Udomsak Nakornnoi¹, Thitawat Wongampornpat¹, Siwat Santhitipong¹

Objective: To determine the prevalence and antimicrobial susceptibility pattern of bacteria isolated from urine culture in patients with acute uncomplicated cystitis in Vajira Hospital.

Materials and Methods: The cross-sectional study included 351 cases of acute uncomplicated cystitis between December 1, 2020, and December 31, 2021, at Vajira Hospital. All parameters and laboratory results were collected from the medical records.

Results: Escherichia coli was the most prevalent pathogen at 49.9%, followed by Klebsiella pneumoniae at 7.1% and Proteus mirabilis at 3.4%. Other identified pathogens included Staphylococcus saprophyticus at 1.7%, Streptococcus agalactiae at 1.4%, Corynebacterium at 1.2%, and miscellaneous others at 4%. Cephalosporins, with 52.7%, and fluoroquinolones, with 23.8%, were the most common treatments. Amoxicillin or clavulanic acid was the third most prescribed antibiotic at 10.8%, followed by fosfomycin at 8.0%, ertapenem at 2.0%, and trimethoprim/sulfamethoxazole (TMP/SMX) at 1.4%. Notably, E. coli exhibited high resistance to ampicillin for 73.1%, ciprofloxacin for 69.7%, TMP/SMX for 54.9%, and ceftriaxone for 30.3%. K. pneumoniae showed significant resistance to ampicillin for 88%, ciprofloxacin for 72%, and TMP/SMX for 40%). P. mirabilis demonstrated notable resistance to TMP/SMX for 58.3% and ciprofloxacin for 41.7%.

Conclusion: E. coli, K. pneumoniae, and P. mirabilis are the common pathogens in acute uncomplicated cystitis at Vajira Hospital. Given their high resistance to fluoroquinolones and TMP/SMX, alternative treatment options should be considered to address antimicrobial resistance effectively.

Received 24 March 2025 | Revised 28 April 2025 | Accepted 29 April 2025

DOI: 10.35755/jmedassocthai.2025.6.483-489-02811