The present study was carried on 85 yeast strains to monitor the predominant pathogens, of yeast infections, and the antimicrobial resistance patterns of isolated strains to fluconazole (FLU) and itraconazole (1TRA), also to compare between different methods of antimycotic sensitivity tests. Etest and semisolid agar antifungal susceptibility (SAAS) method were compared with broth microdilution method (BM). RPM! 1640 broth medium was used in determining minimal inhibitory concentration (MICs) by BM.. Etest MICs were determined with RPMI 1640 medium supplemented with I .5% agar and 2% glucose. SAAS MICs were determined with semisolid heart infusion broth containing 0.5% agar. MICs were read after incubation at 35°C. for 48h The frequencies of infections due to the various species of Candida were C.a1bicans 50(59 %) , Cg1abrata, 15(18 %) , Cparapsilosth 10(12 %), Ctropicalis 5(6 %) and other ('and/do spp 5(6%). MICs measured by Etest and SAAS are at a higher level than those measured by BM methods. C.albicans and Cparapsilosis were the most susceptible organism tested to FLU &ITRA .By BM method, lug/m1 of FLU inhibited 88% of Ca/bicans isolates, 13.3% of CgIabrata, 50% of C parapsilosis isolates, 20% qfCtropicalis isolates and 60% of other candida species. ITRA (0.25 ug/ml) inhibited 80% of C.albicans 33.3% of C.glabrata isolates. 100% of C.parapsilosis, 60% of C.tropicalis and 40% of other candida specie;. MICs of FLU &ITRA obtained by the three tests, Etest, SAAS and BM showed, no significance difference (P> 0.05) except in Cparcrpsilosis, MICs of ITRA showed highly significant difference (Pc 0.01).There was 130 statistically significant difference between the two drugs for all isolated strains regarding their sensitivity detected by each dii.kpostic test .The most common non Calbicans spp. causing infection was Cglabrata, and Cparapsilosis. FLU &ITRA were effective antifimgal agents against Candida spp. except C.glabrata was the most resistant organism. Etest is a suitable method for testing fluconazole and itraconazole susceptibility against isolates of Candida species. It can be used as an alternative method to the BM reference method for determining fluconazole and itraconazole susceptibility of yeast The SAAS method is simple and accurate. It is inexpensive and may be performed on a single isolate. It is useful as a screen test for detecting the susceptibility and resistance of yeast. |
