No benefit of systematic hemodialysis catheter blood cultures for the early detection of catheter-related bloodstream infection

Background: The use of a catheter for hemodialysis is associated with a 5-fold increased risk of septicemia. Early detection of catheter-related bloodstrean infection (CRBSI) may decrease morbidity and mortality, but the benefits of systematic blood cultures have not been demonstrated. Materials and methods: We retrospectively studied the blood culture results of patients who had been dialyzed with a tunneled jugular catheter for more than 1 month in a dialysis unit from January to December 2015. Systematic monthly catheter blood cultures were taken from the heparin lock solutions in the arterial and venous branches, at the beginning or end of the session. CRBSI was assessed using patient symptoms (fever, chills, hemodynamic instability) and positive catheter blood cultures. Results: 75 patients were included. We analyzed the results of 577 systematic catheter blood cultures. 27 (5%) were positive, including 23 from patients who did not develop CRBSI in the following month. For the latter, there was a predominance of coagulase-negative staphylococci. Only four patients with positive catheter blood cultures went on to develop CRBSI in the following month. The sensitivity and specificity of these monthly blood cultures to detect CRBSI in the following month were 0.44 and 0.95, respectively. The positive and negative predictive values of the test were 0.14 and 0.99, respectively. Conclusion: In this study, systematic catheter blood cultures did not predict the occurrence of CRBSI. The sensitivity of these tests could be improved by increasing the sampling frequency. A cost-benefit analysis of such measures should be performed.