What is a fungal culture test?

A fungal culture test helps diagnose fungal infections, a health problem caused by exposure to fungi (more than one fungus). A fungus is a type of germ that lives in the air, soil, and plants, and even on our own bodies. There are more than a million different kinds of fungi. Most are harmless, but a few types of fungi can cause infections. There are two main types of fungal infections: superficial (affecting parts of the outer body) and systemic (affecting systems inside the body).

Superficial fungal infections are very common. They can affect the skin, genital area, and nails. Superficial infections include athlete's foot, vaginal yeast infections, and ringworm, which is not a worm but a fungus that can cause a circular rash on the skin. While not serious, superficial fungal infections can cause itchy, scaly rashes and other uncomfortable conditions.

Systemic fungal infections can affect your lungs, blood, and other systems in your body. These infections can be quite serious. Many of the more harmful fungi affect people with weakened immune systems. Others, such as one called sporothrix schenckii, usually affect people who work with soil and plants, though the fungi can infect people through an animal bite or scratch, often from a cat. A sporothrix infection may cause skin ulcers, lung disease, or joint problems.

Both superficial and systemic fungal infections can be diagnosed with a fungal culture test.

What is it used for?

A fungal culture test is used to find out whether you have a fungal infection. The test may help identify specific fungi, guide treatment, or determine if a fungal infection treatment is working.

Why do I need a fungal culture test?

Your health care provider may order a fungal culture test if you have symptoms of a fungal infection. The symptoms vary depending on the type of infection. Symptoms of a superficial fungal infection include:

• Red rash
• Itchy skin
• Itching or discharge in the vagina (symptoms of a vaginal yeast infection)
• White patches inside the mouth (symptoms of a mouth yeast infection, called thrush)
• Hard or brittle nails

Symptoms of a more serious, systemic fungal infection include:

• Fever
• Muscle aches
• Headaches
• Chills
• Nausea
• Fast heartbeat

What happens during a fungal culture test?

Fungi can occur in different places in the body. Fungal culture tests are performed where fungi are likely to be present. The most common types of fungal tests and their uses are listed below.

Skin or nail scraping

• Used to diagnose superficial skin or nail infections
• Test procedure:
  • Your health care provider will use a special tool to take a small sample of your skin or nails

Swab test

• Used to diagnose yeast infections in your mouth or vagina. It may also be used to diagnose certain skin infections.
• Test procedure:
  • Your health care provider will use a special swab to gather tissue or fluid from mouth, vagina, or from an open wound

Blood Test

• Used to detect the presence of fungi in the blood. Blood tests are often used to diagnose more serious fungal infections.
• Test procedure:
  • A health care professional will need a blood sample. The sample is most often taken from a vein in your arm.

Urine Test

• Used to diagnose more serious infections and sometimes to help diagnose a vaginal yeast infection
• Test procedure:
  • You will provide a sterile sample of urine in a container, as instructed by your health care provider.

Sputum Culture

Sputum is a thick mucus that is coughed up from the lungs. It is different from spit or saliva.

• Used to help diagnose fungal infections in the lungs
• Test procedure:
  • You may be asked to cough up sputum into a special container as instructed by your provider

After your sample is collected, it will be sent to a lab for analysis. You may not get your results right away. Your fungal culture needs to have enough fungi for your health care provider to make a diagnosis. While many types of fungi grow within a day or two, others can take a few weeks. The amount of time depends on the type of infection you have.

Will I need to do anything to prepare for the test?

You don't need any special preparations to test for a fungal infection.

Are there any risks to the test?

There is very little risk to having any of the different types of fungal culture tests. If a sample of your skin was taken, you may have a little bleeding or soreness at the site. If you get a blood test, you may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.