Managing Dialysis Catheter–Related Staphylococcus aureus Bacteremia

In their retrospective study, Maya et al1 report the routine use of antibiotic lock solution in treating dialysis catheter–related Staphylococcus aureus bacteremia to be inappropriate. We read the article with great interest and agree with the conclusions, but have some concerns regarding the study design and definitions used.

Early catheter-related bacteremia can be treated either with antibiotic lock solution or catheter exchange over a guidewire as per KDOQI clinical practice recommendations.2 A third option of removal of the infected catheter and replacement after a catheter-free period and negative blood cultures can be implemented if the clinical situation demands it. A better study design would be one in which patients were randomized to either of these first 2 treatment modalities.

Secondly, a sample drawn from the dialysis catheter during the dialysis session is inappropriate. The presence of a biofilm in the catheter can contaminate any blood that flows through the catheter lumen. Moreover, the authors do not mention the reuse policy in their units, as blood samples obtained from the dialysis tubing connected to reused dialyzers can be contaminated too. We agree with the concerns that obtaining a peripheral blood sample in individual dialysis patients may be difficult, but certainly this is not the case in the entire dialysis population.