Should we take into account ESBLs in empirical antibiotic treatment?

Excerpt

Gram-negative bacteria (GNB) are increasingly multidrug-resistant and represent a growing problem in critically ill patients who are particularly prone to infection. One of the most important resistance mechanisms of GNB are β-lactamases conferring resistance to β-lactam antibiotics by hydrolysation of their β-lactam ring [1]. Of the many different β-lactamases, ESBLs comprise the largest group of enzymes [1], causing resistance to various β-lactam antibiotics including third-generation cephalosporins and monobactams, but not carbapenems. Even in areas hitherto known for having minor resistance problems, 5–10 % of patients hospitalized in ICU wards on a given day harbour ESBL-producing Enterobacteriaceae in their gut flora [2]. Plasmids encoding ESBLs easily spread among Enterobacteriaceae, mainly Escherichia coli and Klebsiella pneumoniae [3]. …