Nosocomial dissemination of Providencia stuartii isolates carrying bla OXA-48, bla PER-1, bla CMY-4 and qnrA6 in a Tunisian hospital

J Antimicrob Chemother. 2013 Feb;68(2):329-32. doi: 10.1093/jac/dks386. Epub 2012 Sep 26.


Objectives: To report an outbreak due to Providencia stuartii isolates carrying bla(OXA-48), bla(PER-1), bla(CMY-4) and qnrA6 in a Tunisian hospital in 2011.

Methods: Eight intensive care unit (ICU) patients infected/colonized by extended-spectrum β-lactamase (ESBL)-producing P. stuartii between March and May 2011 were included. Molecular epidemiology was studied by PFGE. Antibiotic resistance genes were analysed by PCR and sequencing and the plasmid incompatibility group by a PCR-based replicon typing scheme.

Results: Eight patients were colonized with ESBL-producing P. stuartii isolates. All these isolates were clonally related and found to carry bla(OXA-48), bla(PER-1), bla(CMY-4), qnrA6 and aac-6'-Ib genes on the same self-conjugative IncA/C plasmid. The same strain was also cultured from environmental samples in the ICU. All these isolates were susceptible to carbapenems. Only one colonized patient developed P. stuartii pleurisy and was effectively treated with imipenem alone.

Conclusions: This is the first report of an outbreak due to P. stuartii isolates carrying bla(OXA-48) in Tunisia. The simultaneous expression of various resistance genes (bla(OXA-48), bla(CMY-4), bla(PER-1), qnrA and aac-6'-Ib) by P. stuartii isolates is alarming.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Conjugation, Genetic
  • Cross Infection / epidemiology*
  • Cross Infection / microbiology
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • Disease Outbreaks*
  • Drug Resistance, Multiple, Bacterial*
  • Electrophoresis, Gel, Pulsed-Field
  • Enterobacteriaceae Infections / epidemiology*
  • Enterobacteriaceae Infections / microbiology
  • Environmental Microbiology
  • Female
  • Genes, Bacterial*
  • Hospitals
  • Humans
  • Intensive Care Units
  • Male
  • Middle Aged
  • Molecular Epidemiology
  • Molecular Typing
  • Plasmids
  • Polymerase Chain Reaction
  • Providencia / classification
  • Providencia / drug effects*
  • Providencia / genetics
  • Providencia / isolation & purification
  • Sequence Analysis, DNA
  • Tunisia / epidemiology
  • Young Adult


  • DNA, Bacterial