Biofilm formation by Candida spp. isolated from blood culture in patients with or without hematological malignancies

Abstract

Objective. To evaluate the biofilm formation by isolates of Candida spp. obtained from blood culture in patients with or without hematological malignancies. Materials and Methods. Biofilm formation by Candida spp. was determined by the method of Pierce C. and Tumbarello M. Isolates with optical density (OD) >0.1 were considered as biofilm-forming. Results. A total of 109 isolates of Candida spp. (C. albicans [n=22], C. parapsilosis [n=22], C. tropicalis [n=22], C. krusei [n=21], C. glabrata [n=22]) obtained from patients with or without hematological malignancies (55 and 54 isolates, respectively) were studied. Biofilm formation was determined in 54% of Candida spp. isolates (n=59). Biofilm production was observed more often in non-albicans species compared to C. albicans (60% versus 32%, p=0.02). The incidence of biofilm formation was significantly higher in isolates of C. tropicalis (82%) and C. krusei (81%) compared to isolates of C. parapsilosis (50%), C. albicans (32%), and C. glabrata (27%) (p<0.05). The leading biofilm-forming species were C. tropicalis and C. krusei in the both patient cohorts. Biofilm production was more frequent in C. parapsilosis isolated from patients with hematological malignancies compared to patients without hematological malignancies (73% versus 27%, p=0.03). The lowest incidence of biofilm formation was found in C. albicans (18%) isolated from patients with hematological malignancies and C. glabrata (18%) isolated from patients without hematological malignancies. Conclusions. Biofilm formation varied among the Candida spp., with the highest incidence in C. tropicalis (82%) and C. krusei (81%). There were differences in the biofilm formation incidence among Candida spp. isolated from patients with or without hematological malignancies.

Keywords

• candidemia
• candida spp
• biofilm
• hematological malignancies