ANTIMICROBIAL SUSCEPTIBILITY PROFILE OF ACINETOBACTER BAUMANNII ISOLATED FROM ICU AND NON-ICU PATIENTS AT NGOERAH HOSPITAL, BALI, INDONESIA: A RETROSPECTIVE STUDY IN 2025

Background: Acinetobacter baumannii is a major healthcare-associated Gram-negative pathogen and an important contributor to antimicrobial resistance. Institution-specific susceptibility data are useful for antimicrobial stewardship and infection-control planning. This study characterized the antimicrobial susceptibility of A. baumannii isolates recovered from ICU and non-ICU patients at Ngoerah Hospital during 2025.
Methods: Laboratory records from January through December 2025 were reviewed retrospectively. Only one A. baumannii isolate was counted for each patient, with the earliest specimen retained when more than one record was present. ICU status included ICU Timur, ICU Barat, and ICU IGD. Routine identification and susceptibility results were analyzed according to the 2025 CLSI M100, 35th edition.
The analysis included 437 unique isolates: 101 from ICU locations and 336 from non-ICU locations. Sputum accounted for 206 isolates (47.1%), while wound-base specimens accounted for 172 (39.4%). ICU isolates had their greatest susceptibility to trimethoprim/sulfamethoxazole (67.0%), amikacin (66.0%), and tigecycline (46.0%). In the non-ICU group, the corresponding figures were 68.7% for amikacin, 64.8% for trimethoprim/sulfamethoxazole, and 52.8% for tigecycline. Meropenem susceptibility was 47.0% and 52.5% in ICU and non-ICU isolates, respectively. None of the antimicrobial comparisons reached statistical significance (all Fisher’s exact p>0.05).
Conclusion: High levels of resistance were observed in both hospital locations. Because susceptibility did not differ significantly between ICU and non-ICU isolates, antimicrobial-resistance surveillance and stewardship should be implemented across the hospital rather than restricted to intensive care.