Objective: Studies show that 30% to 60% of antibiotics prescribed in Intensive Care Units (ICUs) are unnecessary and inappropriate. Tailored antibiotic stewardship, infection control, and prevention measures should be implemented based on their own local epidemiology and healthcare possibilities.

Materials and Methods: We conducted an observational retrospective study in the General and Neurosurgery ICUs in Ospedale “dell’Angelo”, Venice. We collected microbiological data about Klebsiella pneumoniae from our local microbiology analysis laboratory and antibiotic consumption from the local pharmacy ward from January 2021 to December 2023.

Results: 377 K. pneumoniae strains were isolated: 225 (59.7%) in 2021, 108 (28.6%) in 2022 and 44 (11.7%) in 2023. Extended-spectrum β-lactamases (ESBL) isolates were 201/225 (89.8%) in 2021, 98/108 (90.7%) in 2022 and 24/44 (54.5%) in 2023. Meropenem (MEM)-resistant K. pneumonae were 121/225 (54.0%) in 2021, 69/108 (64.0%) in 2022, and 3/44 (9.0%) in 2023. In 2021, 94 patients tested positive for carbapenem-resistant K. pneumoniae (CRKp), 32/94 (34.0%) at admission, and 62/94 (66.0%) during the hospitalization. In 2022 and 2023, 68 patients were colonized by CRKp: 26/68 (38.2%) at admission and 42/68 (61.8%) during the recovery. Carbapenems consumption decreased from 1,536.5 defined daily dose (DDD) in 2021 to 744.9 DDD in 2023. From 2021 to 2023, Fluoroquinolones (F.Q.) decreased from 345.0 DDD to 145.0 DDD.

Conclusions: Our study shows that tailored and implemented infection control and antibiotic stewardship measures could profoundly impact CRKp transmission in the ICU.