Comparison of ciprofloxacin, cotrimoxazole, and doxycycline on Klebsiella pneumoniae: Time-kill curve analysis

Background: Antibiotic resistance is a significant problem in the world, so optimization of antibiotic use is needed. Klebsiella pneumoniae is a Gram-negative bacterium that causes bacteremia, sepsis, UTIs, pneumonia, nosocomial infections and ESBL-producing bacterium. ciprofloxacin, cotrimoxazole, and doxycycline are broad-spectrum antibiotics, including in WHO essential drugs. Objective: The study tested antibiotics that most effectively inhibited Klebsiella pneumoniae non-ESBL, Klebsiella pneumoniae ESBL invitro with time-kill curve analysis. Method: This experiment used Klebsiella pneumoniae ATCC isolates, stored clinical isolates of Klebsiella pneumoniae non-ESBL, Klebsiella pneumoniae ESBL, and the control group. Isolates other than control were challenged with ciprofloxacin, cotrimoxazole, and doxycycline oral preparations with concentrations of 1, 2, 4 MIC at 0, 2, 4, 6, 8, 24 h. At each hour, the bacteria were cultured, incubated, calculated the number of colonies. The results were analyzed with time-kill curve and tested statistics. Statistical analysis used included ANOVA, post-Hoc, Mann Whitney, and Kruskal Willis tests with p < 0.05. Results: Ciprofloxacin, cotrimoxazole, and doxycycline in this study had inhibition effects on Klebsiella pneumoniae non-ESBL and Klebsiella pneumoniae ESBL. Ciprofloxacin had the best inhibitory effect. Statistically, the most meaningful differences of antibiotics in ciprofloxacin and cotrimoxazole at four and 24 h (p < 0.001), in concentrations of 1 MIC and 4 MIC at 2 h (p < 0.001), and in Klebsiella pneumoniae ESBL and Klebsiella pneumoniae ATCC at 8 h (p = 0.024). Conclusion: Ciprofloxacin is the best antibiotic to inhibit the growth of Klebsiella pneumoniae non-ESBL and Klebsiella pneumoniae ESBL compared to cotrimoxazole and doxycycline. The inhibitory effect increases with an increase in concentration.