Vancomycin: a dura damaging friend of the spine surgeon? An experimental study

PURPOSE: The aim of this experimental study was to better understand the impact of locally applied vancomycin on the dura mater. METHODS: Spinal dura mater was extracted from cattle, sheep, and red deer and trimmed for the subsequent experimental purposes. Three different vancomycin concentrations of 1 mg/mL, 10 mg/mL, and 100 mg/mL were applied in a semi-open, self-constructed diffusion chamber. Protein quantitation and electrophoresis were performed to monitor proteins in the dura perfusates at different time points. High resolution liquid-chromatography mass spectrometry was performed for the measurement of time-dependent relative mass transfer of vancomycin at different time points. RESULTS: While previous results for a diffusion unlimited scenario utilizing second-harmonic generation microscopy (SHG) on dura mater thin sections showed concentration-dependent changes manifesting as tissue section swelling over time and a loss in SHG intensity (Schultz et al. (2025), Anal Chem acs.analchem.4c04887. https://doi.org/10.1021/acs.analchem.4c04887 ), our recent results on bulk tissue now revealed that vancomycin induced elevated protein loss. Specifically, protein release at a dosage of 10 mg/mL was notably higher than that in the cryo-control group (2-10 min). Our results showed that the relative mass transfer of vancomycin was greater (mean 3.9%) for the 1 mg/mL vancomycin experiment and the 10 mg/mL vancomycin experiment (mean 4.8%) compared to the 100 mg/mL vancomycin experiment (0.69%). CONCLUSION: Through biochemical analysis, our research provides novel perspectives on how different concentrations of vancomycin impact the dura mater. Our study demonstrates that vancomycin damages the dura by protein release and swelling.