Colorimetric법에 의한 Candida albicans의 동정

Abstract

Candidiasis and other serious candidal infections are the most frequently encountered opportunistic fungal infections and the incidence of it is now increasing. Candida albicans infections occur in a substantial number of patients with immuno- compromised, immunocompetent, and aging hosts in the population. For these reasons, the ability to rapidly isolate and identify C. albicans become ever more important. A total 404 was previously identified by API 20C(bioMerieux, France) yeast isolates were tested by the NGL, PRO test and germ tube test, and the results were compared. Organism inoculated p-nitrophenyl N-acetyl- β-D-galactosaminide(NGL) and L-proline β -naphthylamide(PRO) were incubated for 30 minutes at 35ºC and tests were observed for yellow and red color under NaOH and cinnamaldehyde reagents. All of the c. albicans were observed positive reaction for both NGL and PRO test in colorimetric method within 30 minutes. NGL, PRO test showed one false-positive and no false- negative results, whereas the germ tube test showed one false-positive and three false-negative results. The NGL, PRO test showed 100% sensitivity, 99.5% specificity, 99.5% positive predictive value and 100% negative predictive value. The germ tube test was 98.5% sensitivity and 99.5% specificity. This 30-min test is a reliable test for rapid identification of C. albicans in a clinical laboratory.