type of treponemal test, which uses specific treponemal antigens to detect the presence of antibodies against T. pallidum 5.

Purpose of FTA

  • The FTA-ABS test is used as a confirmatory test for the diagnosis of syphilis, particularly in cases where the results of non-treponemal tests are positive or equivocal 2, 3.
  • The test is also used to detect the presence of antibodies against T. pallidum in patients with suspected syphilis, especially in the early stages of the disease 6.

Characteristics of FTA

  • The FTA-ABS test is a sensitive and specific test for the detection of antibodies against T. pallidum, with a high degree of agreement with other treponemal tests 2.
  • The test uses a fluorescent monoclonal antibody to detect the presence of T. pallidum in lesion exudates or serum samples 6.
  • The FTA-ABS test is more expensive and complicated to perform than non-treponemal tests, but it is a valuable tool for the diagnosis of syphilis, especially in cases where the results of other tests are unclear 3, 5.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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