Trough serum vancomycin levels predict the relapse of gram-positive peritonitis in peritoneal dialysis patients

Area of Science:

• Nephrology
• Infectious Diseases
• Pharmacology

Background:

• Peritonitis is a common complication in peritoneal dialysis (PD).
• Gram-positive bacteria are frequent causative agents of peritonitis in PD patients.
• Peritonitis relapse poses a significant challenge in managing PD-associated infections.

Purpose of the Study:

• To identify risk factors for peritonitis relapse in peritoneal dialysis patients.
• To investigate the relationship between vancomycin trough levels and peritonitis relapse.
• To evaluate the utility of early vancomycin trough levels as a marker for relapse.

Main Methods:

• Retrospective review of 31 gram-positive peritonitis episodes in PD patients (1990-1993).
• Patients received 4 weekly intravenous vancomycin doses, with adjustments to maintain trough levels >12 mg/L.
• Comparison of characteristics between relapse-prone and relapse-free episodes, focusing on vancomycin levels.

Main Results:

• Nine episodes of peritonitis relapse were identified.
• Episodes preceding relapse had significantly lower cumulative 4-week mean trough vancomycin levels (7.8 mg/L) compared to relapse-free episodes (13.7 mg/L).
• Relapses occurred in 9/14 episodes with mean trough levels <12 mg/L versus 0/17 episodes with levels >12 mg/L (P<0.05).
• Low initial 7-day trough vancomycin levels (<9 mg/L) were associated with subsequent relapse (9/13 episodes).

Conclusions:

• Inadequate trough vancomycin levels are a significant risk factor for gram-positive peritonitis relapse in PD patients.
• Maintaining target trough vancomycin levels (>12 mg/L) is critical for preventing peritonitis recurrence.
• Monitoring initial vancomycin trough levels can help identify patients at higher risk for relapse.