Comparison of PCR to histology for the diagnosis of invasive candidiasis in a murine model.

The ability of a PCR method to diagnose invasive candidiasis in comparison to histology was determined using a murine model. One hundred and sixty mice were divided into 16 groups of 10 mice each. One group served as a negative control while 15 groups were infected with Candida albicans. Of the infected groups, 14 (A1-A7 and B1-B7) received fluconazole treatment. Surviving animals of group A1 were killed on day 3, and animals of successive groups were sacrificed every other day thereafter. Fluconazole treatment was stopped in the corresponding B group. All surviving mice were killed on day 43. One hundred and thirty-eight mice were evaluable. Yeast were seen in the kidney specimens of 77 mice; 66/77 of these, plus an additional 7 histologically-negative mice, were positive by PCR. The sensitivity and specificity of the PCR test compared with histology were 85.71% and 88.52%, respectively. In combination with blood cultures, PCR could be a useful diagnostic tool for invasive candidiasis in clinical settings.