Bloodstream Infections Caused by Multidrug Resistant Bacteria: Clinical and Microbiological Features and Mortality.

Objectives: Bloodstream infections (BSI) are associated with high morbidity and mortality. The aim of our study is to determine whether there is a relationship between certain risk factors such as the underlying disease, patient's medical history, or interventional procedures and multidrug resistant (MDR) bacterial infection and to determine the risk factors for mortality.

Methods: Two hundred and twenty-two outpatients and inpatients who were diagnosed with bacteremia over a 6-month period were included in the study. 232 agents from 222 patients were isolated and tested for antimicrobial susceptibility. The relationship between patients demographic and clinical data and MDR was analyzed.

Results: The most common microorganisms were Gram-negative bacteria (59.4%), Gram-positive bacteria (36.9%), Candida species (2.2%), and anaerobic bacteria (1.35%). The most common isolates were Escherichia coli 53 (22.8%), Staphylococcus aureus 35 (%15.1), Klebsiella pneumoniae 26 (11.2%), Pseudomonas spp. (n=17, 7.3%), Acinetobacter spp 17 (7.3%), and Enterococcus spp 14 (6%). Microorganisms with the highest antimicrobial resistance observed were 82.3% in Acinetobacter baumannii, 64.5% in coagulase-negative staphylococci, 60.3% in E. coli, 50% in K. pneumoniae, and 27.2% in Enterobacterales spp. Most patients with BSI caused by MDR bacteria were in the intensive care unit (64%). Sepsis diagnosis, urinary catheter use, history of surgery, and use of broad-spectrum antibiotics as well as risk factors for antibiotic-resistant bacteremia, coronary artery disease, inappropriate empirical therapy, healthcare-associated infections, urinary catheterization, and stay in the ICU were determined as risk factors for mortality.

Conclusion: Our study identified the risk factors of BSI caused by MDR bacteria and helped to reveal the relationship between these factors and mortality.