Hamadan University of Medical Sciences Avicenna Journal of Clinical Microbiology and Infection 2383-0298 12 3 2025 09 24 Prevalence, Etiology, and Antimicrobial Resistance Pattern of Bacterial Isolates From Bloodstream Infections in Ganjavian Hospital, Dezful, Iran 115 120 10.34172/ajcmi.3647 EN Behnaz Deihim https://orcid.org/0000-0003-3716-6234 Ahmad Ali Assarian Mohammad Shoja Journal Article 10.34172/ajcmi.3647 2025 04 12 2025 07 02 Background: Sepsis is a life-threatening condition with high mortality rates. The emergence of antimicrobial resistance (AMR) among pathogens that cause sepsis poses a significant challenge to effective treatment. This study was conducted to determine the AMR patterns of bacterial isolates from septic patients’ blood cultures with emphasis on extended-spectrum beta-lactamases (ESBLs), carbapenemase, and methicillin-resistant Staphylococcus aureus (MRSA) prevalence. Methods: This cross-sectional laboratory study examined blood culture samples of 1248 patients. The blood cultures were subcultured on MacConkey and chocolate agar media. Bacterial identification was based on gram-staining and biochemical tests. Initial and confirmatory antibiotic susceptibility testing was then performed according to CLSI 2022 for MRSA, vancomycin-resistant Enterococcus (VRE), and ESBLs. The statistical analysis of the study findings was conducted using SPSS. The accuracy level of the evaluations was determined with a 95% confidence interval. Results: Among the 174 cases of bloodstream infection (BSI) (13.9% positivity), Enterobacterales (59.8%) and gram-positive cocci (32.7%) were dominant isolates. Interestingly, the prevalence of MRSA was 67.5%, with a significantly higher prevalence in ICUs (81.3%; P=0.037). In gram-negative isolates, resistance to third-generation cephalosporins and carbapenems was 48.7% and 22.2%, respectively. Significant resistance to carbapenems (80%) was observed in Acinetobacter isolates, but all strains remained susceptible to colistin. ESBL producers included Escherichia coli (36.3%) and Klebsiella pneumoniae (16%). Notably, 52.4% of multidrug-resistant Enterobacteriaceae cases were isolated from patients in emergency departments and intensive care units. Conclusion: This study highlights the alarming prevalence of MDR bacteria among sepsis isolates. Precautions should be taken against this growing threat by focusing on three priorities: enhancing infection control, maintaining continuous surveillance, and exploring novel therapeutic approaches.