Diagnosing a dangerous infection by a fungal yeast that often devastates hospital patients is now faster and more efficient. The new blood test has the potential to improve patient outcomes, as the mortality rate for those with fungal yeast infections of the blood is 40 percent.
From the University of Pittsburgh, researchers introduce the T2Candida Panel, the first diagnostic test for candidemia, an infection of the bloodstream by a species of yeast called Candida.
There are 17 unique types of Candida, and candidemia is one of the four most common bloodstream infections in U.S. hospitals. A Candida infection in the blood is particularly dangerous because the yeast can spread to other parts of the body, like the eyes, liver, or brain. Signs and symptoms of such an infection include fever, chills, rash, low blood pressure, muscle aches, vision changes, headaches, and abdominal pain.
The new blood test has already been cleared by the FDA, after being tested in a clinical trial called DIRECT2. It works like this: blood is taken from a patient suspected to have candidemia and placed into a machine that uses magnetic resonance to scan the blood for the five most common Candida species. Results are available in five hours.
This is in comparison to the previous methods used to diagnose candidemia, where doctors collected a blood sample and cultured it in the lab to see if any yeast grew. However, this technique fails to detect Candida in nearly half of all infections, and it takes at least two days to receive positive results. An additional day or two is then needed to identify the specific strain of Candida.
Why is it beneficial for hospital patients (or anyone) to know if they have candidemia as soon as possible? Most importantly, an expedited diagnosis allows infected patients to receive the right medication quickly. This both treats the infection and cuts down on drug resistance because they aren’t given the wrong drug.
“For candidemia, we know that the shorter the time to administering an active antifungal medication to a patient, the higher the survival rate,” explained lead author Cornelius J. Clancy.
In the DIRECT2 trial, researchers evaluated 152 patients diagnosed with candidemia via blood culture test. The T2Candida test accurately diagnosed 89 percent of the patients, and it proved to be significantly more likely to be positive than blood cultures in patients with recent candidemia.
Future trials might include a study of whether T2Candida decreases the amount of time it takes for infected patients to receive antifungal treatment and if the new diagnostic test improves patient outcomes.
“The next steps should be evaluating it in direct clinical practice and determining if its use truly speeds up antifungal treatment, cuts unnecessary drug prescribing, results in better patient outcomes and is cost-effective, and identifies large numbers of candidemia cases that are currently not detected by blood cultures,” Clancy said.
The present study was published in the journal Clinical Infectious Diseases.
Sources: American Thoracic Society, University of Pittsburgh Schools of the Health Sciences