Dissemination and genetic support of broad-spectrum beta-lactam-resistant strain isolated from two Tunisian hospitals during 2004-2012.

Background: The dissemination of extended-spectrum β-lactamase (ESBL)-producing bacteria presented a great concern worldwide. Gram-negative organisms such as and are the most frequently isolated pathogens responsible for nosocomial infections.

Objectives: The aim of this study was to investigate and to follow the emergence of resistance and the characterization of Extended-Spectrum Beta-Lactamases (ESBL) among broad-spectrum beta-lactam- clinical isolates recovered from the military hospital and Habib Thameur hospital in Tunisia.

Nosocomial dissemination of plasmids carrying blaTEM-24, blaDHA-1, aac(6')-Ib-cr, and qnrA6 in Providencia spp. strains isolated from a Tunisian hospital.

The aim of this study is to report the emergence of IncA/C conjugative plasmids harboring blaTEM-24, blaDHA-1, qnrA6, and aac(6')-Ib-cr genes among Providencia spp. isolates recovered in 2008 in Tunisia. The double-disk synergy test confirmed the phenotype extended-spectrum β-lactamase (ESBL) in 2 Providencia stuartii and 5 Providencia rettgeri.

First characterization of a Providencia stuartii clinical isolate from a Tunisian intensive care unit coproducing VEB-1-a, OXA-2, qnrA6 and aac(6')-Ib-cr determinants.

A clinical Providencia stuartii isolate SM662 was recovered from a patient hospitalized in the intensive care unit at the Military hospital, Tunisia. This isolate was resistant to penicillins, cephalosporins, aminoglycosides and fluoroquinolones. A marked in vitro synergy between ceftazidime or cefotaxime and amoxicillin-clavulanic acid on Mueller-Hinton agar plates suggested the presence of an extended-spectrum-β-lactamase.

Prevalence of quinolone resistance determinant qnrA6 among broad- and extended-spectrum beta-lactam-resistant Proteus mirabilis and Morganella morganii clinical isolates with sul1-type class 1 integron association in a Tunisian Hospital.

Objectives: The aim of this study was to investigate the prevalence and the emergence of plasmid-mediated quinolone resistance among broad-spectrum beta-lactam-resistant Proteus mirabilis and Morganella morganii clinical isolates recovered in the Military Hospital in Tunisia.

Methods: Of 200 strains examined, 50 exhibited resistance to quinolones. Quinolone resistance determinants (qnr and aac(6')-Ib-cr) were characterized by multiplex PCR and sequencing.

Chromosomal blaCTX-M-₁₅ associated with ISEcp1 in Proteus mirabilis and Morganella morganii isolated at the Military Hospital of Tunis, Tunisia.

This study investigated the genetic environment of bla(CTX-M) genes and associated resistance genes in seven Proteus mirabilis and six Morganella morganii extended spectrum β-lactamase (ESBL)-positive isolates. The isolates were recovered from hospitalized patients with respiratory or urinary tract infections at the Military Hospital of Tunis, Tunisia. Twenty-one of the 200 strains exhibited non-susceptibility to third generation cephalosporins and, among these strains, the double-disk synergy test confirmed the ESBL phenotype in 13 isolates.