Biofilm Formation and Aspartyl Proteinase Activity and Their Association with Azole Resistance Among Causing Vulvovaginal Candidiasis, Egypt.

BACKGROUND

() is a major cause of vulvovaginal candidiasis (VVC), a condition that is commonly treated with azole agents. Biofilm formation and aspartyl proteinase production are important virulence factors that could be linked to azole resistance in impeding therapy.

AIM

To find out the association of both factors with azole resistance among isolated from VVC cases in Egyptian nonpregnant women of childbearing age.

PATIENTS AND METHODS

In a cross-sectional study, was isolated from nonpregnant females diagnosed clinically as having VVC during a 1-year study period. Susceptibility to azole agents was tested using the disc diffusion method. Biofilm formation and aspartyl proteinase production were assessed phenotypically. Additionally, two biofilm-related genes ( and ) and three proteinase genes (, and ) were screened for using polymerase chain reaction (PCR).

RESULTS

Among 204 isolates, azole resistance ratios were as follows: voriconazole (30.4%), itraconazole (17.6%), fluconazole (11.3%) and econazole (6.4%). Biofilm-producing capacity was detected in 63.2% of isolates, and 63.2% were proteinase producers. The frequencies of and were 69.6% and 74.5%, respectively, while , and were 69.2%, 88.7%, and 64.7%, respectively. Biofilm formation was significantly associated with azole resistance (P < 0.001 for each tested azole agent) as was proteinase production (P < 0.001 for fluconazole, voriconazole, and econazole resistance and P = 0.047 for itraconazole).

CONCLUSION

Among nonpregnant Egyptian women of childbearing age, azole resistance in causing VVC is significantly associated with biofilm formation and proteinase production. The development of new therapeutic agents that can target these factors is warranted.