Related Experiment Video
Updated: Jul 5, 2026

Nanomechanics of Drug-target Interactions and Antibacterial Resistance Detection
Published on: October 25, 2013
Vancomycin penetration into intra-abdominal compartments: Site concentration disparities and implications for dose
Huifang Zhang1, Yaxin Fan2, Fangqing Zhou1
1Department of Critical Care Medicine, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Objective:
To characterize vancomycin penetration into intra-abdominal infection sites (ascites and bile) in critically ill patients with Gram-positive complicated intra-abdominal infection (cIAI), and to explore whether incorporating site-specific therapeutic drug monitoring (TDM) is associated with better clinical outcomes compared to standard serum TDM alone.
Methods:
This prospective, single-center observational cohort study enrolled ICU patients with Gram-positive cIAI from 2021 to 2024. All patients received vancomycin administration and underwent TDM of serum drug concentrations (serum-only group), while a subset of patients also underwent TDM of the infection site fluid (bile/ascites, dual-TDM group).
Primary Outcome:
vancomycin TDM concentration and target attainment among the cIAI patients.
Secondary Outcomes:
Efficacy and safety among the two groups, and vancomycin penetration in bile/ascites.
Results:
A total of 39 patients were included in this study, with 25 in dual-TDM and 14 in serum-only TDM. Serum trough concentration (Cmin) was 12.04 (8.60-15.87) mg/L and area under the concentration-time curve over 24 hours/ minimum inhibitory concentration (AUC24h/MIC) was 448.45 (325.89-855.07). Vancomycin exposure was significantly higher in ascites than in bile (11.67 ± 3.60 vs 4.31 ± 2.11 mg/L; P < .0001). Penetration rates were 65.99% ± 26.90% in ascites and 18.50% ± 9.48% in bile (P < .0001). Compared with serum-only TDM, dual-TDM was associated with higher clinical efficacy (88.00% vs 57.14%; P = .047) and microbiological efficacy (92.00% vs 57.14%; P = .016), without increased adverse events.
Conclusion:
Vancomycin demonstrates adequate penetration into ascitic fluid but markedly limited penetration into bile. In this exploratory cohort, dual-TDM was associated with higher target attainment and apparent clinical benefit, but allocation was non-random and the analysis was under-powered; site-specific TDM, alongside consideration of alternative anti-Gram-positive agents for biliary infections, warrants confirmation in adequately powered randomized trials.
Related Concept Videos
Estimation of k and VD of Aminoglycosides
Dosage Interval and Administration Route: Determination Methods
Determination of Multiple Dosing Parameters: Steady-State, Minimum and Maximum Concentrations
Drug Accumulation During Multiple Dosing: Intermittent IV Infusions
Clearance Models: Compartment Models
Pharmaceutical Alternatives: Stability-Related Therapeutic Nonequivalence
