Invasive fungal infections in the critically ill patient

Invasive fungal infections have become an increasingly prevalent and disturbing problem in critically ill patients. The advent of broad-spectrum antibacterial therapy and immunosuppressant therapy, among other factors such as mechanical ventilation, places the intensive care patient at significant risk for infection with pathogenic fungi. Most patients who become infected with invasive fungi, especially Candida species, have been previously colonized with the offending organism, lending to the notion that colonization precedes infection in many cases. Despite an ever-increasing array of antifungal therapy for these infections, mortality rates remain extremely high, especially when the bloodstream is the primary site of infection. In addition, a shift toward more resistant pathogens such as Candida glabrata, Candida krusei, and molds will provide clinicians with therapeutic challenges for many years. The wide variation in acquisition cost across antifungal agents adds an additional layer of complexity to clinical decision making. Newer antifungal agents, each with its own advantages and disadvantages, have become available in recent years. Placing each agent in its appropriate niche is a dilemma that has yet to be solved.