Invasive candidiasis is caused by a type of yeast (or fungus) of the Candida species that infects your body. This infection can affect your blood, heart, brain, eyes, bones, and other parts of the body. Several types of Candida tests are available to detect and diagnose candidiasis.
What Is Candida?
Candida is a species of yeast that naturally lives on your skin and in your mouth, throat, digestive tract, and vagina. Sometimes, this yeast multiplies and causes a fungal infection known as candidiasis.
What Is Invasive Candidiasis?
Invasive candidiasis is when Candida infects your blood, brain, heart, bones, eyes, or tissues that cover your abdominal organs. If candidiasis happens in your mouth or throat, it's called oral thrush. If Candida infection spreads into your bloodstream, it's called candidemia.
Invasive candidiasis has various causes, including the following:
- In hospitalized patients, it can be caused by contamination through instruments or unclean hands of health care workers.
- Long-term or repeated use of broad-spectrum antibiotics (which target many different kinds of bacteria in the body) depletes your gut bacteria and weakens your defenses against Candida.
- Candida can enter your bloodstream if you've experienced damage or inflammation of your digestive tract lining, gastrointestinal surgery or puncture, or had a central venous catheter inserted into your arm or hand.
- A weakened immune system due to treatments like chemotherapy or corticosteroid therapy enables Candida to invade your organs through the bloodstream.
What Are the Symptoms of Invasive Candidiasis?
People who have other medical conditions are often at risk of getting invasive candidiasis. It can be difficult to tell which symptoms are caused by Candida infection.
Some common symptoms of invasive candidiasis include fever and chills. If the Candida infection spreads, symptoms may develop in the affected body parts, such as the heart, brain, eyes, or bones.
How Is Invasive Candidiasis Diagnosed?
Your doctor may order one (or more) of the following Candida tests to diagnose invasive candidiasis.
Blood culture test. The most common test for invasive candidiasis is a blood culture test. Your doctor will take your blood sample and send it to a lab to see if Candida grows from it.
Mannan antigen and anti-mannan antibody. This Candida antibody test is used to diagnose invasive candidiasis. It checks for the presence of mannan, which is a carbohydrate present in the cell wall of Candida species.
C. albicans germ tube antibody (CAGTA). This Candida antibody test detects candidiasis caused by the fungus Candida albicans. It can also detect other Candida species with lower sensitivity.
(1,3)-β-D-glucan (BDG). This test looks for the presence of BDG in the sample. Like mannan, BDG is a carbohydrate found in the cell wall of many fungus species. This test is effective in the detection of invasive fungal infections. But it can’t be used to distinguish between Candida and other species of fungi.
Polymerase chain reaction (PCR). There's no FDA-approved PCR test for Candida, but some commercial PCR tests are available. They use blood samples to detect Candida. These tests target the five most common infective Candida species: C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, and C. krusei. This allows doctors to identify the exact species causing the condition, but the results can be difficult to interpret.
T2Candida panel. The T2Candida panel is an FDA-approved test for candidemia diagnosis. It's an automated process that detects Candida in the blood. The test can also identify the five common species of Candida.
Since Candida antibody tests aren’t perfect, doctors will often perform combinations of these tests, along with DNA-based techniques, to accurately diagnose invasive candidiasis.
Once the tests are done, results are available in a few days.
What Is the Treatment for Invasive Candidiasis?
Antifungal medication is used to treat invasive candidiasis. Antifungal medications that are called echinocandins, like caspofungin, are given by intravenous injection. Those called azoles, like fluconazole, are given intravenously or orally.
If you have candidemia, your treatment will continue for two weeks after your symptoms go away and the Candida is out of your bloodstream. Invasive candidiasis in the heart, brain, or bones needs a longer time to be treated.
How Can Invasive Candidiasis Be Prevented?
Doctors usually give preventive antifungal medication like fluconazole to reduce the risk of invasive candidiasis in people who are hospitalized.
Some species of Candida like Candida auris can be multidrug-resistant, which means that they aren’t affected by most drugs. They present a global health threat as they can spread easily and cause serious infections.
Consult your doctor for more information on how to prevent invasive candidiasis.
