Impact of Vancomycin trough levels monitoring on uncomplicated methilcillin-resistant Staphylococcus aureus bacteremia in chronic kidney disease on hemodialysis, retrospective cohort

Abstract

Background CKD patients on hemodialysis (HD) with Staphylococcus aureus (SA) bacteremia present high morbidity, mortality and increased risk of MRSA. Vancomycin is the antibiotic of choice in these cases, it has a narrow therapeutic margin and inadequate narrow therapeutic margin and inadequate dosage generates a risk of toxicity, therefore, they recommend that its dosage be guided through measurement of serum levels. Methods This is a retrospective cohort study in 3 hospitals of third level of complexity in the city of Medellin in which there were differences in the measurement and implementation of vancomycin25 dosage based on trough levels (VL) in patients with chronic kidney disease on hemodialysis (CKD- HD) with uncomplicated bacteremia based infection by methilcillin-resistant Staphyloccocus aureus (MRSA). The primary outcome was the composite of hospital mortality, clinical response (fever, hemodynamic instability and altered consciousness), complications associated with bacteremia or bacteriological response failure (positive cultures at first week follow-up) at 7 days, and the composite variables were analyzed individually as secondary outcomes. Results The main unadjusted outcome (OR 1.3, CI 0.6–2.7) and adjusted for age, Charlson index, loading dose, initial dose, dosing frequency and MIC to vancomycin (OR 1.2, CI 0.5–2.7). Regarding adjusted secondary outcomes: clinical response (OR 1.4 CI 0.3–5.8), death (OR 1.3 CI 0.3–4.6) and complications (OR 0.9, CI 0.37–2.2). Conclusions We conclude that the measurement of trough levels in patients with HD-CKD does not modify the composite outcome. The main limitation is the sample size and type of study, so that preferably randomized studies are required to confirm the results presented.