Ralstonia mannitolilytica infections in an oncologic day ward: description of a cluster among high-risk patients

Antimicrobial Resistance and Infection Control, Feb 2017

Background Ralstonia spp, an environmental microorganism, has been occasionally associated with healthcare infections. The aim of this study was to investigate an outbreak caused by Ralstonia mannitolilytica in oncology patients. Methods Case definition: Oncology outpatients attending a day ward, with positive blood and/or central venous catheter (CVC) culture for Ralstonia 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 for R. mannitolilytica. Conclusions Although the source of R. mannitolilytica remains unidentified, CVC flushing with contaminated saline solution seems to be the most likely origin of R. 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.

A PDF file should load here. If you do not see its contents the file may be temporarily unavailable at the journal website or you do not have a PDF plug-in installed and enabled in your browser.

Alternatively, you can download the file locally and open with any standalone PDF reader:

http://www.aricjournal.com/content/pdf/s13756-017-0178-z.pdf

Ralstonia mannitolilytica infections in an oncologic day ward: description of a cluster among high-risk patients

Lucarelli et al. Antimicrobial Resistance and Infection Control Ralstonia mannitolilytica infections in an oncologic day ward: description of a cluster among high-risk patients Claudia Lucarelli 0 1 3 Enea Gino Di Domenico 2 Luigi Toma 2 Domenico Bracco 2 Grazia Prignano 2 Maria Fortunati 2 Lorella Pelagalli 2 Fabrizio Ensoli 2 Patrizio Pezzotti 1 3 Aurora García-Fernández 1 3 Annalisa Pantosti 1 3 Loredana Ingrosso 0 1 3 0 European Program for Public Health Microbiology Training (EUPHEM), European Centre for Disease Prevention and Control , (ECDC), Stockholm , Sweden 1 Istituto Superiore di Sanità Viale Regina Elena , 299 00161 Rome , Italy 2 Istituto Nazionale Tumori Regina Elena, Istituto Dermatologico San Gallicano , Rome , Italy 3 Istituto Superiore di Sanità Viale Regina Elena , 299 00161 Rome , Italy Background: Ralstonia spp, an environmental microorganism, has been occasionally associated with healthcare infections. The aim of this study was to investigate an outbreak caused by Ralstonia mannitolilytica in oncology patients. Methods: Case definition: Oncology outpatients attending a day ward, with positive blood and/or central venous catheter (CVC) culture for Ralstonia 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 for R. mannitolilytica. Conclusions: Although the source of R. mannitolilytica remains unidentified, CVC flushing with contaminated saline solution seems to be the most likely origin of R. 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. Ralstonia mannitolilytica; Outbreak; Central venous catheter; Oncologic patients; Carbapenem resistance - Background The genus Ralstonia comprises a group of nonfermentative, Gram-negative bacteria (NFGN) found in moist environments, such as water, soil and plants [1]. Three Ralstonia species, Ralstonia pickettii, Ralstonia insidiosa and Ralstonia mannitolilytica, formerly designated Burkholderia pickettii, Burkholderia solanacearum and Pseudomonas thomasii, respectively, have been recognized as opportunistic human pathogens [1]. Their relevance has been currently re-evaluated because of their ability to survive in different types of disinfectants and to pass through 0.2-μm filters that are used to sterilize solutions [1, 2]. Ralstonia spp. is reported as a causative agent of bacteremia [3, 4], meningitis [5, 6], and sepsis [7, 8] in immunocompromised patients and of central venous catheter (CVC)-associated bacteremia in oncology patients [1–4, 9]. Several hospital outbreaks have been described that were associated with contaminated solutions, including water for injection, saline solutions, disinfectants and antiseptics [1]. Multidrug resistance in NFGN is widely reported in the literature [10, 11] and is causing increasing concern because such bacteria may have a role not only as human pathogens but also as potential reservoirs of resistance genes, particularly when they are found in hospital settings. Several studies have described resistance to fluoroquinolones, 3rd generation cephalosporin and carbapenems [1] in isolates belonging to all the three Ralstonia species. R. pickettii is the Ralstonia species most frequently reported in the literature while only a limited number of infections are attributed to R. insidiosa and R. mannitolilytica [1]. The clinical importance of these two species is probably underestimated because their biochemical patterns are similar to that of R. pickettii, making it impossible their distinction based on conventional microbiological tests only [1, 4, 12, 13]. Here we describe an outbreak caused by R. mannitolilytica in patients attending a day ward unit in an oncology hospital in Rome occurred from September 2013 – June 2014. Methods Hospital se (...truncated)


This is a preview of a remote PDF: http://www.aricjournal.com/content/pdf/s13756-017-0178-z.pdf

Claudia Lucarelli, Enea Di Domenico, Luigi Toma, Domenico Bracco, Grazia Prignano, Maria Fortunati, Lorella Pelagalli, Fabrizio Ensoli, Patrizio Pezzotti, Aurora García-Fernández, Annalisa Pantosti, Loredana Ingrosso. Ralstonia mannitolilytica infections in an oncologic day ward: description of a cluster among high-risk patients, Antimicrobial Resistance and Infection Control, 2017, pp. 20, 6, DOI: 10.1186/s13756-017-0178-z