Application of Vancomycin Therapeutic Drug Monitoring in a Vietnamese Private Hospital

Abstract

Vancomycin is a primary regimen for treating MRSA and other Gram-positive $\upbeta$-lactam–resistant organisms. But the problem is the resistance to vancomycin, the clinical and microbiological characteristics in which it is used is always changing. Therefore, we conducted this retrospective study to analysis benefits of Vancomycin TDM in clinical outcomes and discovered the factors affecting on the vancomycin maintenance dose. We conducted a follow-up on 137 patients using vancomycin divided into two groups, including the TDM and non-TDM users. The evaluation criteria included panoramic vancomycin use, infection status, renal function and treatment results after ten days. The total number of samples taken from 79 patients applied TDM were 116 and 73.3% of the samples reached the target trough concentration. Compared to 58 patients of the non-TDM group, applying TDM will reduce c-reactive protein (CRP) and improve treatment outcome. We also found that the vancomycin trough concentration, creatinine clearance, and weight contributed significantly (24.7%, 16.8% and 26.6%, respectively) to the inter-individual variability in vancomycin dose. The multiple linear regression model for vancomycin maintenance dose was built as the formula: Vancomycin maintenance dose (mg/kg) = 21.4 + 0.24 * vancomycin trough concentration (µg/mL) + 0.17 * Clcr(mL/min) − 0.26 * weight(kg) + 0.17 * age(years) − 0.03 * ΔCRP. Our study demonstrated the benefits of vancomycin TDM technology on clinical outcomes and improvement of infection situation. Furthermore, we have successfully indicated a strong relationship between vancomycin trough concentration, creatinine clearance, age, weight, ΔCRP and maintenance dose of vancomycin. Clinicians in the process of designing a regimen dose of vancomycin should comprehensively consider these factors in order to optimize the dose and reduce the adverse effect of vancomycin.