Rapid identification of fungal pathogens in positive blood cultures using oligonucleotide array hybridization
Journal
Clinical Microbiology and Infection
Journal Volume
16
Journal Issue
5
Pages
493-500
Date Issued
2010
Author(s)
Abstract
Identification of fungal species in positive blood cultures using conventional methods can be time-consuming, particularly for non- albicans Candida species, non- Candida yeasts, and moulds. An oligonucleotide array system targeting the internal transcribe spacer (ITS) 1 or 2 region of the rRNA genes was used to analyse prospectively 116 fungus-positive blood cultures [BACTEC Myco/F Lytic bottles (Becton-Dickinson Microbiology Systems, Sparks, MD, USA)] from 105 patients, and the results were compared with those obtained using conventional methods. A total of 124 yeast isolates and two mould isolates were identified; these microorganisms (isolate no.) included C. albicans (50), C. tropicalis (26), C. glabrata (18), C. parapsilosis (14), Cryptococcus neoformans (9), Trichosporon asahii (2), Rhodotorula mucilaginosa (2), Penicillium marneffei (2) and three other species. Multiple species fungaemia (MSF) was detected in ten samples as opposed to six detected using conventional methods. In two discrepant samples, antifungal susceptibility testing revealed that the additionally detected isolate had higher MICs of fluconazole. An isolate reported as Rhodotorula glutinis by the Vitek Yeast Biochemical Card (bioM?rieux Vitek, Marcy l'Etoile, France) was identified as R. mucilaginosa by the array and the identification by array hybridization was confirmed by sequence analysis of the ITS region. A test sensitivity of 100% was obtained. The test specificity was 100% according to examination of 57 blood samples containing non-target fungal species or bacterium only. From the time at which growth was detected in blood cultures, the entire identification procedure could be completed within 16-24 h. ? 2009 The Authors. Journal Compilation ? 2009 European Society of Clinical Microbiology and Infectious Diseases.
SDGs
Other Subjects
amphotericin B; fluconazole; flucytosine; internal transcribed spacer 1; internal transcribed spacer 2; itraconazole; ribosome RNA; voriconazole; adult; aged; antifungal susceptibility; article; blood culture; blood sampling; Candida albicans; Candida glabrata; Candida parapsilosis; Candida tropicalis; controlled study; Cryptococcus neoformans; DNA hybridization; DNA microarray; feasibility study; female; fungal detection; fungus identification; human; in vitro study; intermethod comparison; male; minimum inhibitory concentration; mycosis; nonhuman; nucleotide sequence; Penicillium marneffei; priority journal; Rhodotorula glutinis; Rhodotorula mucilaginosa; sensitivity and specificity; sequence analysis; treatment outcome; Trichosporon asahii; Bacteria (microorganisms); Candida; Candida albicans; Candida glabrata; Candida parapsilosis; Candida tropicalis; Filobasidiella neoformans; Fungi; Penicillium marneffei; Rhodotorula glutinis; Rhodotorula mucilaginosa; Trichosporon asahii
Type
journal article