Hidden Carbapenem Resistance in OXA-48 and Extended-Spectrum β-Lactamase-Positive Escherichia coli

The purpose of this study was to report the identification OXA-48 carbapenemase in seven extended-spectrum β-lactamase (ESBL)-positive Escherichia coli clinical isolates, fully susceptible to all carbapenems by disk diffusion and E-test methods, but with borderline minimal inhibitory concentration (MIC) values of ertapenem. This report points to the necessity for determination of carbapenem MICs in ESBL-positive E. coli isolates and additional phenotypic testing for carbapenemases in all isolates with borderline ertapenem MIC defined by EUCAST. The isolates showed a high level of resistance to expanded-spectrum cephalosporins because of the production of an additional ESBL belonging to CTX-M family. All isolates and their respective tranconjugants were found to possess L plasmid. Pulsed-field gel electrophoresis analysis revealed two clusters containing highly related isolates. The global spread of multidrug-resistant E. coli should be monitored closely because of the ability of isolates to rapidly obtain additional antibiotic resistance traits such as plasmid-mediated OXA-48 genes.

Expanding the use of noninvasive ventilation during an epidemic

Noninvasive ventilation (NIV) is a proved and effective therapeutic option for some patients with respiratory failure. During an epidemic, NIV can free up respirators and other intensive care unit equipment for patients with respiratory insufficiency whose survival depends exclusively on invasive ventilation. Some guidelines have indicated that NIV is potentially hazardous and should not be recommended for use during epidemics, given the perceived potential risk of transmission from aerosolized pathogen dispersion to other patients or medical staff. Conversely, some reports of previous epidemics describe NIV as a very efficient and safe modality of respiratory support, if strict infection control measures are implemented. We discuss NIV use during epidemics and indicate the need for prospective randomized clinical studies on the efficacy of NIV in epidemic conditions to provide important information to the current body of literature. Meanwhile, the use of NIV under strict infection control guidelines should be incorporated into epidemic preparedness planning.