THC Locks May Offer Edge to Dialysis Patients
ISTANBUL—Taurolidine-heparin-citrate (THC) line locks appear to be better than heparin line locks for preventing the recurrence of catheter-related bacteremia (CRB) in hemodialysis patients (HD), according to results released at the 50th Congress of the European Renal Association-European Dialysis and Transplant Association.
Richard Corbett, MD, a nephrologist at Imperial College Renal and Transplant Centre, London, U.K., and co-workers randomized patients within two weeks of the onset of bacteremia to either THC (containing heparin 500 units/mL) or heparin (5,000 units/mL) line locks following each dialysis for six months, in addition to standard antibiotic therapy.
The study included 27 patients with evidence of a CRB who were eligible for catheter salvage therapy and had been on HD for more than 90 days and were currently using a heparin line lock. The pre-specified primary outcome measure was the duration of bacteremia-free catheter survival at 180 days.
CRB is a cause of significant morbidity in patients maintained on long-term tunneled HD catheters for vascular access, Dr. Corbett noted. Catheter salvage involving antibiotic treatment without removal of the catheter is recommended for individuals without signs of systemic sepsis and who have a good initial response to antibiotics.
Taurolidine, which was developed in the 1970s as a broad-spectrum antibiotic, requires high concentrations for efficacy and is thus not suitable as a parenteral antibiotic. To date, there have been no reports of taurolidine-resistant organisms.
Taurolidine line locks have been shown to be effective in preventing catheter-related bloodstream infections in patients on home parenteral nutrition and in pediatric cancer patients. When used without heparin, however, taurolidine line locks have led to unacceptably high levels of catheter dysfunction in dialysis patients.
The two treatment groups in the U.K. study were similar with respect to baseline demographic and clinical characteristics.
The analysis showed significant improvement in bacteremia-free catheter survival in the cohort that had catheter salvage with THC lock. The researchers observed no cases of recurrent CRB in the 14-patient THC group, while six of 13 catheters were removed in the heparin group during the six-month study.
Dr. Corbett said that the trial was too small to reliably interpret pre-defined secondary outcome measures including hospital admissions for catheter- related problems such as catheter removal, erythropoietin resistance, and HD adequacy. He and his colleagues observed an increase in systemic thrombolytic use in the THC arm, but subsequent analysis out to 600 days from trial recruitment does not suggest that the reduction in bacteremia seen is “at the expense of” delayed catheter dysfunction, he added. He also emphasized that the study was conducted at a single center.
“For now, THC line locks should be used as an adjunctive therapy in the setting of catheter salvage,” Dr. Corbett said. “Their role as a standard line lock still needs to be clarified considering that the marked reduction in bacteremia may be offset by increased levels of catheter dysfunction given the use of a lower concentration of heparin than is conventionally used.”