Abstract

Although several fungal organisms are known to infect human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS) patients, the diversity of yeast pathogens that infect individuals in South Africa is not known. In the present study sputum samples were collected from HIV positive patients who presented at the hospital with tuberculosis (TB). The yeasts organisms were isolated using potato dextrose agar and identified by germ tube test, CHROMagar and Urease based agar. The production of biofilm was tested using the microtitre plate method. The activities of amphotericin B, fluconazole and ketaconazole were tested using the standard disc diffusion method. Out of the 91 patients, 53 (58%) were females. Thirty seven patients (41%) were aged between 26 and 45 years old. The most common isolates were Cryptococcus neoformans (28%), followed byCandida parapsilopsis (19%), Candida krusei (16%), Candida albicans (15%) and Candida tropicalis (13%). The different species showed high levels of drug resistance to fluconazole (74.0%), ketaconazole (74.0%) and amphotericin B (33.7%). Biofilm production was observed in 28% of all the isolates and was not associated with drug resistance (p > 0.01). This study showed that the lungs of HIV patients with TB are often colonized by opportunistic yeasts such as Cryptococcus and Candida spp. The most common isolates included C. neoformans, C.  parapsiliosis, C. krusei and C. albicans, and amphotericin B was the most active drug against these organisms. Further studies are needed to determine the potential impact of these organisms on the emergence of multi-drug resistant (MDR) and extensively drug resistant tuberculosis (XDR TB).

Key words: Candida spp, Cryptococcus neoformans, co-infections, epidemiology, fungal infections, HIV and AIDS, opportunistic infections, tuberculosis, Venda and South Africa.