NPPA and infection: Our study showed that particular attention should be drawn to the use of a few antibiotic classes that may play a role in infections sustained by MDR-Kp: specifically, we found that previous exposure to aminoglycosides, linezolid, penicillins, and colistin increases the likelihood of infection onset among ICU patients, together with a hindering effect of a combined exposure to penicillins and linezolid or colistin.