Phenotypic Resistance of Ciprofloxacin and Azithromycin Resistant Campylobacter Isolates to an Extended Panel of Antibiotics.

Romaina Cachique, L.; Schiaffino, F.; Paredes Olortegui, M.; Manzanares Villanueva, K.; Pinedo Vasquez, T.; Castro, A.; Najarro, J.; Cooper, K.; Mourkas, E.; Pascoe, B.; Penataro Yori, P.; Parker, C. T.; Kosek, M. N.

doi:10.64898/2026.02.06.704332

bioRxiv · 10.64898/2026.02.06.704332

Phenotypic Resistance of Ciprofloxacin and Azithromycin Resistant Campylobacter Isolates to an Extended Panel of Antibiotics.

Romaina Cachique, L.·Schiaffino, F.·Paredes Olortegui, M.·Manzanares Villanueva, K.·Pinedo Vasquez, T.·Castro, A.·Najarro, J.·Cooper, K.·Mourkas, E.·Pascoe, B.·Penataro Yori, P.·Parker, C. T.·Kosek, M. N.

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Abstract

In this study we explored phenotypic resistance using traditional Kirby-Bauer methods in human and animal derived Campylobacter isolates that were concurrently resistant to both azithromycin and ciprofloxacin to an expanded panel of antimicrobials, including clindamycin, fosfomycin, ampicillin sulbactam and tigecycline. Out of 236 Campylobacter isolates, over 85% of C. jejuni and C. coli were resistant to clindamycin, over 60% were resistant to ampicillin sulbactam and over 30% to fosfomycin. Less than 2% of isolates were resistant to tigecycline and there was no observed resistance to Imipenem.

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Romaina Cachique, L., Schiaffino, F., Paredes Olortegui, M., Manzanares Villanueva, K., Pinedo Vasquez, T., Castro, A., Najarro, J., Cooper, K., Mourkas, E., Pascoe, B., Penataro Yori, P., Parker, C. T., Kosek, M. N.. 2026-02-10. Phenotypic Resistance of Ciprofloxacin and Azithromycin Resistant Campylobacter Isolates to an Extended Panel of Antibiotics.. https://doi.org/10.64898/2026.02.06.704332

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