Characterization of cefotaxime-resistant Escherichia coli isolates from a nosocomial outbreak at three geriatric hospitals

Emergence and Spread of Three Clonally Related Virulent Isolates of CTX-M-15-Producing Escherichia coli with Variable Resistance to Aminoglycosides and Tetracycline in a French Geriatric Hospital

“…CTX-M-type enzymes, whose presence is now described all over the world, appear to be a new challenge for the medical community, as they occur in a wide range of species and in clones of given species and plasmids, probably in relation to the fact that the corresponding genes are located downstream of an insertion sequence element (an ISEcp1-like element) which seems to act as a key factor in the dissemination of bla CTX-M type genes and as a strong positive factor for the expression of these genes (35). However, to our knowledge, outbreaks due to CTX-M-type enzyme-producing isolates have essentially been described so far in countries where CTX-Mtype-producing isolates are endemic, notably, Japan (20,26) and South America (37). The present article, which reports on the dissemination of clonally related CTX-M-15-producing E. coli strains in a French 650-bed geriatric hospital, might prefigure the near future for Western European countries, which now seem to be concerned with CTX-M-type enzymes.…”

“…They disseminated in the geriatric hospital, where the antibiotics prescribed most often were fluoroquinolones and ceftriaxone, but not in the affiliated acute-care hospital, where isolation precautions were applied to the transferred patients. Thus, E. coli isolates, both CTX-M-type ␤-lactamase producers and fluoroquinolone-resistant isolates, might present a new challenge for French health care settings.For the last 10 years, sporadically but regularly, the microbiology literature has reported on multidrug-resistant (MDR) bacteria in geriatric hospitals, long-term-care facilities, and nursing homes (14,26,30,44). The emergence of these bacteria in such health care facilities has become a public health concern because implementation of isolation precautions, which is the principal measure recommended in acute-care hospitals to avoid cross-transmission (12), is often considered deleterious for the quality of life of elderly people living in long-term-care facilities.…”

“…For the last 10 years, sporadically but regularly, the microbiology literature has reported on multidrug-resistant (MDR) bacteria in geriatric hospitals, long-term-care facilities, and nursing homes (14,26,30,44). The emergence of these bacteria in such health care facilities has become a public health concern because implementation of isolation precautions, which is the principal measure recommended in acute-care hospitals to avoid cross-transmission (12), is often considered deleterious for the quality of life of elderly people living in long-term-care facilities.…”

Molecular Characterization and Antimicrobial Susceptibility Testing of Escherichia coli Isolates from Patients with Urinary Tract Infections in 20 Chinese Hospitals

“…Plasmid size was determined by comparison to the known bands of Salmonella enterica serovar Braenderup by S1-PFGE, as described below. To locate the positions of small plasmids in isolates A012 and B233, Southern blot hybridization with CTX-M-1 and CTX-M-9 probes was carried out as previously described (27), with DNA digested by HindIII as a marker. Thirty-eight transformants bearing only a single plasmid harboring bla CTX-M were analyzed further by PCR-based replicon typing (PBRT) (4).…”

Biochemical characterisation of the CTX-M-14 β-lactamase

“…Table 1 shows all bacterial strains and plasmids used in this study. Escherichia coli TUM1121 was isolated from an abscess of an 83-year-old patient [18]. Escherichia coli TUM1121 shows resistance to penicillins, first-generation cephalosporins and cefotaxime (minimum inhibitory concentrations (MICs) ≥512 g/mL); however, this strain shows susceptibility to latamoxef, ceftazidime and imipenem (MICs ≤ 8 g/mL).…”