Antimicrobial susceptibility of Campylobacter jejuni and Campylobacter coli: comparison between Etest and a broth dilution method

Background: Campylobacter is a leading cause of foodborne gasteroenteritis worldwide. Antimicrobial susceptibility testing for Campylobacter spp. is not routinely performed by most clinical laboratories. However, the emergence of resistant isolates strengthens the importance of antimicrobial susceptibility testing and the critical need for epidemiologic surveillance. The aim of this study was to compare the efficacy of Etest and Sensititre kit (a broth microdilution method) as methods for susceptibility tests and the critical need for epidemiologic surveillance. The aim of this study was to compare the efficacy of Etest and Sensititre kit (a broth microdilution method) as methods for susceptibility testing of Campylobacter spp. to tetracycline, erythromycin, and ciprofloxacin. Methods: Sixty-six Campylobacter isolates were collected from feces samples and subjected to susceptibility testing by Etest and Sensititre, a broth microdilution kit for tetracycline, erythromycin, and ciprofloxacin. Minimal inhibitory concentration (MIC) results of each method were determined and compared. Results: Similar MIC interpretations for tetracycline, erythromycin, and ciprofloxacin were found in 97%, 98.5%, and 100% of the isolates, respectively, indicating a good level of agreement between Etest and Sensititre (p < 0.0001); additionally, the correlation between the two methods was highly significant for the three tested antibiotics (p < 0.0001). Conclusions: Both the broth microdilution and the Etest are reliable and convenient methods for testing antimicrobial susceptibility of Campylobacter spp. The Sensititre kit has the advantages of high availability and the automation.