Yi-Cheng Chang1, Hsueh-Hsia Lo2, Hsiu-Ying Hsieh3, Shan-Min Chang4. 1. Department of Internal Medicine, Fongyuan Hospital, Taichung, Taiwan. 2. Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung, Taiwan. Electronic address: sslo@ctust.edu.tw. 3. Department of Medical Laboratory Science and Biotechnology, Central Taiwan University of Science and Technology, Taichung, Taiwan. 4. Department of Laboratory Medicine, Fongyuan Hospital, Taichung, Taiwan.
Abstract
BACKGROUND: The clinical impact of Chryseobacterium indologenes infection is increasing; nevertheless, most studies had been conducted in northern Taiwan, but rarely in central Taiwan. METHODS: Using 16S rRNA gene sequencing, 34 isolates of C. indologenes were identified at the Central Region Hospital Alliance between 2007 and 2011. Vitek 2 and matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) methods were compared for the feasibility to identify this bacterium. Drug susceptibility test, biofilm formation, and pulsed-field gel electrophoresis (PFGE) were also performed. RESULTS: All isolates were collected from hospitalized patients with an average age of 70.8 ± 18.5 years. The most prevalent sample was urine (50.0%), followed by sputum (32.4%). The accuracy rate of species-level identification reached 94.1% using the Vitek 2 method and 85.3% using the MALDI-TOF MS method. All of the isolates were resistant to gentamicin, amikacin, ceftriaxone, chloramphenicol, colistin, and imipenem, but completely susceptible to minocycline. While analyzing biofilm-forming ability, 38.2% (13/34) of C. indologenes isolates displayed a positive phenotype using the Luria-Bertani (LB) medium. However, 80.0% (4/5) of invasive isolates were biofilm producers. Based on PFGE analysis, several clusters were found, and the possible intrahospital spread of this bacterium in this area could not be excluded. CONCLUSION: Both Vitek 2 and MALDI-TOF MS methods showed good ability in the determination of C. indologenes. Among the examined drugs, minocycline was the most potent one. As many as 38.2% C. indologenes isolates showed biofilm-forming ability. PFGE analyses revealed the possible intrahospital transmission of this bacterium in central Taiwan.
BACKGROUND: The clinical impact of Chryseobacterium indologenes infection is increasing; nevertheless, most studies had been conducted in northern Taiwan, but rarely in central Taiwan. METHODS: Using 16S rRNA gene sequencing, 34 isolates of C. indologenes were identified at the Central Region Hospital Alliance between 2007 and 2011. Vitek 2 and matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) methods were compared for the feasibility to identify this bacterium. Drug susceptibility test, biofilm formation, and pulsed-field gel electrophoresis (PFGE) were also performed. RESULTS: All isolates were collected from hospitalized patients with an average age of 70.8 ± 18.5 years. The most prevalent sample was urine (50.0%), followed by sputum (32.4%). The accuracy rate of species-level identification reached 94.1% using the Vitek 2 method and 85.3% using the MALDI-TOF MS method. All of the isolates were resistant to gentamicin, amikacin, ceftriaxone, chloramphenicol, colistin, and imipenem, but completely susceptible to minocycline. While analyzing biofilm-forming ability, 38.2% (13/34) of C. indologenes isolates displayed a positive phenotype using the Luria-Bertani (LB) medium. However, 80.0% (4/5) of invasive isolates were biofilm producers. Based on PFGE analysis, several clusters were found, and the possible intrahospital spread of this bacterium in this area could not be excluded. CONCLUSION: Both Vitek 2 and MALDI-TOF MS methods showed good ability in the determination of C. indologenes. Among the examined drugs, minocycline was the most potent one. As many as 38.2% C. indologenes isolates showed biofilm-forming ability. PFGE analyses revealed the possible intrahospital transmission of this bacterium in central Taiwan.
Authors: Marcelo Silva Folhas Damas; Roumayne Lopes Ferreira; Emeline Boni Campanini; Gabriela Guerrera Soares; Leslie Camelo Campos; Pedro Mendes Laprega; Andrea Soares da Costa; Caio César de Melo Freire; André Pitondo-Silva; Louise Teixeira Cerdeira; Anderson Ferreira da Cunha; Maria-Cristina da Silva Pranchevicius Journal: Front Med (Lausanne) Date: 2022-07-28