In Vitro Haemolytic Activities Of Candida Albicans Strains Isolated From Hiv Positive Subjects

In this study, in vitro haemolytic activities of oral Candida albicans isolates from Human Immunodeficiency Virus infected subjects and healthy controls were studied. In our study 52 C.albicans strains isolated from Human Immunodeficiency Virus positive subjects’ and 22 C.albicans strains isolated from healthy controls’ oral rinse samples in 2003 which were stored in Ankara University School of Medicine, Medical Microbiology Department Mycology Laboratory, were investigated. Haemolytic activity was determined by using the blood agar plate assay method. Plates were incubated at 37oC in 5% CO2 for 24 and 48 h. Haemolytic index (Hz) were calculated as the ratio of the colony diameter to the beta hemolysis zone diameter. Staphylococcus aureus ATCC 12228 and Streptococcus pneumoniae ATCC 6305 were used to evaluate the alpha and beta haemolysis zones, Candida parapsilosis ATCC 22019 was used as negative control. Statistical analysis was performed with Mann-Whitney U test. The Hz values ranged from 0 ile 2.57 for the Human Immunodeficiency Virus positive group and from 0 ile 1.75 for the controls. There were no statistical difference found between the groups (p>0.05). Because our isolates are colonizing these results can be expected. When the interactions between the virulence factors in invivo environment is taken into consideration, studies investigating the other virulance factors influencing the pathogenesis of the fungus and the expression of the virulance genes are needed.