Antimicrobial resistance patterns of isolated bacteria at Bukoba Regional Referral Hospital in Patients attended from 2019 to 2023

BACKGROUND: Antimicrobial resistance (AMR) has emerged as a global public health concern, increasing morbidity, mortality, and healthcare costs. Limited surveillance data exist from regional referral hospitals in Tanzania, including Bukoba Regional Referral Hospital (BRRH). Understanding local AMR patterns is essential to guide empirical therapy and inform infection prevention and control strategies. This study aimed to determine the patterns, trends, and factors associated with AMR among bacterial isolates at BRRH between 2019 and 2023. METHODOLOGY: A retrospective cross-sectional study was conducted using laboratory records and patient files from Bukoba Regional Referral Hospital between January 2019 and December 2023. Clinical specimens were cultured, bacterial isolates identified using standard microbiological procedures, and antimicrobial susceptibility testing performed using the Kirby-Bauer disk diffusion method according to CLSI 2024 guidelines. Chi-square test was used to assess associations between bacterial isolates and prescribed antimicrobial agents, with statistical significance considered at P < 0.05. RESULTS: A total of 1,680 specimens were processed during the observation period, the proportion of specimens yielding pathogenic bacterial growth was 297 (17.7%) and 15 (0.9%) of culture samples were discarded due to contamination. The median age of patients was 28 years, with 58% female. Urine 110 (36.9%), pus 99 (33.2%), and stool 76 (25.5%) were the most common samples. Escherichia coli 60 (76.9%), Staphylococcus aureus 32 (86.5%), and Salmonella typhi 63 (100%) were the predominant isolates from urine, pus and stool samples respectively. E. coli showed high resistance to azithromycin (95.0%) and ampicillin (84.4%); S. aureus and coagulase-negative Staphylococci exhibited 100% and 90% resistance to penicillin, respectively. High levels of resistance to commonly used antimicrobial agents on Azithromycin 60 (88.2%), Ceftriaxone 118 (84.3%) and Ampicillin 82 (83.7%) were observed where 17.4% of patients were not prescribed antimicrobial agents despite culture positivity, while mismatches between susceptibility results and prescriptions were common. CONCLUSION: This study demonstrates a high prevalence of antimicrobial resistance among commonly isolated bacterial pathogens at Bukoba Regional Referral Hospital. Routine development of local antibiograms, strengthening antimicrobial stewardship programs, promoting rational antibiotic prescribing, and enhancing IPC practices are urgently needed to combat AMR at BRRH and similar settings.