Leptospira IgG Antibody Titration by Immunofluorescence (Serum)
This test measures the level of antibodies against *Leptospira*, a bacterium that can cause illness in both humans and animals. It helps detect past exposure to the bacteria, which may indicate infection from leptospirosis.
["This test helps doctors assess if you’ve been exposed to leptospira bacteria, which can cause serious illness."]
Key facts at a glance
- LOINC
- 104424-7
- Short code
- Leptospira IgM sp1 Titr Ser IA
- Synonyms
- Leptospira IgM sp1 Titr Ser IA
- Category
- coagulation
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0.8
- Ref high
- 1.2
- Critical range
- — – 5 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- ia
- CPT
- 85610
- SNOMED
- 396252006
- 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’ve had symptoms like fever, muscle aches, chills, or jaundice—common signs of leptospirosis. It’s also used in people who’ve been exposed to contaminated water, soil, or animal urine, especially in regions where leptospirosis is common.
What to Expect Before the Test
No special preparation is needed. You’ll provide a blood sample from a vein, usually in a clinic or lab. The sample is drawn into a tube and sent to a lab for testing.
How the Test Works
The test uses immunofluorescence to detect IgG antibodies specific to *Leptospira*. Antibodies are proteins your immune system makes in response to infection. Higher antibody levels suggest past exposure.
What the Results Mean
Results are reported as a titer (a measure of antibody concentration). A positive result means your body has made antibodies against leptospira, but it doesn’t confirm a current infection. Interpretation depends on clinical symptoms, exposure history, and timing since exposure.
Reference range
INR: 0.8-1.2 (warfarin: 2.0-3.0)N/A
Inform your healthcare provider if you are taking blood thinners. No special preparation required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A positive test indicates exposure to *Leptospira*, which can lead to leptospirosis—a bacterial infection spread through contaminated water or soil. While some people may not show symptoms, others can develop severe illness requiring medical attention. This test helps guide treatment decisions and monitoring.
Short name
Leptospira IgG Antibody Test (Serum)
Frequently asked questions
When might I get this test?
What does a positive result mean?
Can I take anything before this test?
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