Antifungal susceptibility of oral isolates of Candida species from chronic kidney disease patients on chronic dialysis

Abstract

Chronic renal disease patients under chronic dialysis (CRDD) have a multifactorial immunological deterioration with an increased risk of Candida infections. Incidence of Candida infections is increasing. Choice of suitable antifungal agents is limited due to the resistance of some species to several antifungals. Aim of the present study was to identify the distribution and antifungal susceptibility patterns of oral isolated Candida species from infected and colonized patients, as well as to investigate the risk factors for oral infection in patients on dialysis. Cross-sectional study, approved by the institutional bioethics committees was performed in CRDD patients. Demographic, clinic data, and oral mucosa samples were obtained. Infection diagnosis was established clinically and confirmed with exfoliative cytology, each sample was plated on CHROMagar Candida and incubated at 36°C for 2 days. Yeast species were identified by carbohydrate assimilation ID 32C AUX system and the apiweb database. For the antifungal susceptibility test, the M44 A-3 method (CLSI) using fluconazole (FCZ), miconazole (MCZ), nystatin (NYS), and voriconazole (VCZ). Study included 119 participants, the main cause of CRD was nephropathy due to DM2 (58%), and three-fourths of the patients were under hemodialysis. Candida prevalence was 56.3% of 67 colonized or infected patients, 88 isolates were obtained. Principal identified species were C. albicans (51.1%), C. glabrata (25%), and C. tropicalis (14.8%). C. glabrata showed a reduced response to FCZ in 50% of isolates and C. albicans had a reduced response in 16% of the isolates. Antifungal agent with the least efficacious response or with the lowest susceptibility in the isolates of these patients was MCZ, followed by VCZ and FCZ, whereas NYS induced the best antifungal response.

Keywords: Antifungals susceptibility; Candida species; Chronic renal disease; Oral candidiasis.