Clinical Risk Factors and Antimicrobial Resistance Patterns of Multidrug Resistant Enterobacter cloacae Isolates from Hospitalized Patients.

<ns3:p> Background <ns3:italic>Enterobacter cloacae</ns3:italic> is considered an important hospital-acquired pathogen associated with bloodstream, respiratory, and wound infections. Its increasing ability to acquire multidrug-resistant (MDR) traits poses a serious challenge for both infection control and therapeutic management. This study aimed to determine the antimicrobial resistance profiles, prevalence of MDR, and associated clinical risk factors of <ns3:italic>E. cloacae</ns3:italic> isolated from hospitalized patients. Methods Four hundred clinical specimens such as blood, pus, and sputum were collected between July 2024 and July 2025 from hospitalized patients suspected to have a bacterial infection. Risk-factor data were obtained through medical record review. Manual and automated identification with antimicrobial susceptibility testing were performed using the BD Phoenix™ automated microbiology system. Results Most infected patients with <ns3:italic>E. cloacae</ns3:italic> were male (64%) and aged 60 years or older (56%). Significant risk factors associated with MDR <ns3:italic>E. cloacae</ns3:italic> infections included prior antibiotic exposure (p = 0.008), hospitalization longer than 10 days (p = 0.021), and ICU admission (p = 0.034). All isolates (100%) were resistant to ampicillin, amoxicillin–clavulanate, cefazolin, and cefuroxime. Third- and fourth-generation cephalosporins (ceftazidime 70%, cefepime 70%, ceftriaxone 64%), along with ciprofloxacin (44%), levofloxacin (44%), and tigecycline (50%), showed high resistance rates, indicating reduced activity of major antibiotic classes. Imipenem resistance was detected in 34% of isolates, while amikacin (10%), meropenem (10%), and ertapenem (10%) retained good activity. Ceftolozane–tazobactam remained fully effective (100% susceptibility). The overall prevalence of MDR was 86%. Conclusion A high prevalence of MDR <ns3:italic>E. cloacae</ns3:italic> was identified among hospitalized patients, with strong associations to ICU stay, prolonged hospitalization, and prior antibiotic use. Despite widespread resistance to β-lactams and fluoroquinolones, ceftolozane–tazobactam, amikacin, meropenem, and ertapenem remain effective therapeutic options. The findings emphasize the importance of strengthening local antimicrobial stewardship programs and establishing region-specific surveillance data to guide empirical treatment and support infection-prevention strategies. </ns3:p>