Chlamydia Antibody Screening Test (Serum/Plasma)
This test detects antibodies in your blood that may indicate past or current infection with *Chlamydia trachomatis*, a common sexually transmitted bacterium.
["Helps identify possible chlamydia exposure, even if symptoms aren’t present."]
Key facts at a glance
- LOINC
- 110945-3
- Short code
- CHLMCSP
- Synonyms
- Chlamydia Ab Msmt CSF
- Category
- chemistry
- Sample
- csf
- Container
- Sterile, leak-proof, screw-cap polypropylene collection tube; cryogenic vial acceptable for storage
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- Enzyme Immunoassay (EIA) or Immunofluorescence Assay (IFA) for detection of Chlamydia species antibodies
- CPT
- 86631
- SNOMED
- 4526000
- Specimen volume
- 1-2 mL of cerebrospinal fluid; minimum 0.5 mL acceptable
- Stability
- Room temperature: 2 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 200
- TAT
- 48–168 hours
- Order
- routine
Why This Test Is Done
Your healthcare provider may order this test if you have symptoms like unusual discharge, pelvic pain, or if you’ve been exposed to chlamydia. It’s also part of routine screening for sexually active individuals at higher risk.
What to Expect Before the Test
No special preparation is needed. A blood sample is drawn from a vein, usually in your arm. The test uses serum or plasma from your blood.
What the Test Results Mean
Positive results suggest you may have had chlamydia in the past or could be infected now. Negative results mean no detectable antibodies were found, but this doesn’t rule out infection if you’ve been exposed recently.
Common Causes of False Results
False negatives can occur if the test was done too soon after exposure. False positives are rare but may happen if you’ve had other infections or vaccines that trigger similar immune responses.
Reference range
Negative: No detectable Chlamydia species antibodies. Positive: Indicates presence of IgG/IgM antibodies suggesting prior exposure or active infection. Titer results reported as reciprocal of highest dilution showing reactivity.N/A
No fasting required. Lumbar puncture should be performed under sterile conditions by trained personnel. Informed consent must be obtained prior to CSF collection.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Chlamydia Antibody Screen
Frequently asked questions
Early detection is critical because untreated chlamydia can lead to serious complications like pelvic inflammatory disease, infertility, or chronic pelvic pain. Treatment with antibiotics can clear the infection and prevent long-term harm.
How long will I need to wait for results?
Can I have the test done at home?
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