Date Published: August 28, 2012
Publisher: Hindawi Publishing Corporation
Author(s): Payal K. Patel, Joshua E. Erlandsen, William R. Kirkpatrick, Deborah K. Berg, Steven D. Westbrook, Christopher Louden, John E. Cornell, George R. Thompson, Ana C. Vallor, Brian L. Wickes, Nathan P. Wiederhold, Spencer W. Redding, Thomas F. Patterson.
The impact of antiretroviral therapy (ART) on opportunistic conditions in HIV patients continues to evolve. We specifically studied the changing epidemiology of oropharyngeal candidiasis (OPC) in 215 HIV/AIDS patients. Status of yeast colonization was assessed from oral rinse samples, and preliminary yeast identification was made using CHROMagar Candida and confirmed with standard microbiological techniques and/or molecular sequencing. Susceptibility to fluconazole was determined by CHROMagar Candida agar dilution screening and CLSI broth microdilution. 176 (82%) patients were colonized and 59 (27%) patients had symptomatic OPC. Candida albicans was the most prevalent species, though C. glabrata and C. dubliniensis were detected in 29% of isolates. Decreased fluconazole susceptibility occurred in 10% of isolates. Previous ART reduced the risk of OPC, while smoking increased the risk of colonization. Oral yeast colonization and symptomatic infection remain common even with advances in HIV therapy. C. albicans is the most common species, but other yeasts are prevalent and may have decreased susceptibility to fluconazole.
Candida albicans is a frequent component of oral ecology found in up to 75% of humans . In immunocompromised patients, Candida species can cause a multitude of disease manifestations ranging from mild oral disease to disseminated candidiasis. Diagnosis and treatment of disease caused by Candida species is especially important in HIV/AIDS patients who, despite the advent of antiretroviral therapy (ART), continue to suffer significant Candida associated morbidity [2, 3].
Comparable with studies done internationally, primary infections susceptible to fluconazole were largely caused by C. albicans in this study [2, 3, 10–13]. Of the non-albicans species identified in this study, C. glabrata was most frequently isolated followed by C. dubliniensis. Increased prevalence of C. dubliniensis in the last decade may be due to increased identification of the species, which can be mistaken phenotypically as C. albicans . Regarding OPC with decreased susceptibility to fluconazole, C. glabrata was the most prevalent species. C. glabrata is well known for its frequent resistance to azole antifungal agents, and it has been shown that C. glabrata often rapidly acquires fluconazole resistance with azole exposure and can upregulate drug efflux pump genes with as little as four days of in vitro fluconazole exposure .
In summary, oral yeast colonization and symptomatic infection remain common in patients with HIV/AIDS, even with ART. C. albicans is the most common species isolated in patients. Overall, clinical outcomes with fluconazole were favorable although higher doses were needed for response, particularly in patients with reduced fluconazole susceptibility. Yeasts other than C. albicans, including C. dubliniensis and C. glabrata were commonly isolated and can be significant species in the development of fluconazole resistance [10, 11, 15]. Oral yeast colonization and the possibility of resistant yeasts should be considered in patients with HIV who have risk factors for invasive infection or who have symptoms that persist after fluconazole therapy. Our results emphasize the need for continued awareness of OPC as a major cause of morbidity in HIV populations.