Clinical Characteristics of Patients in the Intensive Care Unit with Infections Caused By Multiresistant Gram-Negative Bacteria

OBJECTIVES: To describe the clinical characteristic and treatment patterns in patients in the intensive care unit (ICU) with infections caused by multiresistant Gram-negative bacteria

METHODS: This is an observational, retrospective study in ICU patients with any of the following infections caused by resistant gram-negative bacteria: bacteremia, urinary tract, pneumonia, and intra-abdominal. It was performed in two Colombian hospitals and involved the review of medical records between 2018 to 2021. Patients were followed up until 30 days in the hospital, hospital discharge or death. Demographic and clinical characteristics, treatments and outcomes were abstracted.

RESULTS: On hundred sixty-two patients were included in the study. The mean age was 59.1 [Standard deviation (SD) 16.1], mainly males (59.9%). The most frequent diagnosis of ICU was community-acquired pneumonia (13.6%), primary bacteremia (9.9%), hospital-acquired pneumonia (8.6%), and intrabdominal infections (8.0%). The mean time in ICU was 27.6±33.5 days. The mean APACHE II score at the ICU admission was 40.8 (SD 23.9). Mechanical ventilation (MV) was required in 132 patients. The mean MV was 23.8±32.6 days. The main etiological causes of infection were K. pneumoniae (45.0%), E. coli (13.6%), P. aeruginosa (12.3%), and Enterobacter spp. (9.8). Carbapenemases were the most frequent mechanism of resistance (83.3%). The most frequent risk factors were central venous catheter (87.6%), use of urinary catheter (54.3%), septic shock (74.1%), previous hospitalization in the last 90 days (41.4%), and previous surgery in the last month (42.6%). Resulting in 67 deaths. Meropenem (54.3%), piperaciline tazobactam (22.5%), cefepime (19.9%), and polymyxin B (17.9%) were the most frequent antibiotics. Seventy-nine percent of antibiotics were used empiric.

CONCLUSIONS: Carbapenamases resistance and K. pneumoniae were the most frequent bacteria reported in studied population and empiric antibiotics regimens were most used to treat the infections.