Impact of the MIC of Piperacillin-Tazobactam on the Outcome of Patients with Bacteremia Due to Extended-Spectrum-B-Lactamase- Producing Escherichia coli

Abstract

We investigated the impact of the piperacillin-tazobactam MIC in the outcome of 39 bloodstream infections due to extended- spectrum-B-lactamase-producing Escherichia coli. All 11 patients with urinary tract infections survived, irrespective of the MIC. For other sources, 30-day mortality was lower for isolates with a MIC of <2 mg/liter than for isolates with a higher MIC (0% ver- sus 41.1%; P = 0.02