title: Occurrence of OXA-48 and NDM-1 carbapenemase-producing Klebsiella pneumoniae in a Moroccan university hospital in Casablanca, Morocco.
abstract: The purpose of this investigation was to determine the prevalence and the characteristics of carbapenemase-producing Klebsiellapneumoniae isolates recovered from various clinical specimens in the university hospital of Casablanca, in Morocco. We conducted a prospective study on a total of 166 K. pneumoniae isolates collected from June to August 2011. The strains suspected to carry carbapenemase showed reduced susceptibility to imipenem or ertapenem. The PCR and a sequencing strategy were used to identify carbapenemases, expended spectrum β-lactamases (ESBL), plasmid-mediated AmpC β-lactamases, plasmid mediated quinolone resistance and aminoglycoside resistance determinants. The clonal relationships between isolates were analyzed by pulsed field gel electrophoresis (PFGE). Among the 166 K. pneumoniae isolates studied, 11 (6%) were carbapenemases producers, 9 of which harbored blaOXA-48 and 2 were positive for blaNDM-1. All carbapenemase-producing K. pneumoniae were also ESBL producers and the blaCTX-M-15 was the most frequent ESBL gene detected (n=9), blaCTX-M-28 and blaSHV-28 were also encountered in one isolate each. The K.pneumoniae isolates carried also non-ESBL genes blaTEM-1 (n=9), blaSHV-1 (n=8) and blaOXA-1 (n=3). Five isolates harbored qnr genes, qnrS1 (n=3) and qnrB1 (n=2) variants. Six isolates were positive for aac(6')-Ib-cr gene and two for aac(3)-II gene. The class 1 integron was detected in five isolates. PFGE has revealed the presence of a clonal dissemination in our hospital. The results of conjugation experiments indicated that blaOXA-48+blaCTX-M-15, blaOXA-48+blaCTX-M-28, blaNDM-1+blaCTX-M-15+blaTEM-1+blaOXA-1+qnrS1+aac(6')-Ib-cr and blaNDM-1+blaCTX-M-15+blaTEM-1+qnrB1+aac(6')-Ib-cr genes were co-transferred and that these genes were carried by a conjugative plasmid of high molecular weight.
authors.affiliation: Molecular Bacteriology Laboratory, Pasteur Institute of Morocco, Casablanca, Morocco; Microbiology, Health and Environment Team, Department of Biology, Faculty of Sciences, Chouaib Doukkali University, El Jadida, Morocco.
authors.forename: Abouddihaj
authors.initials: A
authors.lastname: Barguigua
authors.affiliation: University Hospital Center Ibn Rochd, Casablanca, Morocco; Faculty of Medicine and Pharmacy, University Hassan II, Casablanca, Morocco. Electronic address: khalid.zerouali2000@gmail.com.
authors.forename: Khalid
authors.initials: K
authors.lastname: Zerouali
authors.affiliation: University Hospital Center Ibn Rochd, Casablanca, Morocco.
authors.forename: Khalid
authors.initials: K
authors.lastname: Katfy
authors.affiliation: Microbiology, Health and Environment Team, Department of Biology, Faculty of Sciences, Chouaib Doukkali University, El Jadida, Morocco.
authors.forename: Fatima
authors.initials: F
authors.lastname: El Otmani
authors.affiliation: Molecular Bacteriology Laboratory, Pasteur Institute of Morocco, Casablanca, Morocco.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Timinouni
authors.affiliation: University Hospital Center Ibn Rochd, Casablanca, Morocco; Faculty of Medicine and Pharmacy, University Hassan II, Casablanca, Morocco; Pasteur Institute of Morocco, Casablanca, Morocco.
authors.forename: Naima
authors.initials: N
authors.lastname: Elmdaghri
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002648:Child; D002675:Child, Preschool; D003227:Conjugation, Genetic; D003428:Cross Infection; D005260:Female; D006785:Hospitals, University; D006801:Humans; D007223:Infant; D007710:Klebsiella Infections / Q000453:epidemiology / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000235:genetics*; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009018:Morocco / Q000453:epidemiology; D015995:Prevalence; D055815:Young Adult; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D001618:beta-Lactamases; C552864:beta-lactamase NDM-1; C108449:oxacillinase
keywords: Carbapenemase; K. pneumoniae; Moroccan hospital; PFGE