Zaineb Hamzaoui1,2, Alain Ocampo-Sosa3, Elaa Maamar1, Marta Fernandez Martinez3, Sana Ferjani1,2, Samia Hammami1,2, Sarra Harbaoui1, Nathalie Genel4, Guillaume Arlet4, Mabrouka Saidani1,5, Amine Slim1,5, Ilhem Boutiba-Ben Boubaker1,5, Luis Martinez-Martinez3,6. 1. 1 Faculty of Medicine of Tunis-LR99ES09 Research Laboratory of Antimicrobial Resistance, University of Tunis El Manar , Tunis, Tunisia . 2. 2 Faculty of Sciences of Bizerte, University of Carthage , Tunis, Tunisia . 3. 3 Service of Microbiology, University Hospital Marqués de Valdecilla-IDIVAL , Santander, Spain . 4. 4 Department of Bacteriology, Medical School, University Pierre et Marie Curie , Paris, France . 5. 5 Laboratory of Microbiology, Charles Nicolle Hospital , Tunis, Tunisia . 6. 6 Department of Molecular Biology, School of Medicine, University of Cantabria , Santander, Spain .
Abstract
OBJECTIVES: To describe clinical and molecular characteristics of an outbreak due to metallo-β-lactamases (MBLs) producing Klebsiella pneumoniae collected at Charles Nicolle Hospital of Tunis and to analyze the impact of outer membrane porin (OMP) loss on carbapenem resistance levels. METHODS: Between 2010 and 2015, 178 carbapenem-resistant Enterobacteriaceae were isolated. Screening for MBL production was performed using combined disk diffusion method, with imipenem and ethylene diamine tetraacetic acid (EDTA) as inhibitors. Resistance genes and virulence factors were identified by polymerase chain reaction (PCR) and sequencing. Genotyping was performed by pulsed-field gel electrophoresis and multilocus sequence typing. Genetic environment of carbapenemase genes was determined by PCR mapping. Conjugation assays were performed, and plasmids were assigned to incompatibility groups by PCR-based replicon typing. OMPs were profiled by sodium dodecyl sulfate-polyacrilamide gel electrophoresis, and porin genes were sequenced. RESULTS: Nineteen K. pneumoniae (10.6%) showing MBL activity were isolated from patients hospitalized on four different wards. NDM-1 was the only MBL identified, in association with blaOXA-48. All strains lacked at least one OMP, and carbapenem resistance levels were remarkably elevated in strains lacking OmpK35 and OmpK36. blaNDM-1 was located in IncFIA-type conjugative plasmid, with the same genetic context in all strains. The epidemiological diffusion of blaNDM-1 was due to two clones, one major clone belonging to sequence type (ST) 147 (n = 16) and the other clone belonging to ST307 (n = 3). CONCLUSIONS: This study describes an outbreak of NDM-1-producing K. pneumoniae strains, isolated from a Tunisian hospital, caused by two clones belonging to ST147 and ST307; and highlights the role of OMPs loss, in combination with β-lactamase expression, in conferring high carbapenem resistance.
OBJECTIVES: To describe clinical and molecular characteristics of an outbreak due to metallo-β-lactamases (MBLs) producing Klebsiella pneumoniae collected at Charles Nicolle Hospital of Tunis and to analyze the impact of outer membrane porin (OMP) loss on carbapenem resistance levels. METHODS: Between 2010 and 2015, 178 carbapenem-resistant Enterobacteriaceae were isolated. Screening for MBL production was performed using combined disk diffusion method, with imipenem and ethylene diamine tetraacetic acid (EDTA) as inhibitors. Resistance genes and virulence factors were identified by polymerase chain reaction (PCR) and sequencing. Genotyping was performed by pulsed-field gel electrophoresis and multilocus sequence typing. Genetic environment of carbapenemase genes was determined by PCR mapping. Conjugation assays were performed, and plasmids were assigned to incompatibility groups by PCR-based replicon typing. OMPs were profiled by sodium dodecyl sulfate-polyacrilamide gel electrophoresis, and porin genes were sequenced. RESULTS: Nineteen K. pneumoniae (10.6%) showing MBL activity were isolated from patients hospitalized on four different wards. NDM-1 was the only MBL identified, in association with blaOXA-48. All strains lacked at least one OMP, and carbapenem resistance levels were remarkably elevated in strains lacking OmpK35 and OmpK36. blaNDM-1 was located in IncFIA-type conjugative plasmid, with the same genetic context in all strains. The epidemiological diffusion of blaNDM-1 was due to two clones, one major clone belonging to sequence type (ST) 147 (n = 16) and the other clone belonging to ST307 (n = 3). CONCLUSIONS: This study describes an outbreak of NDM-1-producing K. pneumoniae strains, isolated from a Tunisian hospital, caused by two clones belonging to ST147 and ST307; and highlights the role of OMPs loss, in combination with β-lactamase expression, in conferring high carbapenem resistance.
Entities:
Keywords:
Klebsiella pneumoniae; New Delhi metallo-β-lactamase; carbapenem-resistant Enterobacteriaceae; carbapenemases; epidemiology; outer membrane porin
Authors: Julia Vergalli; Igor V Bodrenko; Muriel Masi; Lucile Moynié; Silvia Acosta-Gutiérrez; James H Naismith; Anne Davin-Regli; Matteo Ceccarelli; Bert van den Berg; Mathias Winterhalter; Jean-Marie Pagès Journal: Nat Rev Microbiol Date: 2019-12-02 Impact factor: 60.633
Authors: Elvira Garza-González; Rayo Morfín-Otero; Soraya Mendoza-Olazarán; Paola Bocanegra-Ibarias; Samantha Flores-Treviño; Eduardo Rodríguez-Noriega; Alfredo Ponce-de-León; Domingo Sanchez-Francia; Rafael Franco-Cendejas; Sara Arroyo-Escalante; Consuelo Velázquez-Acosta; Fabián Rojas-Larios; Luis J Quintanilla; Joyarit Y Maldonado-Anicacio; Rafael Martínez-Miranda; Heidy L Ostos-Cantú; Abraham Gomez-Choel; Juan L Jaime-Sanchez; Laura K Avilés-Benítez; José M Feliciano-Guzmán; Cynthia D Peña-López; Carlos A Couoh-May; Aaron Molina-Jaimes; Elda G Vázquez-Narvaez; Joaquín Rincón-Zuno; Raúl Rivera-Garay; Aurelio Galindo-Espinoza; Andrés Martínez-Ramirez; Javier P Mora; Reyna E Corte-Rojas; Ismelda López-Ovilla; Víctor A Monroy-Colin; Juan M Barajas-Magallón; Cecilia T Morales-De-la-Peña; Efrén Aguirre-Burciaga; Mabel Coronado-Ramírez; Alina A Rosales-García; María-de-J Ayala-Tarín; Silvia Sida-Rodríguez; Bertha A Pérez-Vega; América Navarro-Rodríguez; Gloria E Juárez-Velázquez; Carlos Miguel Cetina-Umaña; Juan P Mena-Ramírez; Jorge Canizales-Oviedo; Martha Irene Moreno-Méndez; Daniel Romero-Romero; Alejandra Arévalo-Mejía; Dulce Isabel Cobos-Canul; Gilberto Aguilar-Orozco; Jesús Silva-Sánchez; Adrián Camacho-Ortiz Journal: PLoS One Date: 2019-03-26 Impact factor: 3.240