Biofilm formation in long-term central venous catheters in children with cancer: a randomized controlled open-labelled trial of taurolidine versus heparin.

Taurolidine has demonstrated inhibition of biofilm formation in vitro. The aim of this study was to compare the effect of catheter locking with taurolidine vs heparin in biofilm formation in central venous catheters. Forty-eight children with cancer were randomized to catheter locking by heparin (n = 22) or taurolidine (n = 26), respectively. After removal, catheters were examined by standardized scanning electron microscopy to assess quantitative biofilm formation. Biofilm was present if morphologically typical structures and bacterial cells were identified. Quantitative and semi-quantitative cultures were also performed. Biofilm was identified in 23 of 26 catheters from the taurolidine group and 21 of 22 catheters from the heparin group. A positive culture was made of six of the catheters locked with taurolidine and heparin, respectively (p = 0.78). The rate of catheter-related bloodstream infections (CRBSI) was 0.1 per 1000 catheter-days using taurolidine and 0.9 per 1000 catheter-days using heparin (p = 0.03). This randomized trial confirmed that the use of taurolidine as catheter-lock compared with heparin reduced the rate of CRBSIs; this reduction was not related to a reduction in the intraluminal biofilm formation and the rate of bacterial colonization detected by scanning electron microscopy in the two groups.