High Rate of Ceftobiprole Resistance among Clinical Methicillin-Resistant <i>Staphylococcus aureus</i> Isolates from a Hospital in Central Italy

Abstract

Ceftobiprole is a fifth-generation cephalosporin with activity against methicillin-resistant <i>Staphylococcus aureus</i> (MRSA). One-year surveillance at the Regional Hospital of Ancona (Italy) disclosed a 12% ceftobiprole resistance rate (12/102 isolates; MIC, ≥4 mg/liter). Epidemiological characterization demonstrated that the resistant isolates all belonged to different clones. Penicillin-binding protein (PBP) analysis showed substitutions in all PBPs and a novel insertion in PBP2a. The <i>mecB</i> and <i>mecC</i> genes were not detected. Ceftobiprole susceptibility screening is essential to avoid therapeutic failure and the spread of ceftobiprole-resistant strains.