Evaluating the Sensitivity of Candida Albicans Isolates from Oral Candidiasis of AIDS Patients to Fluconazole by Microdilution Broth and Disk Diffusion Methods

Document Type : Original Article (s)

Authors

1 MSc Student, Department of Mycology, School of Medicine, Tarbiat Modares University, Tehran, Iran

2 Associate Professor, Department of Mycology, School of Medicine, Tarbiat Modares University, Tehran, Iran

3 Assistant Professor, Department of Clinical Biochemistry, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran

4 Assistant Professor, Department of Veterinary Mycology, School of Veterinary, The University of Tehran, Tehran, Iran

Abstract

Background: Candida albicans is a pathogenic yeast that causes oral, vaginal and systemic infections. Oral candidiasis is treated with antifungal agents, particularly triazoles such as fluconazole. However, the overuse of fluconazole has resulted in the emergence of azole-resistant strains of Candida. This study tried to evaluate the sensitivity to fluconazole in strains of C. albicans clinical isolates from oral candidiasis of AIDS patients by broth microdilution and disk diffusion methods.Methods: The study included 66 C. albicans isolated from oral candidiasis of AIDS patients. C. albicans ATCC10231 was used as sensitive control and C. albicans ATCC76615 as resistant control. The minimum inhibitory concentrations (MICs) of fluconazole for all isolates were determined by broth microdilution assays for yeasts according to the clinical and laboratory standards institute (CLSI) guidelines. The MICs were evaluated after 48h of incubation at 35°C. The disk diffusion test was performed according to the procedure outlined in CLSI M44-S2 document. Mueller-Hinton agar supplemented with 2% glucose and 0.5 μg/ml of methylene blue was used and the results were read after 24h incubation at 35°C.Findings: Significant differences were not observed between broth microdilution and disk diffusion methods for evaluating the sensitivity of isolates to fluconazole. Conclusion: However, while broth microdilution is a difficult, time consuming technique, disk diffusion test is a quick and simple method for determining the sensitivity of yeasts to fluconazole.

Keywords

References

  1. Sanglard D, Ischer F, Marchetti O, Entenza J, Bille J. Calcineurin A of Candida albicans: involvement in antifungal tolerance, cell morphogenesis and virulence. Mol Microbiol 2003; 48(4): 959-76.
  2. Sudbery PE. The germ tubes of Candida albicans hyphae and pseudohyphae show different patterns of septin ring localization. Mol Microbiol 2001; 41(1): 19-31.
  3. Al-Karaawi ZM, Manfredi M, Waugh AC, McCullough MJ, Jorge J, Scully C, et al. Molecular characterization of Candida spp. isolated from the oral cavities of patients from diverse clinical settings. Oral Microbiol Immunol 2002; 17(1): 44-9.
  4. Heald AE, Cox GM, Schell WA, Bartlett JA, Perfect JR. Oropharyngeal yeast flora and fluconazole resistance in HIV-infected patients receiving long-term continuous versus intermittent fluconazole therapy. AIDS 1996; 10(3): 263-8.
  5. Masia CM, Gutierrez RF, Ortiz de la Tabla Ducasse, Hernandez A, I, Martin GC, Sanchez SA, et al. Determinants for the development of oropharyngeal colonization or infection by fluconazole-resistant Candida strains in HIV-infected patients. Eur J Clin Microbiol Infect Dis 2000; 19(8): 593-601.
  6. Hospenthal DR, Murray CK, Rinaldi MG. The role of antifungal susceptibility testing in the therapy of candidiasis. Diagn Microbiol Infect Dis 2004; 48(3): 153-60.
  7. Milan EP, Burattini MN, Kallas EG, Fischmann O, Costa PR, Colombo AL. Azole resistance among oral Candida species isolates from AIDS patients under ketoconazole exposure. Diagn Microbiol Infect Dis 1998; 32(3): 211-6.
  8. White TC, Marr KA, Bowden RA. Clinical, cellular, and molecular factors that contribute to antifungal drug resistance. Clin Microbiol Rev 1998; 11(2): 382-402.
  9. Menon T, Umamaheswari K, Kumarasamy N, Solomon S, Thyagarajan SP. Efficacy of fluconazole and itraconazole in the treatment of oral candidiasis in HIV patients. Acta Trop 2001; 80(2): 151-4.
  10. Loffler J, Kelly SL, Hebart H, Schumacher U, Lass-Florl C, Einsele H. Molecular analysis of cyp51 from fluconazole-resistant Candida albicans strains. FEMS Microbiol Lett 1997; 151(2): 263-8.
  11. Wayne PA. Reference Method for Broth Dilution Antifungal Susceptibility Testing of Yeasts.Approved standard M27-A3. 3rd ed. Clinical Laboratory Standard Institute; 2008.
  12. Wayne PA. Methods for Antifungal Disk Diffusion Susceptibility Testing of Yeasts:Approved Standard M44-A. 2nd ed. Clinical Laboratory Standard Institute; 2004.
  13. Wayne PA. Zone diameter interpretive standards, corresponding minimal inhibitory concentration (MIC) interpretive breakpoints, and quality control limits for antifungal disk diffusion susceptibility testing of yeasts; Informational supplement CLSI document M44-S2. 2nd ed. Clinical and Laboratory Standards Institute; 2008.
  14. Lass-Florl C, Perkhofer S, Mayr A. In vitro susceptibility testing in fungi: a global perspective on a variety of methods. Mycoses 2010; 53(1): 1-11.
  15. Rex JH, Pfaller MA, Walsh TJ, Chaturvedi V, Espinel-Ingroff A, Ghannoum MA, et al. Antifungal susceptibility testing: practical aspects and current challenges. Clin Microbiol Rev 2001; 14(4): 643-58, table.
  16. Baccaglini L, Atkinson JC, Patton LL, Glick M, Ficarra G, Peterson DE. Management of oral lesions in HIV-positive patients. Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics 2007; 103(Suppl): S50.e1-S50.e23.
  17. Thompson GR, III, Patel PK, Kirkpatrick WR, Westbrook SD, Berg D, Erlandsen J, et al. Oropharyngeal candidiasis in the era of antiretroviral therapy. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010; 109(4): 488-95.
  18. Perea S, Lopez-Ribot JL, Kirkpatrick WR, McAtee RK, Santillan RA, Martinez M, et al. Prevalence of molecular mechanisms of resistance to azole antifungal agents in Candida albicans strains displaying high-level fluconazole resistance isolated from human immunodeficiency virus-infected patients. Antimicrob Agents Chemother 2001; 45(10): 2676-84.
  19. Ruhnke M, Eigler A, Tennagen I, Geiseler B, Engelmann E, Trautmann M. Emergence of fluconazole-resistant strains of Candida albicans in patients with recurrent oropharyngeal candidosis and human immunodeficiency virus infection. J Clin Microbiol 1994; 32(9): 2092-8.
  20. Martins MD, Lozano-Chiu M, Rex JH. Point prevalence of oropharyngeal carriage of fluconazole-resistant Candida in human immunodeficiency virus-infected patients. Clin Infect Dis 1997; 25(4): 843-6.
  21. Magaldi S, Mata S, Hartung C, Verde G, Deibis L, Roldan Y, et al. In vitro susceptibility of 137 Candida sp. isolates from HIV positive patients to several antifungal drugs. Mycopathologia 2001; 149(2): 63-8.
  22. Silva MR, Costa MR, Miranda AT, Fernandes OF, Costa CR, Paula CR. Evaluation of Etest and macrodilution broth method for antifungal susceptibility testing of Candida sp strains isolated from oral cavities of AIDS patients. Rev Inst Med Trop Sao Paulo 2002; 44(3): 121-5.
  23. Kabli SA. In vitro susceptibilities of clinical yeast isolates to antifungal drugs of polyene, pyrimidine, and azoles, and their effect in yeast adhesion and mycelial formation. Saudi Journal of Biological Sciences 2008; 15(2): 189-98.
Journal of Isfahan Medical School
Volume 29, Issue 158 - Serial Number 158
September and October 2011
Pages 1583-1592

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History

  • Receive Date: 17 March 2011
  • Revise Date: 01 November 2024
  • Accept Date: 06 April 2022

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