Candida albicans antigen in serum/plasma (immunoassay)
This test detects the presence of Candida albicans, a type of yeast that can cause infections, in your bloodstream. It helps identify systemic fungal infections when other tests or symptoms suggest it may be present.
["The Candida antigen test helps diagnose infections caused by Candida albicans in your blood or organs."]
Key facts at a glance
- LOINC
- 6337-0
- Short code
- CANDAG
- Synonyms
- C albicans Ag Ser Ql ID
- Category
- chemistry
- Sample
- serum
- Container
- Red-top serum tube or serum separator tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- immune-diffusion
- CPT
- 86403
- SNOMED
- 43991004
- Specimen volume
- 1-2 mL serum (minimum 0.5 mL)
- Stability
- Serum stable for 7 days at 2-8°C; for longer storage, freeze at -20°C or below. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 24–72 hours
- Order
- routine
What This Test Measures
The test looks for specific antigens produced by *Candida albicans*—a common yeast that can become harmful if it spreads beyond the mouth or skin into deeper tissues or the bloodstream. These antigens are released when the yeast invades body tissues, signaling an active infection.
Why It Might Be Ordered
Your healthcare provider may order this test if you have symptoms like fever, fatigue, or organ dysfunction (such as kidney or liver issues) combined with risk factors like weakened immunity (e.g., from HIV, chemotherapy, or long-term steroid use) or recent medical procedures (e.g., central venous catheters). It’s also used in patients with persistent fungal infections that don’t respond to initial treatments.
Common Uses in Clinical Practice
This test is particularly useful for monitoring patients with known or suspected invasive candidiasis (a severe infection affecting organs like the lungs, heart, or brain). It can help confirm diagnosis earlier than culture methods alone, especially in critically ill patients.
Sample Collection and Preparation
A blood sample is drawn from a vein in your arm. The blood is processed to separate serum or plasma (the liquid part of blood) for testing. The test uses an immunoassay to detect the yeast’s antigens with high sensitivity, often within 24 hours of collection.
Reference range
Negative (No Candida albicans antigen detected). Positive result indicates presence of Candida albicans antigen in serum.N/A
No fasting required. Patient should be informed about the blood draw procedure. Recent antifungal therapy may affect results.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Candida antigen test
Frequently asked questions
What does a positive result mean?
What does a negative result mean?
How often should I get 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