Candida Auris Infection · What Is It, Causes, Signs, and More

Candida auris (C. auris) infection is a globally emerging fungal infection that mainly affects hospitalized individuals and has caused several outbreaks in healthcare facilities. Since its first identification in 2009, C. auris infections have been reported in dozens of countries around the world, including Colombia, India, South Africa, Spain, and the United States.    

C. auris infections are especially concerning to public health authorities because antifungal medications commonly used to treat other Candida infections are often not effective to treat C. auris. According to the Centers for Disease Control and Prevention (CDC), about 90% of C. auris isolates are resistant to at least one antifungal and around 30% of them are resistant to two antifungals; others are resistant to all three major classes of antifungal medications. 

Candida auris infection is caused by a multidrug-resistant fungus of the yeast family called Candida auris. C. auris is spread through contact with contaminated surfaces and equipment as well as from contact with an individual who is infected or colonized. Like other Candida species, C. auris can form a biofilm on the skin and other surfaces, which is a jelly-like matrix of proteins where the yeast can live and reproduce. As a result, C. auris can colonize skin without causing infection, allowing it to easily spread to others. In addition, some common healthcare disinfectants are less effective at eliminating it, allowing it to persist in the environment for weeks.  

In general, C. auris affects individuals who already have underlying medical conditions and has not been found to cause severe disease in healthy individuals. The main risk factors for acquiring C. auris infection include having a weakened immune system, long-term hospitalizations, recent major surgical procedures, recent use of broad-spectrum antibiotics, and the recent use of indwelling medical devices such as breathing tubes, feeding tubes, urinary catheters, and central venous catheters. 

Signs and symptoms of C. auris depend on the part of the body affected. C. auris can cause a wide range of hospital-related, or nosocomial, infections, including bloodstream infections, wound infections, and ear infections, among others. The most common nidus of infection is an indwelling medical device, like a central venous catheter or urinary catheter, that is colonized by the fungus. Over time, small clumps of the Candida biofilm can enter the bloodstream and cause severe invasive fungal disease. This complication is characterized by a general feeling of malaise, fever, and chills that do not improve after antibiotic treatment for a suspected bacterial infection. 

C. auris can cause infections in other locations, such as the urinary tract; heart valves, causing infective endocarditis; bones, resulting in osteomyelitis; eye, causing endophthalmitis; or joints, where it can cause septic arthritis. C. auris can also cause meningitis, specifically if present on a device like a ventricular shunt, which is used to drain excess cerebrospinal fluid (CSF). There have also been reports of skin abscesses and wound infections related to the insertion of a catheter or wound drainage device.  

Candida auris infection is generally treated by a group of antifungal medications called echinocandins such as caspofungin, micafungin, or anidulafungin. If the individual does not improve, treatment can be switched to amphotericin B, an antifungal in the polyene drug class.  Most strains of C. auris are often resistant to the third class of antifungal medications, the azoles (e.g., fluconazole, voriconazole), therefore they are not recommended in the treatment of C. auris infection.  In severe infections, especially when there is an indwelling medical device infected with a biofilm, it’s often necessary to remove the device and replace it with a new one where applicable. 

Even after treatment for invasive infections, individuals may remain colonized with C. auris for a long time or even indefinitely. Therefore, all recommended infection control measures should be followed during and after treatment for C. auris infection. The main infection prevention and control measures include hand sanitizing, washing hands with soap and water when visibly soiled, using protective gowns and gloves, cleaning and disinfecting the environment and reusable equipment, and screening contacts of newly identified cases to identify C. auris colonization.