Association between ERG11 Gene and Azole Resistance among Candida Isolates from Chronic Kidney Disease Patients

Abstract

Background: Chronic kidney disease patients undergoing hemodialysis are vulnerable to oropharyngeal Candida infection because of immune dysfunction, uremia-related changes, frequent healthcare exposure, and altered oral conditions. Azole antifungals remain widely used for mucosal candidiasis, but resistance is increasingly reported. The ERG11 gene encodes lanosterol 14-alpha-demethylase, the main azole target, and is therefore an important molecular marker to investigate in Candida isolates. Objective: This study evaluated the detection of ERG11 and its relationship with fluconazole and voriconazole resistance among Candida isolates obtained from chronic kidney disease patients undergoing hemodialysis. Methods: This study was designed as a hospital-based cross-sectional observational study. Oral swabs were collected from hemodialysis patients and Candida isolates were identified by conventional culture and species-level laboratory methods. Antifungal susceptibility to fluconazole and voriconazole was determined, and ERG11 was detected by PCR. Associations between ERG11 positivity and azole resistance were analyzed using categorical statistical tests, with P <= 0.05 considered significant. Results: 96 Candida-positive isolates were identified. Candida albicans was the predominant species, representing 75/96 (78.1%) isolates. Fluconazole resistance was detected in 60/96 (62.5%) isolates, while voriconazole resistance was detected in 54/96 (56.2%). ERG11 was positive in 81/96 (84.4%) isolates. Fluconazole resistance was higher among ERG11-positive isolates than ERG11-negative isolates (65.4% vs. 46.7%), but the difference was not statistically significant (P = 0.16). Voriconazole resistance was also not significantly associated with ERG11 positivity (55.6% vs. 60.0%, P = 0.74). Conclusion: ERG11 was frequently detected among Candida isolates from hemodialysis patients; however, its presence alone was not significantly associated with azole resistance. These findings suggest that ERG11 detection is useful for molecular characterization, but mutation analysis and gene expression testing are needed to clarify its functional role in resistance.