Chlamydia IgG Antibody, Serum (Screening)
This test detects antibodies in your blood that your immune system produces in response to the Chlamydia bacterium, often years after infection. It helps screen for past exposure rather than active infection.
["This test checks for past Chlamydia infection by measuring antibodies, not current illness."]
Key facts at a glance
- LOINC
- 56911-1
- Short code
- Chlamydia IgG sp2 Ser IA-aCnc
- Synonyms
- Chlamydia IgG sp2 Ser IA-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- ia
- CPT
- 82784
- 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
Why This Test Is Done
Your healthcare provider may order this test if you have symptoms suggestive of past Chlamydia exposure, such as recurrent urinary tract infections, chronic pelvic pain, or if you’ve had symptoms in the past but no recent diagnosis. It’s also used in screening for sexually transmitted infections (STIs) in certain populations.
What to Expect Before the Test
No special preparation is needed. You’ll provide a blood sample from a vein in your arm. The process takes a few minutes, and you may feel slight discomfort, but it’s generally quick and painless.
What the Results Mean
A positive result indicates your body has produced antibodies to Chlamydia, suggesting past exposure. A negative result means no detectable antibodies were found at this time. Results alone don’t confirm current infection; they’re used alongside clinical judgment and other tests if needed.
What to Do Next
If your result is positive, discuss further testing or follow-up with your provider. If negative, you may need retesting if symptoms persist or if you’ve had recent exposure. Always follow your provider’s guidance for next steps.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
IgG Antibody to Chlamydia (Serum)
Frequently asked questions
Chlamydia is a common bacterial STI that can cause serious complications if untreated, including pelvic inflammatory disease, infertility, or chronic pain. While this test screens for past infection, it doesn’t rule out current infection. Active Chlamydia is typically diagnosed with culture or nucleic acid amplification tests.
Can I get a follow-up test to confirm current infection?
Does this test show how long ago I was infected?
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