The Microorganisms Isolated from Blood Cultures of Intensive Care Patients and Follow-up of Antibiotic Susceptibilities in the Last Five Years

Abstract

Objective: Microorganisms isolated from blood cultures cause high morbidity and mortality. This study aimed to determine the antimicrobial resistance profiles of microorganisms isolated from blood cultures of patients hospitalized in intensive care units of a secondary-level state hospital.

Materials and Methods: Samples sent to the Microbiology Laboratory between 2018 and 2022 from patients receiving treatment in intensive care units of Nevşehir State Hospital were studied with conventional methods and the Vitek2 automated system, and the results of the samples for which identification and antimicrobial susceptibility tests were performed were evaluated retrospectively. SPSS 22 program was used to analyze the data, and categorical variables were expressed as numbers and percentages.

Results: Gram-negative bacteria growth was detected in 54.5% of all samples, gram-positive bacteria growth was detected in 40.7%, and yeast growth was detected in 4.8%;  Among gram-negative bacteria, Acinetobacter baumanni with a maximum of 28% (n = 47); Enterococcus faecalis was isolated as gram-positive bacteria with a maximum of 20.3% (n = 34). While vancomycin and linezolid resistance was not observed in all Enterococ isolates, The rate of methicillin resistance in CNSs was found to be 92.8% (26/28), and in Staphylococcus aureus, it was 33% (2/6). Extended-spectrum beta-lactamase (ESBL) positivity was detected in 72% (13/18) and 80% (20/25) of Escherichia coli and Klebsiella pneumonia isolates, respectively. Carbapenem resistance was observed in all A.baumanii isolates (100%), and all isolates were sensitive to colistin. The antibiotics E. coli and K. pneumonia were most sensitive to, and they were imipenem, meropenem (100%), and amikacin, respectively. The most sensitive antibiotics in all gram-positive isolates were linezolid and glycopeptide group.

Conclusion: To guide empirical treatment, each center should examine its own blood culture results, question the antimicrobial resistance status, and make rational antibiotic selection, aiming to reduce mortality in cases of sepsis and bacteremia.