Emergence of mutation-based linezolid-resistant invasive Enterococcus faecalis in a haemodialysis patient in Norway

摘要

Linezolid, an oxazolidinone antibiotic, has been available as a therapeutic alternative against antibiotic-resistant Gram-positive cocci since 2000. Linezolid inhibits bacterial protein synthesis by binding to the A site pocket at the ribosomal peptidyltransferase centre in domain V of the 23S rRNA genes. Point mutations in this region, in particular a G2576U mutation, have been associated with linezolid resistance in both enterococci and staphylococci [1, 2]. Recently, the first Enterococcus human isolate with plasmid mediated transferable linezolid resistance encoded by the cfr (chloramphenicol-florfenicol resistance) gene was recovered from a patient in Thailand [3]. Although resistance to linezolid in clinical isolates was reported prior to the release of the drug [4], surveillance programmes in both the US and Europe confirm that resistance rates remain very low [1, 2].