First Treponemal Test, Type
The first treponemal test is the initial blood test used to detect antibodies against Treponema pallidum, the bacterium that causes syphilis. The "type" refers to which specific treponemal method was used, such as an enzyme immunoassay, chemiluminescent immunoassay, or a rapid/particle agglutination assay.
["This result tells your care team whether the first syphilis antibody screening test was positive or negative and which testing method was used."]
Key facts at a glance
- LOINC
- 75174-3
- Short code
- FIRSTTREPONEMALTESTTYPE
- Synonyms
- —
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- cdc-cs
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What This Test Measures
Treponemal tests look for antibodies your immune system makes against Treponema pallidum, the organism that causes syphilis. The "first treponemal test" is typically the initial screening step in a testing algorithm, and its "type" indicates the specific laboratory method employed.
Why the Test Type Matters
Different treponemal methods (for example, enzyme immunoassay, chemiluminescent immunoassay, or agglutination assays) can differ slightly in sensitivity and in how results are interpreted. Knowing which method was used helps your care team understand the result and decide whether additional testing is needed.
How It Fits in the Testing Sequence
Laboratories often use a two-step approach. The first treponemal test screens for antibodies; depending on the result, a second, different test may be done to confirm or clarify the finding. The test type recorded here identifies the method used in that first step.
What Affects the Result
Results can be influenced by the stage of infection, prior treated syphilis (which can leave antibodies detectable for years), pregnancy, and other conditions that may cause false results. Your clinician interprets the result together with your history, symptoms, and any follow-up tests.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
First treponemal tests are central to modern syphilis screening, often used as the initial step in reverse-sequence algorithms. A positive result generally prompts a second, different treponemal or nontreponemal test to confirm infection and guide treatment, while a negative result usually makes active syphilis unlikely, though very early infection can occasionally be missed.
Frequently asked questions
Does a positive first treponemal test always mean I have active syphilis?
Why would my doctor order a second test after this one?
Can this test be negative even if I have syphilis?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy