The Use of a DNA Probe for Epidemiological Studies of Candidiasis in Immunocompromised Hosts

Reproducible typing procedures to differentiate isolates of Candida albicans are limited. C. albicans isolates were obtained from immunocompromised patients by using DNA restriction enzyme fragment analysis and hybridization with both a radiolabeled mitochondrial DNA probe and a nonradioactive (biotinylated) DNA probe. There were 110 pathogenic and nonpathogenic C. albicans isolates from 63 immunocompromised patients. EcoRI restriction fragment analysis with the biotinylated probe revealed different "fingerprint" patterns for 60 of 63 patients. Analysis of 57 isolates from 20 patients showed no intrapatient variation regardless of the isolation site. DNA probe "fingerprint" patterns were analyzed for eight patients on serially recovered (range, 2-18 mo) C. albicans isolates. The unique patient profiles persisted over time. The application of this biotinylated C. albicans DNA probe provides a more sensitive means than simple gel restriction fragment analysis to define the epidemiology of C. albicans infection. The use of this biotin-labeled nonradioactive probe has potential application in clinical evaluations of outbreaks of nosocomial candidiasis.