Enterobacteriaceae producing ESBLs in the community : Are they a real threat?

Organisms that produce extended-spectrum β-lactamases (ESBLs) remain an important cause of failure of therapy with cephalosporins and have serious infection control consequences. Klebsiella pneumoniae and Escherichia coli remain the major ESBL-producing organisms isolated worldwide. Klebsiella species that produce ESBLs (such as the SHV and TEM types) are a major cause of hospital-acquired infections, while E coli that produce ESBLs (the CTX-M enzymes) have emerged as an important cause of community-onset urinary tract infections in some areas. These bacteria are often associated with resistance to other classes of antibiotics, especially the fluoroquinolones. A heightened awareness of clinicians and the enhanced testing by laboratories, including molecular surveillance studies, are required to reduce treatment failures, limit the introduction of these bacteria into hospitals, and prevent the spread of these emerging pathogens.