Antibiotic Resistance Among Gram-Negative Bacteria Isolated from Urinary Tract Infections

• Alaa Mohammed Shihab

  Department of Microbiology, Department of Microbiology, Umm Marzam General Hospital, Libya

  Author

• Salma O Jadallah

  Department of Botany, Faculty of Science, Omar Al-Mukhtar University, Al-Bayda, Libya

  Author

• Ismail saad

  Faculty of Life Sciences, Libyan Academy, AL-Jabal Al-Akhdar Branch, Libya.

  Author

Background: Urinary tract infections (UTIs) are among the most common infections worldwide, usually caused by Gram-negative bacteria such as Escherichia coli and Klebsiella pneumoniae. The rise of multidrug resistance has made treating these infections more challenging. Objective: This study aimed to identify the prevalence and antibiotic resistance patterns of Gram-negative bacteria causing UTIs at Umm Marzam General Hospital. Methods: Between December 2024 and February 2025, we collected 50 urine samples from patients suspected of having UTIs. We identified bacterial isolates using standard microbiological and biochemical tests and performed antibiotic susceptibility testing with the Kirby-Bauer disk diffusion method following CLSI guidelines. Results: The most common isolates were E. coli (76%), Klebsiella spp. (17%), and Proteus spp. (9%). We found high levels of resistance to ampicillin (>60%), trimethoprim-sulfamethoxazole (>50%), and ciprofloxacin (>40%). Nitrofurantoin and fosfomycin showed the best results, with susceptibility rates above 70%. Many isolates demonstrated multidrug resistance. Conclusion: This study shows high rates of antibiotic resistance among Gram-negative uropathogens at Umm Marzam Hospital, limiting treatment options. The results highlight the urgent need for routine susceptibility testing and antimicrobial stewardship programs to support effective treatment and prevent the spread of resistant strains.

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