Detection of coagulase activity in pathogenic Candida species

The coagulase activities of various Candida spp were assessed using a classical tube test. A total of 125 clinical Candida isolates representing eight species (C. albicans, C. parapsilosis, C. tropicalis, C. glabrata, C. kefyr, Geotrichum candidum, C. krusei and C. guilliermondii) were incubated with rabbit, sheep or human plasma. After 24 h incubation, 29/64 (45.3%) C. albicans isolates and 23/61 (37.7%) non-albicans Candida strains were positive for coagulase in rabbit plasma, whereas 20/64 (31.2%) C. albicans and 6/61 (9.8%) non-albicans Candida isolates were positive for coagulase in sheep plasma. None of the tested Candida isolates reacted positively in human plasma. These results suggest that rabbit plasma is the most appropriate medium for detection of coagulase activity in Candida spp. Variations in coagulase production by Candida spp may be related to their pathogenicity. It is concluded that the laboratory detection of coagulase activity in clinical isolates of Candida spp may help the diagnosis of Candida-related infections.