DNA analysis in the study of fungal infections in the immunocompromised host

Fungal infections, most of which are caused by the Candida species, are an increasing problem in the immunocompromised host. The clinical manifestations of Candida infections include disseminated candidiasis, oral and esophageal infections, focal hepatic infections, peritoneal urinary tract infections, and wound infections. DNA methods, which include pulse field electrophoresis and restriction enzyme analysis of genomic DNA, have been used to increase understanding of the epidemiology of these infections. These techniques have shown that most Candida infections are endogenous or acquired from one's own flora. Recent outbreaks have provided evidence for exogenous acquisition of some isolates. Better methods for differentiation of colonization versus infection and identifying infection in the absence of positive cultures are under investigation.