The effect of taurolidine on the time-to-positivity of blood cultures

Background:Taurolidine containing lock solutions (TL) are a promising method for theprevention of central line associated bloodstream infections. Per accident, the TL may notalways be aspirated from the central venous catheter (CVC) before blood cultures areobtained. The TL could, unintentionally, end up in a blood culture vial, possibly alteringthe results. The aim of this study was to investigate the effect of the TLs on the detectionof microbial growth in blood culture vials. Methods:Different lock solutions (taurolidine-citrate-heparin (TCHL), taurolidine, hep-arin, citrate or NaCl) were added to BD BACTECTMblood culture vials (Plus Aerobic/F,Lytic/10 Anaerobic/F or Peds Plus/F) before spiking withStaphylococcus aureus(ATCC29213 or a clinical strain) orEscherichia coli(ATCC 25922 or a clinical strain) in thepresence and absence of blood. Subsequently, blood culture vials were incubated in theBD BACTEC FX instrument with Time-to-positivity (TTP) as primary outcome. In addition,the effect of the TCHL on a variety of other micro-organisms was tested. Discussion:In the presence of taurolidine, the TTP was considerably delayed or vials evenremained negative as compared to vials containing heparin, citrate or NaCl. This effectwas dose-dependent. The delayed TTP was much less pronounced in the presence ofblood, but still notable. Conclusion:This study stresses the clinical importance of discarding TLs from the CVCbefore obtaining a blood culture. (c) 2024 The Authors. Published by Elsevier Ltdon behalf of The Healthcare Infection Society. This is an open access articleunder the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).