Isolated pathogens, antimicrobial susceptibility, and clinical outcomes in intensive care unit patients at a tertiary hospital in Ethiopia: a retrospective cross sectional study.

backgroundAntimicrobial resistance (AMR) is a global public health threat associated with poor patient outcomes; however, there are major gaps in routine surveillance and reporting. In low-income countries like Ethiopia, antibiotics tend to be misused, particularly in intensive care units (ICU).

aimTo determine the bacterial profile, antimicrobial resistance patterns, and associated clinical outcomes among ICU patients at Tikur Anbessa Specialized Hospital (TASH), Addis Ababa.

methodsAn institution-based, six-month (May 1, 2023-October 31, 2023) retrospective cross-sectional study was conducted in the ICU of TASH on 216 patients. Data regarding sociodemographic and clinical characteristics, antimicrobial susceptibility testing (AST), and patient outcomes were collected from the health management information system (HMIS). Statistical Package for the Social Sciences (SPSS) version 27 was used for data analysis. Bivariate and multivariate logistic regression analysis were performed to assess the association between AMR and intra-ICU mortality. A p-value of < 0.05 was considered statistically significant.

resultsEighty nine point four percent of infections were due to Gram-negative bacteria. Of the Gram-negative isolates, the most commonly isolated pathogen was Acinetobacter baumannii (31.5%), followed by Klebsiella pneumoniae (22.7%), and Escherichia coli (14.8%). Acinetobacter baumannii was predominantly carbapenem resistant. Eighty point one percent of bacterial isolates exhibited multidrug resistance. The lowest level of resistance was observed with amikacin across all microorganisms. Bloodstream infections (BSIs) were the most frequently reported infection type. Intra-ICU mortality was determined to have a significant association with BSI (AOR 2.89, 95% CI 1.11, 3.94), septic shock (AOR 5.34, 95% CI 2.32, 12.25), CRAB infection (AOR 2.22, 95% CI 1.11, 4.43), and surgical intervention (AOR 0.46, 95% CI 0.24, 0.88).

conclusionThe study demonstrates a high burden of multi-drug resistant gram-negative infections in the ICU. The findings also show the clinical impact of AMR on mortality, particularly in critically ill patients with septic shock and BSI. The study highlights the urgent need to strengthen antimicrobial stewardship programs, enhance infection prevention and control practices, and improve microbiological surveillance systems in ICU settings.