Escherichia coli: Development of Carbapenem Resistance During Therapy

Abstract
A 76-year-old woman had recurrent urosepsis due to extended-spectrum β-lactamase-positive Escherichia coli. Imipenem resistance was detected after long-term imipenem-meropenem therapy. The carbapenem-hydrolyzing enzyme gene was identified as blaKPC-3. To our knowledge, this is the first documented case in which carbapenem-resistant E. coli emerged during therapy with imipenem and meropenem, and the first identification of the carbapenem-hydrolyzing enzyme in E. coli isolates.