Galactomannan (Serum/Plasma)
This test measures the presence of galactomannan, a fungal polysaccharide that can indicate infection by certain fungi, such as *Cryptococcus* or *Aspergillus*. It is often used in high-risk patients to detect fungal infections early.
["A fungal infection test that helps identify possible fungal infections in your blood or body fluids."]
Key facts at a glance
- LOINC
- 44099-0
- Short code
- Galactomannan Ag SerPl Ql IA
- Synonyms
- Galactomannan Ag SerPl Ql IA
- 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
- 86038
- 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 a weakened immune system, recent organ transplant, prolonged use of broad-spectrum antibiotics, or symptoms like fever, cough, or unexplained weight loss. It’s particularly useful for monitoring patients at higher risk of fungal infections, such as those with cancer, HIV/AIDS, or undergoing chemotherapy.
How Is the Sample Collected?
A blood sample is drawn from a vein in your arm. The blood is processed to separate serum or plasma, which is then tested for galactomannan levels. This process is quick and typically done in a lab setting.
What Does a Positive Result Mean?
A positive result suggests the presence of galactomannan, which may indicate a fungal infection. However, it does not confirm the specific type of fungus or its severity. Further testing, such as cultures or imaging, may be needed to diagnose the infection and guide treatment.
What Does a Negative Result Mean?
A negative result means no detectable galactomannan was found in your sample. However, it does not rule out a fungal infection entirely, especially if you are at high risk. Your healthcare provider may recommend additional tests or monitoring if needed.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Galactomannan testing is primarily used as a screening or confirmatory tool for fungal infections in high-risk patients. It can help detect infections early, allowing for timely treatment with antifungal medications. While not as sensitive as other diagnostic methods, it is useful in settings where fungal infections are suspected but cultures are not immediately available. Results should always be interpreted alongside clinical symptoms, patient history, and other diagnostic findings.
Short name
Galactomannan
Frequently asked questions
How long does it take to get results from this test?
Can I eat or drink before this test?
Is there any risk or discomfort associated with 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