Chlamydia Antibody Screening by Serology (Qualitative)
This test detects antibodies in your blood that may indicate past or current infection with *Chlamydia trachomatis*, a common sexually transmitted bacterium. It helps identify exposure but does not confirm an active infection.
["This screening helps assess past exposure to chlamydia, not current infection status."]
Key facts at a glance
- LOINC
- 7823-8
- Short code
- CHLSPAB
- Synonyms
- Chlamydia Ab Ser-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Serum separator tube (SST) or red-top clot tube
- Units
- N/A
- Ref low
- 0
- Ref high
- 1
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- Enzyme Immunoassay (EIA), Microimmunofluorescence (MIF), or Complement Fixation (CF)
- CPT
- 86631
- SNOMED
- 108919003
- Specimen volume
- 1–2 mL of serum
- Stability
- Stable for 7 days at 2–8°C; for longer storage, freeze at -20°C or below for up to 30 days
- Hemolysis max
- 100
- Lipemia max
- 100
- Icterus max
- 50
- TAT
- 24–72 hours
- Order
- routine
Why This Test Is Done
Doctors may order 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 at higher risk, including those with multiple partners or recent exposure.
What to Expect During Testing
A blood sample is taken from a vein in your arm. You may feel a small pinch, but it’s quick. Results are typically available within days to a week, depending on lab processing times.
What the Results Mean
A positive result means your blood contains antibodies suggesting past infection. A negative result means no detectable antibodies were found at this time. Antibodies don’t always appear immediately after exposure, so repeated testing may be needed.
What This Test Doesn’t Show
This test does not diagnose an active chlamydia infection. If you’re concerned about current infection, your doctor may recommend additional testing, such as a urine or cervical swab test.
Reference range
Negative: <1:64 titer; Equivocal: 1:64–1:128 titer; Positive: ≥1:256 titer (varies by laboratory and methodology)N/A
No special patient preparation required. Fasting is not necessary. Patient should be informed that serology reflects exposure history and may not differentiate active from past infection.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Chlamydia Antibody Screen (Qual)
Frequently asked questions
How long does it take to get results from this test?
Can I have this test if I’m pregnant?
Does this test require fasting?
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 15, 2026. · Read our editorial policy