Chlamydia Antibody Test (Qualitative, Fluid-Based)
This test detects antibodies to *Chlamydia trachomatis*, a common bacterial infection that can affect the reproductive system, eyes, or throat. It helps identify past or current infection when symptoms are unclear.
["This test checks for immune response to chlamydia, aiding diagnosis when symptoms aren’t obvious."]
Key facts at a glance
- LOINC
- 31764-4
- Short code
- CHLAG
- Synonyms
- Chlamydia Ag Fld Ql
- Category
- chemistry
- Sample
- serum
- Container
- Sterile, leak-proof container
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- Enzyme Immunoassay (EIA) / Immunochromatographic Antigen Detection
- CPT
- 87320
- SNOMED
- 10828004
- Specimen volume
- 1-2 mL of body fluid
- Stability
- Refrigerated (2-8°C) for up to 24 hours; frozen (-20°C or below) for up to 30 days; room temperature for up to 2 hours
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What This Test Measures
The test measures the presence of antibodies (immunoglobulins) produced by your immune system in response to *Chlamydia trachomatis*. Antibodies indicate past exposure or an active infection, though they may not appear immediately after exposure.
How the Test Works
This is a qualitative immunoassay (likely fluorescence or chemiluminescence-based) performed on bodily fluids (e.g., blood serum/plasma). The test detects specific antibody markers against chlamydia antigens, providing a yes/no result.
When You Might Need This Test
Your healthcare provider may recommend this test if you have symptoms like abnormal vaginal/penile discharge, pain during urination, or lower abdominal pain. It’s also used in routine screening for sexually active individuals at higher risk (e.g., unprotected sex history).
What to Expect Before the Test
No special preparation is needed. You may donate blood or provide a sample of bodily fluid (e.g., serum/plasma) during a routine lab visit. If testing urine, follow your provider’s instructions for specimen collection.
Reference range
Negative (Antigen not detected)N/A
No special preparation required. Patients should abstain from sexual activity for at least 24 hours prior to specimen collection when possible. Avoid douching or vaginal medications before sample collection.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Positive results suggest past or current chlamydia infection, which can cause complications like pelvic inflammatory disease (PID), infertility, or chronic pelvic pain. Early detection and treatment with antibiotics can prevent these issues. False positives may occur with other infections or prior exposure, so confirmatory testing may be needed.
Short name
Chlamydia Antibody Screen (Qual/Fluid)
Frequently asked questions
How long does it take to get results?
Can I have this test if I’m pregnant?
What if my test is positive?
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