Evidence for Biliary Excretion of Vancomycin into Stool during Intravenous Therapy: Potential Implications for Rectal Colonization with Vancomycin-Resistant Enterococci

Sixty-three stool samples and five bile samples were prospectively collected from 33 patients receiving intravenous vancomycin therapy and were quantitatively analyzed for vancomycin by a competitive immunoassay. Vancomycin was excreted via bile into the stools of almost all patients at concentrations of 3.3 to 94.8 microg/ml after >/=5 days of a therapy of 1 g every 12 h.