beta-Lactams without a suicide inhibitor.

Existing clinical studies concerning the impact of therapy with third-generation cephalosporins or cefepime on infections caused by extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae are retrospective, non-randomised, and have been carried out with a small number of patients and low-dosage schedules that lack PK-PD correlations with clinical efficacy. Rates of clinical failure and mortality are higher than those in studies with non-ESBL- producing Enterobacteriaceae. Therefore, in settings with a high prevalence of ESBL-producing Enterobacteriaceae, empirical therapy with advanced cephalosporins should be avoided. Temocillin, an old beta-lactam that is stable in the presence of both ESBLs and AmpC beta-lactamases, seems to deserve revival, although clinical data are limited.