Treatment of dialysis catheter-related Enterococcus bacteremia with an antibiotic lock: a quality improvement report.

BACKGROUND: Catheter-related bacteremia (CRB) is a frequent complication of tunneled dialysis catheters, and Enterococcus is a common infecting organism. CRB may be treated by instilling an antibiotic lock into the catheter lumen in conjunction with systemic antibiotics. The efficacy of this approach in Enterococcus bacteremia is unknown.
DESIGN: Quality improvement report. SETTING & PARTICIPANTS: 64 catheter-dependent hemodialysis outpatients with vancomycin-sensitive Enterococcus bacteremia treated with a uniform antibiotic lock protocol. Clinical outcomes were tracked prospectively. QUALITY IMPROVEMENT PLANS: Patients received intravenous vancomycin for 3 weeks in conjunction with a vancomycin lock instilled into both catheter lumens after each dialysis session. MEASURES: Treatment failure was defined as persistent fever 48 hours after initiation of antibiotic therapy or recurrent Enterococcus bacteremia within 90 days. A clinical cure was defined as fever resolution without recurrent bacteremia. Major infection-related complications within 6 months were documented.
RESULTS: Treatment failure occurred in 25 patients (39%) because of persistent fever in 10 and recurrent bacteremia in 15. Treatment success occurred in 39 patients (61%). A serious complication of Enterococcus CRB occurred in 4 of 64 patients (6%); endocarditis in 1 and osteomyelitis in 3. The frequency of serious complications was 16% (4 of 25 patients) in those with treatment failure compared with 0% (0 of 39 patients) in those with treatment success (P = 0.01). LIMITATIONS: This was a single-center study. We did not measure serum vancomycin.
CONCLUSIONS: An antibiotic lock protocol permits catheter salvage in 61% of hemodialysis patients with Enterococcus CRB. Serious complications occur in 6% of patients and are more common in those with treatment failure.