COMPARISON OF ANTI-MICROBIAL SUSCEPTIBILITY OF AZITHROMYCIN AND LEVOFLOXACIN AGAINST Pseudomonas aeruginosa AND Salmonella typhi

Abstract

Background and Objective: It is a bleak realty that antibiotics resistance resulted in the death of thousands of individuals every year around the world. Therefore, the aim of current study was to compare the sensitivity and resistance patterns of two common bacteria, Pseudomonas aeruginosa and Salmonella typhi against azithromycin and levofloxacin.

Methodology: An in-vitro comparative experimental study conducted in the Pharmaceutical Microbiology Lab., Faculty of Pharmacy, Hamdard University and Pathology Lab. of Husaini Hematology & Oncology Trust from May-2024 to October-2024. Collected isolates were 160; 75 (46.9%) Pseudomonas aeruginosa and 85 (53.1%) Salmonella typhi. These isolates have been obtained from blood, ear swabs, pus, urine and tracheal aspiration. Kirby-Bauer disc diffusion method was used for the antimicrobial susceptibility testing.

Results: Activity patterns of 15 mcg azithromycin (33.8%) and 5 mcg levofloxacin (66.2%) were noted; where 4 (2.5%) samples of P. aeruginosa exhibited sensitivity to azithromycin while 42 (26.3%) samples of P. aeruginosa showed sensitivity for levofloxacin. Meanwhile, 27 (16.9%) samples of S. typhi displayed as sensitive to azithromycin, but 28 (17.5%) samples S. typhi gave sensitive results towards levofloxacin. Mean zone of inhibition of P. aeruginosa was comparable (t=-1.624; p=0.109) by levofloxacin and azithromycin. However; for S. typhi levofloxacin was significantly better (t=-11.415; p=0.0001) compared to azithromycin.

Conclusion: The antimicrobial sensitivity of levofloxacin is higher than azithromycin. This clarifies that azithromycin should not be the first choice to treat infections against P. aeruginosa and S. typhi