ORIGINAL ARTICLE Oral Microbiology Post-antifungal effect and adhesion to buccal epithelial cells of oral Candida dubliniensis isolates subsequent to limited exposure to amphotericin B, ketoconazole and fluconazole Arjuna N. B. Ellepola 1 , Rachel Chandy 2 & Zia U. Khan 2 1 Department of Bioclinical Sciences, Faculty of Dentistry, Health Sciences Center, Kuwait University, Jabriya, Kuwait 2 Department of Microbiology, Faculty of Medicine, Health Sciences Center, Kuwait University, Jabriya, Kuwait Keywords adhesion, amphotericin B, Candida dubliniensis, ketoconazole and fluconazole, post-antifungal effect. Correspondence Dr A. Ellepola, Department of Bioclinical Sciences, Faculty of Dentistry, Kuwait University, P.O. Box 24923, Safat 13110, Kuwait. Tel: 00965 24636714 Fax: 00965 25326049 Email: arjuna@hsc.edu.kw Received 31 October 2013; accepted 29 January 2014. doi: 10.1111/jicd.12095 Abstract Aim: The post-antifungal effect (PAFE) of Candida and its adherence to oral mucosal surfaces are important determinants of candidal pathogenicity. Can- dida dubliniensis is allied with recurrent oral candidosis. Oral candidosis can be treated with amphotericin B, ketoconazole and fluconazole. There is no infor- mation on the PAFE and its impact on adhesion to oral buccal epithelial cells (BEC) of oral C. dubliniensis isolates. Therefore, the main objective was to reconnoiter the PAFE and adhesion to BEC of 20 C. dubliniensis isolates following brief exposure to aforementioned antimycotics. Methods: After determining the minimum inhibitory concentration (MIC), C. dubliniensis isolates were exposed to sub-lethal concentrations of these drugs for 1 h. Following subsequent drug removal, the PAFE and adhesion to BEC, was determined by a turbidometric method, and an adhesion assay, respec- tively. Results: Minimum inhibitory concentration (lg/mL) to amphotericin B, ke- toconazole and fluconazole, ranged from 0.002 to 0.125, 0.002 to 0.012 and 0.016 to 0.38, respectively. Amphotericin B and ketoconazole induced mean PAFE (hours) were 2.21 and 0.6, respectively. Fluconazole failed to produce a detectable PAFE. Compared to controls, amphotericin B, ketoconazole and fluconazole suppressed the ability to adhere to BEC with a mean percentage reduction of 74.31%, 49.80% (P < 0.0001) and 29.36% (P < 0.05), respectively. Conclusions: Brief exposure to sub-lethal concentrations of aforementioned drugs would exert an antifungal effect by modifying the growth and adhesion of C. dubliniensis isolates. Introduction Oral candidosis is considered the most common human fungal infection. It could manifest as pseudomembranous and erythematous variants, Candida-induced denture sto- matitis, linear gingival erythema associated with human immunodeficiency virus (HIV) infection and median rhomboid glossitis and angular stomatitis, possibly of multi-factorial origin. 1 For instance, over 90% of the individuals infected with HIV develop oral candidosis during some stage in the disease, which is by far the most common oral manifestation in these patients. 2 Candida dubliniensis is currently documented as an opportunistic pathogen allied with recurrent oral candidiasis in AIDS patients. It has also been isolated from the oral cavity of diabetic patients, from the sputum of cystic fibrosis patients as well as from blood, 3–5 suggesting dissemina- tion to other sites as well. C. dubliniensis is closely related 186 ª 2014 Wiley Publishing Asia Pty Ltd Journal of Investigative and Clinical Dentistry (2015), 6, 186–192