Transmission of extended-spectrum β-lactamase-producing Klebsiella pneumoniae associated with sinks in a surgical hospital ward, confirmed by single-nucleotide polymorphism analysis

Abstract

Although sink- and drain-related carbapenemase-producing Enterobacterales transmission has been reported previously, there is limited research regarding the transmission of extended-spectrum β-lactamase (ESBL)-producing Enterobacterales. To investigate nosocomial ESBL-producing Klebsiella pneumoniae transmission via patient sinks and drains on a general surgical hospital ward. ESBL-producing K.pneumoniae transmission on a surgical ward at Tokyo Medical University Hospital (built in July 2019) from July 2019 to February 2020 was investigated. Information regarding the relatedness of the isolates from the patients and the environment was provided by whole-genome sequence analysis. Four clinical isolates of K.pneumoniae (TUM19831, TUM19832, TUM19833 and TUM19834) were detected during the study. TUM19831 was identified prior to moving to the new building and was detected again in the new building. TUM19832 and TUM19833 were detected in July 2019, and TUM19834 was detected in December 2019. TUM19835 and TUM19836 were detected in two different sinks and drains in July 2019, while a further two sinks and drains tested positive for TUM19837 and TUM19838 in February 2020. Whole-genome analysis revealed that all strains were ST307 and CTXM15 sequence types, and the isolates were indistinguishable by genetic analysis. Due to inadequate removal of the slime biofilm coating, the sinks needed to be cleaned again before TUM19837 and TUM19838 could be detected. This study demonstrated the transmission of indistinguishable ESBL-producing K.pneumoniae strains from sinks and drains in the patient area of a general surgical hospital ward. There is a need to recognize this risk and develop optimal management strategies for plumbing systems in hospitals and other healthcare settings.