Coccidioides antibody serologic test (serum/plasma)
This blood test detects antibodies to *Coccidioides* fungi, which can cause infections called coccidioidomycosis (valley fever). It helps diagnose or rule out exposure to this fungus.
["This test checks for immune response to a fungal infection that may require medical evaluation."]
Key facts at a glance
- LOINC
- 43224-5
- Short code
- Coccidioides Ab Ser CF-aCnc
- Synonyms
- Coccidioides Ab Ser CF-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
- comp-fix
- 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 Is This Test Done?
Your healthcare provider may order this test if you have symptoms like fever, cough, chest pain, or fatigue—especially if you live in or traveled to an area with high risk for *Coccidioides* exposure (e.g., parts of the southwestern U.S., Central/South America). It may also be used to monitor treatment or assess exposure in high-risk individuals (e.g., immunocompromised patients).
What Does a Positive Result Mean?
A positive result suggests your immune system has detected *Coccidioides* antibodies, indicating past or current infection. However, antibodies can remain detectable for years, even after symptoms resolve. This does not always mean active disease is present—further testing or clinical correlation may be needed to determine severity or need for treatment.
What Does a Negative Result Mean?
A negative result means your blood did not show detectable antibodies to *Coccidioides* at the time of testing. This could mean you have never been exposed or that exposure occurred recently (antibodies may take weeks to develop). It does not rule out possible infection if symptoms persist.
How Is This Test Performed?
A blood sample is drawn from a vein in your arm. The serum or plasma is then tested for antibodies using an immunoassay method to detect the presence of these immune markers.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Coccidioides antibody screening/confirmation
Frequently asked questions
This test is primarily used for screening or confirming exposure to *Coccidioides* fungi, which can cause mild to severe respiratory or systemic infections. Early detection may guide treatment decisions, especially for high-risk patients. However, symptoms alone should not rely solely on this test for diagnosis—your healthcare provider will consider symptoms, medical history, and other factors.
Antibodies may remain detectable for months or years after infection resolves. This does not always indicate ongoing disease, but follow-up testing may be advised if symptoms recur or if you have an immunocompromised condition.
No special preparation is needed, but inform your provider about any medications, allergies, or recent illnesses that could affect results.
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