ICU · antimicrobial-stewardship

MDR Organisms in ICU — Comprehensive (ESBL, CRE, MRSA, VRE, MDR-XDR TB)

Also known as MDR · XDR · PDR · Multidrug-resistant · Extensively drug-resistant · Pandrug-resistant · ESBL · CRE · MRSA · VRE · Carbapenemase · KPC · NDM · OXA-48 · Ceftazidime-avibactam · Antimicrobial stewardship · MDR-TB · XDR-TB

Multidrug-resistant (MDR) organisms in the ICU are the single greatest infectious threat to critically ill patients. The standardised definitions (Magiorakos 2012, ECDC and CDC international expert consensus): MDR is acquired non-susceptibility to at least one agent in three or more antimicrobial categories; XDR (extensively drug-resistant) is non-susceptibility to all but one or two categories; PDR (pandrug-resistant) is non-susceptibility to all agents in all categories. The four ICU core threats plus TB: ESBL (plasmid beta-lactamase CTX-M hydrolysing 3rd-generation cephalosporins, treated with a carbapenem); CRE (carbapenemases KPC serine, NDM and VIM and IMP metallo, OXA-48 — KPC to ceftazidime-avibactam, NDM to aztreonam plus CZA); MRSA (mecA, PBP2a, vancomycin or linezolid); VRE (vanA or vanB, linezolid or daptomycin); and MDR-TB (rifampicin plus isoniazid resistance, treated with the all-oral BPaL regimen). CRE bacteraemia carries 40 to 50 per cent mortality.