Comparison of a commercial and an "In-house" rapid method for identifiction of Candida glabrata

Abstract

Candida glabrata is an opportunistic pathogen whose incidence has increased in the past years. This yeast is a cause of nosocomial infections including many superficial and systemic infections leading to morbidity and mortality especially in patients who are immunosuppressed. Candida glabrata has high Minimum Inhibitory Concentrations to azoles fluconazole and itraconazole. This means that its identification is very important and must be very rapid. Currently, Candida glabrata is identified rapidly by testing for the enzyme trehalase. The Glabrata Rapid Trehalase Test is a commercial rapid assimilation test able to identify the organism in less than 20 minutes. The main aim of the study was to compare the performance of the commercially available test and a Candida glabrata dipstick "in-house" test and to compare their performance with a reference method. The specificity and the sensitivity of the two methods were then compared where the Glabrata Rapid Trehalose Test was found to have a higher sensitivity (92.5%) and specificity (98.2%) than the sensitivity (76.6%) and specifity (97.2%) of the Glabrata "In-house" dipstick test. A percentage agreement test was also performed were the test with a highest percentage agreement was the Glabrata Rapid Trehalose. The Glabrata Rapid Trehalose test therefore remained the best test for the identification of Candida glabrata.