Anidulafungin versus fluconazole: clinical focus on IDSA and ESCMID guidelines

Invasive infections by Candida spp. play a major role in the management of the critically ill patient. Rates of positive blood cultures for Candida species have risen fivefold in the past ten years, placing this pathogen between the fourth and the sixth-leading cause of nosocomial bloodstream infections in the United States and Europe. Candida albicans is still the cause of approximately 50% of invasive candidiasis, with heterogeneous epidemiology. The echinocandin class, along with voriconazole and liposomal amphotericin B, was recommended by 2009 IDSA guidelines with AI evidence for the treatment of candidaemia, reserving the use of fluconazole in selected situations. Conversely fluconazole was downgraded to CI recommendation (marginal use), with BI evidence for voriconazole and liposomal amphotericin B, maintaining AI (strong support) for echinocandins by 2012 ESCMID guidelines for the diagnosis and management of Candida disease in non-neutropenic adult patients. Our brief analysis of randomized trials, whereby recommendations are supported, aims to discuss the possible reasons for the different consideration of fluconazole by the two above mentioned guidelines.