Chlamydia Antibody Test (Serum/Plasma) – Immunoassay (Screening)
This test detects antibodies in your blood that may indicate past or current infection with *Chlamydia trachomatis*, a common bacterial sexually transmitted infection.
["Helps identify possible chlamydia exposure for further evaluation or treatment."]
Key facts at a glance
- LOINC
- 109733-6
- Short code
- CHLAGCRV
- Synonyms
- Chlamydia Ag Msmt Cvx
- Category
- chemistry
- Sample
- serum
- Container
- Specific Chlamydia transport medium or viral transport medium (VTM) swab collection kit; endocervical swab in manufacturer-provided transport tube
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- female
- Age range
- 13–99 years
- Method
- Immunochromatographic assay / Enzyme Immunoassay (EIA) for direct detection of Chlamydia species antigen
- CPT
- 87320
- SNOMED
- 310861008
- Specimen volume
- 1 endocervical swab specimen collected using a Dacron, rayon, or flocked swab placed in transport medium
- Stability
- Refrigerated (2-8°C): up to 24-48 hours; Frozen (-70°C or below): up to 30 days. Room temperature stability is limited to a few hours; refer to specific kit manufacturer instructions.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–48 hours
- Order
- routine
Your healthcare provider may order this test if you have symptoms that need a clearer explanation, if a routine checkup shows something unusual, or if an ongoing condition needs close monitoring. It may also be used for screening when you have certain risk factors, or to check how well a current treatment is working for you.
Your healthcare provider may recommend this test if you have symptoms like unusual discharge, pain during urination, or if you’ve been exposed to chlamydia. It’s also part of routine screening for sexually active individuals without symptoms, especially those at higher risk (e.g., young adults, those with multiple partners).
Before your test, follow any specific instructions from your provider, which may include fasting for a set number of hours, avoiding certain medications or supplements, or drinking extra water. Tell the staff about any allergies, prescriptions, or health conditions you have, and arrive on time. If any preparation step is unclear, call the office ahead of your appointment.
No special preparation is needed. You’ll provide a blood sample (usually from a vein in your arm) during a routine office visit or lab visit. The test is quick and typically painless. If you’re pregnant, discuss any concerns with your provider before testing.
This test measures the presence or level of specific substances in your sample, such as proteins, hormones, cells, or other markers that show how your body is functioning. Your values are compared with established reference ranges, which helps your provider see whether your results fall within the expected normal range for someone like you.
This test measures antibodies in your serum or plasma that your immune system produces in response to chlamydia infection. Antibodies don’t directly confirm an active infection but suggest prior exposure or possible ongoing infection that may need further testing (e.g., culture or nucleic acid amplification).
Results are usually reported as normal, high, or low compared with a reference range. A value outside the normal range does not always mean you are ill, since factors like age, diet, medications, stress, and recent physical activity can affect the numbers. Your provider will interpret your results together with your symptoms, medical history, and any other testing you have had.
A positive result means your body has detected chlamydia antibodies, which could indicate past infection. A negative result means no detectable antibodies were found at this time. Follow-up testing (like a urine or cervical swab) may be needed to confirm active infection, especially if you have symptoms or risk factors.
Reference range
Negative: No Chlamydia sp antigen detected. Positive: Chlamydia sp antigen detected, indicating active infection.N/A
Patient should avoid douching, vaginal creams, spermicidal gels, or intercourse for at least 24 hours prior to specimen collection. Ideally, patient should not be menstruating at time of collection, but testing may still be performed. No fasting required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Chlamydia Antibody Screen
Frequently asked questions
Chlamydia is often asymptomatic but can cause serious complications if untreated, including pelvic inflammatory disease (PID), infertility, or chronic pelvic pain. Early detection and treatment with antibiotics can prevent these issues. Antibody tests are useful for screening but may not detect acute infection, so confirmatory tests are often recommended.
A positive antibody test suggests your body has encountered chlamydia at some point, but it doesn’t always mean you’re currently infected. You may need further testing (like a urine or swab test) to check for active infection. If you’re sexually active, discuss treatment options with your provider, especially if you’ve had symptoms or risk factors.
A negative antibody test means no detectable chlamydia antibodies were found in this sample. However, chlamydia can sometimes take weeks to months to trigger an immune response. If you have symptoms or were recently exposed, your provider may recommend additional testing (e.g., urine or swab) to check for active infection.
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