Recent increase in life threatening Candida bloodstream infections.

Such life threatening bloodstream Candida infections or candidemia are increasing in most countries and are estimated to cause roughly 18,000 deaths annually in the USA alone( Infectious Disease Clinics of North America 2011;25:210-25.). Candidemia is now the 4^th most common form of bloodstream infection seen in the USA. Mikulska et al., state “Candidemia is … remarkably frequent in the internal medicine setting”.

In past decades, the majority of candidemia patients were severely immunocompromised patients with HIV, have certain forms of cancer like lymphoma and leukemia, or were on immunosuppressant drugs for bone or organ transplants. However, in recent years over 50% of candidemia patients have not been severely immunocompromised. Besides severe immunocompromise, other risk factors that can increase risk of candidemia include surgery, catheters, use of multiple antibiotic courses, diabetes, malnutrition, and burns

Decades ago, most Candida infections were caused by one species- Candida albicans. In recent years, other Candida species have become prominent causes of Candida infection, including Candida tropicalis, krusei, glabrata, parapsilosis, lusitaniae, guilliermondii and rugosa. Many species and strains of Candida have developed resistance to common antifungal drugs like fluconazole (Diflucan® ).

Prompt diagnosis and treatment of blood stream Candida infections is critical in reducing mortality rates. Blood culture is the standard way to detect bloodstream Candida infections. However these methods take at least 48 hours to analyze and delaying antifungal treatment that long has been show to significantly increase mortality rates. Newer blood tests which detect Candida faster include PCR (polymerase chain reaction) tests and tests which measure beta-glucans (which are produced by Candida and other fungi (molds)). Sometimes patients at higher risk for Candida are given antifungal drugs prophylactically before a specific Candida infection is diagnosed.

Traditionally, Candida infections have been treated with the azole drugs such as fluconazole (Diflucan®), itraconazole (Sporonox® ), posaconazole (Posanol®) and voriconazole (Vfend®). Unfortunately, many strains of Candida are developing resistance to these azole drugs. Intravenous amphotericin B is effective against most strains of Candida- but this drug has many adverse side effects. The newer echinocandin drugs, including anidulafungin (Eraxis®), caspofungin(Cancidas®) and micafungin (Mycamine®) are very effective against most strains of Candida and Aspergillus (but not all fungi) and have a low rate of adverse side effects.

Mikulska M, Del Bono V, Ratto S and Viscoli C. Occurrence, presentation and treatment of candidemia. Expert Reviews in Clinical Immunology 2012;8(8):755-65.