Supplemental nutrients stimulate the amplification of carbapenemase-producing Klebsiella pneumoniae (CPKP) in a sink drain in vitro biofilm reactor model

Abstract

Liquid wastes (LW) disposed in hospital handwashing sinks may affect colonization of sink P-traps by carbapenemase-producing Klebsiella pneumoniae (CPKP), causing CPKP dispersal into the patient care environment. This study aimed to determine the effect of LW on biofilm formation and CPKP colonization in a P-Trap model (PTM). PTMs containing polymicrobial biofilms grown in autoclaved municipal tap water (ATW) supplemented with 5% dextrose in water (D5W), nutritional shake (Shake), sugar-based soft drink (Soda), or ATW were inoculated with K. pneumoniae ST258 KPC+ (ST258) or K. pneumoniae CAV1016 (CAV1016) and sampled after 7, 14, and 21 d. Biofilm bio-volume, mean thickness, and heterotrophic plate counts were significantly reduced and roughness coefficient significantly increased by Soda compared with D5W, Shake, or ATW. CPKP were significantly reduced by Soda but significantly amplified by D5W (ST258; CAV1016, 7 d) and Shake (ST258) suggesting that reducing LW disposal in sinks may reduce CPKP dispersal into patient care environments.

Keywords:

• Biofilm p-trap liquid waste Klebsiella pneumoniae polymicrobial biofilm

Acknowledgements

A.J.S. and L.K. were supported by a fellowship administered by ORAU through the US Department of Energy Oak Ridge Institute for Science and Education. The authors would like to thank Christine Ganim and Amanda Lyons for their assistance with sampling and Jonathan Edwards for assistance with data analysis. The use of trade names and commercial sources is for identification only and does not imply endorsement by the Public Health Service or the US Department of Health and Human Services. The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the US CDC.

Author contribution

M.L.B-G., S.K., and R.M.D. contributed to experimental design. M.L.B-G., A.J.S., and L.K. contributed to sample collection and analysis. M.L.B-G. S.K., and R.M.D. contributed to data analysis. M.L.B-G. and R.M.D. prepared the manuscript. All authors reviewed the manuscript.

Disclosure statement

All authors declare no competing interests.

Data availability

All data generated and analyzed in this study are available upon request to the corresponding author.