Epidemiology of nosocomial fungal infection in the 1990s.

Nosocomial fungal infections have become increasingly common. This increase has been documented globally, i.e., in Europe [1], Asia [2,3], and North and South America [4,5]. In the United States, reports to the Centers for Disease Control and Prevention’s (CDC) National Nosocomial Infections Surveillance (NNIS) System document this increase in multiple clinical sites, including bloodstream, surgical wound, lower respiratory, and urinary tract [6]. Immunocompromised patients are susceptible to, and have a high mortality rate from, fungal infection. For example, the attributable mortality rate for patients diagnosed with invasive candidiasis may be as high as 38% [7] and the crude mortality of Aspergillus spp. infection in bone marrow transplant (BMT) recipients has been reported as high as 95% [8]. The emergence of nosocomial fungal infection and its associated high mortality rate underscore the need for prevention, early clinical recognition, and sensitive and specific laboratory tests for the diagnosis of invasive fungal infection. Early clinical diagnosis of invasive fungal infection often is delayed due to non-specific clinical signs and insensitive diagnostic testing. In this article, we will review the epidemiology and diagnosis of Candida and Aspergillus spp. infections, the emergence of non-albicans Candida spp. infections, and findings from recent investigations of outbreaks caused by less common fungal pathogens.