The Susceptibility Patterns of Candida Species Isolated From Urine Samples to Posaconazole and Caspofungin

Candiduria is a rising condition among hospitalized patients and Candida albicans is the most common recovered agent. However, non-albicans Candida species (NACs) such as C. glabrata, C. krusei, C. parapsilosis, and C. tropicalis are also important. Although most Candida species especially C. albicans are sensitive to routinely used antifungals, an increasing trend in resistance has been observed among NACs. The aim of the present study was to detect the susceptibility of Candida strains recovered from candiduria in hospitalized patients against posaconazole and caspofungin. A total of 120 urine samples were taken from patients hospitalized in Intensive Care Units (ICUs) (65) and urology (55) wards. All recovered yeasts were differentiated by using CHROMagar Candida medium and routine tests for identification of Candida species. Minimal inhibitory concentrations (MICs) of all isolates towards posaconazole and caspofungin were determined using the microdilution method with serial dilutions from 8 to 0.0625 µg/mL (posaconazole) and 4 to 0.03125 µg/ mL (caspofungin). In total, 41.7% of urine samples were positive for Candida isolation, including C. albicans (46%), C. glabrata (24%), C. tropicalis (16%) and C. krusei (14%). The MIC of caspofungin for 90% of the tested isolates was lower than 2 µg/mL. Furthermore, 94% of the tested isolates were inhibited by posaconazole at lower than 2 µg/mL after 24 hours, whereas 6% of isolates had MICs of more than 4 µg/mL. This study demonstrates the importance of Candida species in urine samples from hospitalized patients in ICUs and urology wards. It showed that both tested antifungals had excellent effects on different species of Candida, however the strains from ICUs were found to be more sensitive to caspofungin than posaconazole.