Assessment of Colistin Heteroresistance among Multidrug-Resistant Isolated from Intensive Care Patients in Europe.

Heteroresistance (HR) to colistin is especially concerning in settings where multi-drug-resistant (MDR) are prevalent and empiric use of colistin might lead to treatment failures. This study aimed to assess the frequency of occurrence of colistin HR (CHR) among (MDR) ( = 676) isolated from patients hospitalized in 13 intensive care units (ICUs) in six European countries in a clinical trial assessing the impact of decolonization strategies. All isolates were whole-genome-sequenced and studied for in vitro colistin susceptibility.