Control of Gram-negative multi-drug resistant microorganisms in an Italian ICU: Rapid decline as a result of a multifaceted intervention, including conservative use of antibiotics

Abstract Background Gram-negative Multi-Drug-Resistant Organisms (GNMDROs) cause an increasing burden of disease in Intensive Care Units (ICUs). We deployed a multifaceted intervention to control selection and transmission of GNMDROs and to estimate at which rate GNMDROs would decline with our interventional bundle. Methods Interventions implemented in 2015: in-ward Antimicrobial-Stewardship-Program for appropriate management of antimicrobial prescription; infection monitoring with nasal/rectal swabs and repeated procalcitonin assays; 24 h microbiological support (since 2016); prevention of catheter-related infections, VAPs and in-ward GNMDROs transmission; education of ICU personnel. In May 2017, epidemiological, clinical and microbiological data were collected and retrospectively analyzed. Rates of resistance in Klebsiella pneumoniae , Pseudomonas aeruginosa and Acinetobacter baumannii , as well as percentages of resistance among all Gram-negative bacteria were compared during the study period. Results Of 668 patients, at least one isolate was obtained from 399 patients. The proportions of patients with infection and with Gram-negative isolates were even across the 5 semesters (p = 0.8). For Klebsiella pneumoniae , the number of strains resistant to carbapenems fell from 94% to 6% (p  Pseudomonas aeruginosa and Acinetobacter baumannii . Percentages of resistance for all Gram-negative isolates fell from 91% to 13% (p  Conclusions Our experience provides further evidence that a multi-faceted intervention, aimed to reduce selection and transmission of GNMDROs with efficient microbiological support, may yield remarkable results in a short time interval.