Abstract :
Background: Treating physicians consistently face a tough challenge in treating the conditions caused by Multi drug resistant (MDRO) older antimicrobial like fosfomycin is re-established as effective alternatives for managing the infections caused by these pathogens, but limited information exists on their action against clinical isolates from specimens other than urine. So, this study aimed to assess the effectiveness of fosfomycin against Enterobacterales resistant to multiple drugs isolated from various clinical specimens and to comparatively evaluate the antimicrobial testing methods for fosfomycin like disk diffusion, agar dilution and micro broth dilution by Vitek-2.
Materials and Methods: Fosfomycin susceptibility testing was carried out for 550 clinical isolates by agar dilution, disk diffusion and Vitek-2 for a period of one year. Results of disk diffusion and Vitek-2 was compared with agar dilution.
Results: The study compared fosfomycin susceptibility testing using Vitek-2 (V2) and Disk diffusion (DD) against the reference Agar dilution (AD) method. V2 showed 83% Categorical agreement (CA) but had a 5% Very major error (VME), misclassifying resistant strains as susceptible. It also had 1.09% Major Error (ME) and 11% Minor error (mE). In contrast, DD performed better with 90% CA, lower VME (1.27%), ME (7%), and mE (1%). Overall, DD was more reliable than V2, with fewer critical errors, making it the preferred method for fosfomycin susceptibility testing.
Conclusion: According to the results of our study, fosfomycin has a good antimicrobial activity against MDR Enterobacterales and adoption of the disk diffusion method for routine testing of fosfomycin susceptibility, is both practical and feasible in healthcare settings where resource availability is limited.
Keyword :
Multidrug resistant, Fosfomycin, Agar dilution, Vitek-2, Disc diffusion.