Comparison of the efficacy of different blood medium in determining the hemolytic activity of Candida species

Abstract

Summary Hemolysins are known to be putative virulence factors contributing to pathogenicity in Candida species. In the present study, we compared the efficacy of human, rabbit and sheep blood Sabouraud-dextrose agar (SDA) medium in demonstrating the hemolysis of Candida species isolated from clinical specimens. Hemolytic activity of clinical Candida isolates was assessed with a blood plate assay. A total of 127 Candida isolates representing seven species were evaluated for their in-vitro hemolytic activities on three different mediums, including glucose 3%-enriched sheep blood SDA, glucose 3%-enriched human blood SDA and glucose 3%-enriched rabbit blood SDA. C. albicans, C. tropicalis, C. glabrata, C. kefyr and C. krusei species demonstrated beta hemolysis on all medium at 48 h postinoculation. Alpha hemolysis was detectable in C. guilliermondii species on sheep blood SDA and rabbit blood SDA, while C. parapsilosis failed to demonstrate any hemolytic activity on all medium after incubation for 48 h or longer. The value of medium in hemolytic activity was, in order superiority: sheep blood SDA > rabbit blood SDA > human blood SDA. These results suggest that sheep blood SDA is the most appropriate medium for detection of beta-hemolytic activity of Candida spp. in routine laboratory procedures.