Oropharyngeal Candidiasis (OPC) in hiv infected patients and its antifungal susceptiblity pattern by disc diffusion method

Abstract

Background: Oropharyngeal candidiasis (OPC) is an opportunistic fungal infection commonly found in Human Immunodeficiency Virus infected patients. Acquired Immunodeficiency syndrome a disease of human immune system caused by HIV, has emerged as a global crisis since its discovery in summer of 1981 in United States. The low absolute CD4+ T-lymphocyte count has traditionally been cited as the greatest risk factor for the development of OPC and current guidelines suggest increased risk once CD4+T-lymphocyte counts fall below 200 cells/mm3. Rampant, indiscriminate and long-term use of antifungals has led to the development of antifungal resistance among Candida species and hence the need of study. Methods and materials: A total of 408 Throat swab collected aseptically from patients using sterile cotton swab were seeded on Sabouraud's Dextrose Agar (SDA) and incubated at 37 °C. Any whitish, creamy, pasty colonies on SDA was suspected to be candida, gram staining and germ tube test was done for preliminary identification, further speciation was done based on colony morphology and color production on Candida Chrom Agar (HiMedia), pattern of blastoconida and chlamydospores on Cornmeal agar, and sugar fermentation test. Antifungal susceptibility testing (AST) of isolates was performed and interpreted according to Clinical and Laboratory Standards Institute (CLSI) M44-A document. Results: Among the 65 candida species isolated, Candida albicans 53 (81.5%), was the most common species followed by Candida tropicalis 3 (4.6%), Candida krusei 2 (3.1%), Candida glabrata 1 (1.5%) and 6 (9.2%) other Candida species. 26 patients had CD4+ ≤ 200 cells/mm3 and 39 patients had CD4+ ˃200 cells/mm3. There was a significant association between oral Candida carriage and CD4+ cell count ≤ 200 cells/mm3 (p < 0.001).Amphotericin B was the most potent antifungal followed by voriconazole, Itraconazole and conversely Fluconazole the most resistant. Conclusion: C. albicans was the common species isolated in our study. Candida Chrome Agar can be used as a routine media for rapid identification and candida speciation. AST needs to be done routinely to know the susceptibility pattern of isolates and initiate proper treatment of patients. Since Oral yeast colonization was associated with low CD4+ count (<200 cells/mm3). Thus oral lesion can serve as early marker for HIV infection.