A Step Closer to Extreme Drug Resistance (XDR) in Gram-Negative Bacilli

Abstract

Much attention has been paid recently to the advent of extensive drug resistance in Mycobacterium tuberculosis. However, it is becoming clear that we are heading toward similarly extreme drug resistance (XDR) among gram-negative bacilli. The article by Tato et al. [1] in this issue of Clinical Infectious Diseases describes an ongoing outbreak of infection and colonization with metallo-β-lactamase (MBL)-producing gram-negative organisms that are not susceptible to almost all widely used antibiotics (susceptibility to tigecycline and polymyxins is not mentioned in their report). The authors report a situation that is perilously close to a state of endemicity, whereby untreatable organisms are entrenched in their institution. A mortality rate of almost 50% was observed among patients who were infected with MBL-producing organisms [1].