P M Punithavathy1, K Nalina, Thangam Menon. 1. Department of Microbiology, Dr. A L Mudaliar Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani, Chennai, India.
Abstract
BACKGROUND: C.tropicalis is an important cause of nosocomial infections particularly in immunocompromised patients. Infections caused by Candida spp. are often associated with biofilm formation on implanted medical devices or on epithelial cell surfaces. Phenotypic characteristics of sessile cells in biofilms are known to be different from those of their free-living, planktonic counterparts. Biofilm forming strains often show increased resistance to antimicrobial agents. MATERIALS AND METHODS: We measured susceptibility to fluconazole of fifty C.tropicalis isolates from immunocompromised (29) and immunocompetent (21) patients by minimum inhibitory concentration (MIC) and minimum biofilm inhibitory concentration (MBIC) assays. MBIC was done using the calorimetric indicator resazurin, to measure the metabolically active cells. RESULTS: Biofilm forming cells showed increased resistance to fluconazole. CONCLUSION: The resazurin dye test was found to be a good method for determining MBIC.
BACKGROUND:C.tropicalis is an important cause of nosocomial infections particularly in immunocompromised patients. Infections caused by Candida spp. are often associated with biofilm formation on implanted medical devices or on epithelial cell surfaces. Phenotypic characteristics of sessile cells in biofilms are known to be different from those of their free-living, planktonic counterparts. Biofilm forming strains often show increased resistance to antimicrobial agents. MATERIALS AND METHODS: We measured susceptibility to fluconazole of fifty C.tropicalis isolates from immunocompromised (29) and immunocompetent (21) patients by minimum inhibitory concentration (MIC) and minimum biofilm inhibitory concentration (MBIC) assays. MBIC was done using the calorimetric indicator resazurin, to measure the metabolically active cells. RESULTS: Biofilm forming cells showed increased resistance to fluconazole. CONCLUSION: The resazurin dye test was found to be a good method for determining MBIC.