Ralstonia mannitolilytica infections in an oncologic day ward: description of a cluster among high-risk patients. Issue 1 (December 2017)

• Record Type: Journal Article
• Authors: Lucarelli, Claudia; Di Domenico, Enea; Toma, Luigi; Bracco, Domenico; Prignano, Grazia; Fortunati, Maria; Pelagalli, Lorella; Ensoli, Fabrizio; Pezzotti, Patrizio; García-Fernández, Aurora; Pantosti, Annalisa; Ingrosso, Loredana
• Is Part Of: Antimicrobial resistance & infection control. Volume 6:Issue 1(2017)
• Page Start: 1
• Page End: 7
• Publication Date: 2017-12
• Subjects: Ralstonia mannitolilytica -- Outbreak -- Central venous catheter -- Oncologic patients -- Carbapenem resistance; Infection -- Treatment -- Periodicals; Drug resistance -- Periodicals; Drug Resistance, Microbial -- Periodicals; 616.9041
• DOI: 10.1186/s13756-017-0178-z
• Languages: English
• ISSNs: 2047-2994

Abstract

Abstract Background Ralstonia spp, an environmental microorganism, has been occasionally associated with healthcare infections. The aim of this study was to investigate an outbreak caused byRalstonia mannitolilytica in oncology patients. Methods Case definition: Oncology outpatients attending a day ward, with positive blood and/or central venous catheter (CVC) culture forRalstonia spp from September 2013 – June 2014. We analysed medical records, procedures and environmental samples.R. mannitolilytica was identified by 16S rRNA sequencing, and typed by Pulsed Field Gel Electrophoresis (PFGE); resistance to carbapenemes was investigated by phenotypic and molecular methods. Results The patients (N = 22) had different malignancies and received different therapy; all had a CVC and 16 patients presented chills and/or fever.R. mannitolilytica was isolated from both blood and CVC (n = 12) or only blood (n = 6) or CVC tips (n = 4). The isolates had indistinguishable PFGE profile, and showed resistance to carbapenems. All the isolates were negative for carbapenemase genes while phenotypic tests suggests the presence of an AmpC β-lactamase activity, responsible for carbapenem resistance. All patients had had CVC flushed with saline to keep the venous access pervious or before receiving chemotherapy at various times before the onset of symptoms. After the first four cases occurred, the multi-dose saline bottles used for CVC flushing were replaced with single-dose vials; environmental samples were negative forR. mannitolilytica. Conclusions Although the source ofR. mannitolilytica remains unidentified, CVC flushing with contaminated saline solution seems to be the most likely origin ofR. mannitolilytica CVC colonization and subsequent infections. In order to prevent similar outbreaks we recommend removal of any CVC that is no longer necessary and the use of single-dose solutions for any parenteral treatment of oncology patients.