×

Please Remove Adblock
Adverts are the main source of Revenue for DoveMed. Please remove adblock to help us create the best medical content found on the Internet.

Fungal Infection Blood Tests

Last updated Oct. 11, 2015

Fungal Infection Blood Tests are a series of tests to identify mycoses in blood.


What are the other Names for this Test? (Equivalent Terms)

  • Calcofluor White Stain Blood Test
  • Mycology Blood Test
  • Potassium Hydroxide Preparation Blood Test

What is Fungal Infection Blood Test? (Background Information)

  • Fungal Infection Blood Test is a common term for a variety of test methods to detect the presence of fungus in a blood sample. These methods may include smear test, antigen detection through molecular testing methods and culture, antibody detection test, and fungal culture
  • Fungi (plural for fungus) are a diverse, complex group of microscopic organisms. A small subset may cause diseases that, in healthy individuals, are usually mild. However, those with weakened immune systems may experience severe illness. Over 50,000 different species of fungi exist in nature. Of these, less than 200 species can infect humans and only 50 commonly do so
  • Fungi undergo a complex, two-phase life cycle. During their vegetative phase, fungi grow and develop. They then reproduce during their reproductive phase
  • Yeasts are fungi that are single-celled and grow filaments during their reproductive phase. Molds are multi-celled and filamentous throughout their life cycles
  • Many disease-causing fungi switch between yeast and mold forms depending on the temperature of their surroundings. At room temperature (25°C), they grow as multicellular molds. They then convert to single-celled yeasts when they enter a human host (body temperature at 37°C)
  • Fungal infections are called mycoses and they can infect different parts of the body. They fall into any of the 3 categories:
    • Superficial mycoses of the skin and nails
    • Subcutaneous mycoses beneath the skin
    • Systemic mycoses involving multiple organs and organ systems      
  • Superficial and subcutaneous mycoses are fairly common. Examples include jock itch, ringworm, and athlete’s foot, which are caused by Trichophyton species. Other examples include genital infections caused by Candida species
  • Systemic mycoses are most commonly observed in those with underdeveloped or weakened immune systems. These include individuals affected by HIV infection, undergoing cancer and immunosuppressant therapy, etc.
  • Fungal Infection Blood Tests are a series of tests to identify mycoses in blood. Different tests are performed depending on the type of mycosis
  • Tests for superficial and subcutaneous mycoses include:
    • Potassium hydroxide (KOH) prep: Microscopic observation of a sample for structures belonging to fungi
    • Calcofluor stain: Dye that stains fungal structures
    • Fungal culture: Tests for growth of a sample in media under fungi-specific conditions. This test yields slower results, but allows for susceptibility testing     
  • Tests for systemic mycoses include:
    • Susceptibility tests: Applying various antifungal medications to a fungal culture to determine the most effective treatment for an individual’s mycosis
    • Antigen tests: Identify various structures specific to fungi
    • Antibody tests: Detection of specific antibodies created by the immune system upon exposure to fungi
    • Genetic material tests: The use of PCR to detect traces of specific DNA and RNA that fungi are known to possess, but that which is absent in humans

What are the Clinical Indications for performing the Fungal Infection Blood Test?

Following are the clinical indications for performing Fungal Infection Blood Tests:

  • Fever, chills
  • Cough
  • Trouble breathing
  • Nausea
  • Severe headaches
  • Stiff muscles and neck

How is the Specimen Collected for Fungal Infection Blood Test?

Following is the specimen collection process for Fungal Infection Blood Tests:

Sample required: Blood

Process of obtaining blood sample in adults:

  • A band is wrapped around the arm, 3-4 inches above the collection site (superficial vein that lies within the elbow pit)
  • The site is cleaned with 70% alcohol in an outward spiral, away from the zone of needle insertion
  • The needle cap is removed and is held in line with the vein, pulling the skin tight
  • With a small and quick thrust, the vein is penetrated using the needle
  • The required amount of blood sample is collected by pulling the plunger of the syringe out slowly
  • The wrap band is removed, gauze is placed on the collection site, and the needle is removed
  • The blood is immediately transferred into the blood container, which has the appropriate preservative/clot activator/anti-coagulant
  • The syringe and the needle are disposed into the appropriate “sharp container” for safe and hygienic disposal

Preparation required: No special preparation is needed prior to the test.

What is the Significance of the Fungal Infection Blood Test Result?

A positive Fungal Infection Blood Test may indicate a fungal infection. The species most commonly found in blood include:

  • Candida albicans
  • Histoplasma capsulatum
  • Coccidioides immitis
  • Cryptococcus neoformans
  • Members of the order Mucorales
  • Paracoccidioides brasiliensis
  • Sporothrix schenckii

The laboratory test results are NOT to be interpreted as results of a "stand-alone" test. The test results have to be interpreted after correlating with suitable clinical findings and additional supplemental tests/information. Your healthcare providers will explain the meaning of your tests results, based on the overall clinical scenario.

Additional and Relevant Useful Information:

  • Evolutionarily, fungi are very closely related to humans. This makes fungal infections difficult to treat because the number of specific ways a drug can target a fungus, but not a human, is limited

Certain medications that you may be currently taking may influence the outcome of the test. Hence, it is important to inform your healthcare provider of the complete list of medications (including any herbal supplements) you are currently taking. This will help the healthcare provider interpret your test results more accurately and avoid unnecessary chances of a misdiagnosis.

What are some Useful Resources for Additional Information?

  • The candida albicans RNA PCR blood test identifies candida present in blood

The following article link will help you understand candida albicans RNA PCR blood test:

http://www.dovemed.com/common-procedures/procedures-laboratory/candida-albicans-rna-pcr-blood-test/ 

Please visit our Laboratory Procedures Center for more physician-approved health information:

http://www.dovemed.com/common-procedures/procedures-laboratory/ 

References and Information Sources used for the Article:

Lab Tests Online (2014, October 8). Retrieved November 27, 2014 from http://labtestsonline.org/understanding/analytes/fungal/

Madigan, M. T. (2012). Brock biology of microorganisms (13th ed.). San Francisco, CA: Benjamin Cummings.

Schnell, Z. B., Van, L. A., & Kranpitz, T. R. (2003). Davis's Comprehensive handbook of laboratory and diagnostic tests: With nursing implications. Philadelphia: F.A. Davis.

Wilson, B. A., & Salyers, A. A. (2011). Bacterial pathogenesis: A molecular approach(3rd ed.). Washington, DC: ASM Press.

Reviewed and Approved by a member of the DoveMed Editorial Board
First uploaded: Sept. 7, 2015
Last updated: Oct. 11, 2015