Chlamydia Antibody, Qualitative (Serum/Plasma)
This test detects antibodies in your blood that may indicate past or current infection with *Chlamydia*, a common sexually transmitted bacterial infection.
["Helps identify if you’ve been exposed to chlamydia, even if symptoms haven’t appeared yet."]
Key facts at a glance
- LOINC
- 45104-7
- Short code
- CHLAGA
- Synonyms
- Chlamydia Ag Anal Ql IA
- Category
- chemistry
- Sample
- serum
- Container
- Sterile container or transport medium specific for Chlamydia antigen detection (e.g., viral transport medium or Chlamydia transport medium)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–120 years
- Method
- Immunoassay (Enzyme Immunoassay/EIA)
- CPT
- 87320
- SNOMED
- 121181000221106
- Specimen volume
- 1-2 mL of anal/rectal swab specimen in appropriate transport medium
- Stability
- Refrigerated (2-8°C): up to 48 hours; Frozen (-70°C or lower): up to 30 days. Specimen should be processed as soon as possible after collection.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 24–72 hours
- Order
- routine
Why This Test Is Done
Doctors may recommend this test if you have symptoms like unusual discharge, pain during urination, or pelvic pain—especially if you have multiple sexual partners or a history of STIs. It’s also used as part of routine screening for sexually active individuals under certain guidelines.
What to Expect Before the Test
No special preparation is needed. You’ll provide a blood sample, usually drawn from your arm in a clinic or lab. The test looks for antibodies (proteins your immune system makes) that may have formed in response to chlamydia infection.
What the Test Results Mean
A positive result suggests you may have had chlamydia at some point, but it doesn’t always mean you’re currently infected. A negative result means no detectable antibodies were found in this sample.
What to Do If You Get a Positive Result
If your test is positive, your healthcare provider will guide you on next steps, which may include retesting or treatment with antibiotics. Always follow their advice to clear the infection and protect others.
Reference range
Negative (Presence of Chlamydia sp antigen not detected). A positive result indicates the presence of Chlamydia species antigen in the anal specimen.N/A
No special patient preparation required. Patient should refrain from using rectal medications, enemas, or douches for at least 24 hours prior to specimen collection. Avoid antibiotic use prior to testing if clinically feasible, as it may affect results.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Chlamydia Antibody Test (Qualitative)
Frequently asked questions
Chlamydia is often asymptomatic, so early detection through screening is critical to prevent complications like pelvic inflammatory disease, infertility, or chronic pelvic pain in women, or epididymitis in men.
If I have symptoms of chlamydia, will this test show it?
Can I get this test if I’m pregnant?
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