Variable Chlorhexidine Tolerance Across Klebsiella Species from a Single Facility

Lehman, D.; Hetzler, A. E.; Friedrich, T.; Strouse, M. M.; Barry, K. E.; Kotay, S.; Mathers, A.

doi:10.1101/2025.09.22.677961

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bioRxiv · 10.1101/2025.09.22.677961

Variable Chlorhexidine Tolerance Across Klebsiella Species from a Single Facility

Lehman, D.·Hetzler, A. E.·Friedrich, T.·Strouse, M. M.·Barry, K. E.·Kotay, S.·Mathers, A.

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Abstract

We assessed in vitro chlorhexidine tolerance across Klebsiella species from a hospital with widespread chlorhexidine use. Isolates underwent MIC testing and whole genome sequencing. Klebsiella species showed varying tolerance, with K. quasipneumoniae having the highest MICs. No clear link to acquired resistance was found, though chromosomal efflux pumps appeared in some traditionally environmental species. Differences in chlorhexidine tolerance between species highlight the role that biocides could have in shaping microbial populations in the hospital environment.

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Lehman, D., Hetzler, A. E., Friedrich, T., Strouse, M. M., Barry, K. E., Kotay, S., Mathers, A.. 2025-09-23. Variable Chlorhexidine Tolerance Across Klebsiella Species from a Single Facility. https://doi.org/10.1101/2025.09.22.677961

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