In vitro Post-Antifungal Effect of Posaconazole and Its Impact on Adhesion-Related Traits and Hemolysin Production of Oral Candida dubliniensis Isolates.

OBJECTIVE: Candidal adherence to denture acrylic surfaces (DAS) and oral buccal epithelial cells (BEC), formation of candidal germ tubes (GT), candidal cell surface hydrophobicity (CSH), and hemolysin production are important pathogenic traits of Candida. The antifungal drug-induced post-antifungal effect (PAFE) also impacts the virulence of Candida. Candida dubliniensis isolates are associated with the causation of oral candidiasis which could be managed with posaconazole. Thus far there is no evidence on posaconazole-induced PAFE and its impact on adhesion-related attributes and production of hemolysin by C. dubliniensis isolates. Hence, the PAFE, adhesion to DAS and BEC, formation of GT, CSH, and hemolysin production of 20 oral C. dubliniensis isolates after brief exposure to posaconazole was ascertained.

MATERIALS AND METHODS: The PAFE, adherence to DAS and BEC, formation of GT, candidal CSH, and hemolysin production were investigated by hitherto described in vitro assays.

RESULTS: The mean PAFE (h) induced by posaconazole on C. dubliniensis isolates was 1.66. Exposure to posaconazole suppressed the ability of C. dubliniensis to adhere to DAS, BEC, formation of candidal GT, candidal CSH and to produce hemolysin by a reduction of 44, 33, 34, 36, and 15% (p < 0.005 to p < 0.001), respectively.

CONCLUSION: Exposure of C. dubliniensis isolates to posaconazole for a brief period induced an antimycotic impact by subduing its growth in addition to suppressing pathogenic adherence-associated attributes, as well as production of hemolysin.