Comparative analysis of novel suspension testing and agar cup diffusion methods in establishing the susceptibility of Pseudomonas aeruginosa against ethanol and chlorhexidine gluconate

Abstract

Pseudomonas aeruginosa is one among the leading nosocomial pathogens worldwide. It is therefore necessary to decrease and to prevent a rebound of growth. Comparison of novel suspension testing method and agar cup diffusion method results in determination of the sensitive method to identify effectiveness of disinfectants against microbial activity. This study was carried out to determine the effectiveness among novel suspension testing and agar cup diffusion method to determine disinfectant susceptibility and also to identify the efficacy of ethanol and chlorhexidine gluconate at manufacturer’s concentration against Pseudomonas aeruginosa.  In this study 50 isolates of Pseudomonas aeruginosa  were included. Each isolate was subjected to novel suspension testing method and agar cup diffusion method with ethanol and chlorhexidine gluconate, the results were observed and recorded. The 50 isolates, sensitive strains showed 100% sensitivity to chlorhexidine gluconate and 95% to ethanol. Whereas resistant strains showed 100% sensitivity to chlorhexidine gluconate, 75% were sensitive to ethanol. Both agar cup diffusion method and novel suspension method yielded similar results. With the advantage of easy processing and less time consumption, agar cup diffusion method can be routinely used for determining the disinfectant susceptibility testing.