The emergence of Enterococcus faecium resistant to glycopeptides and other standard agents--a preliminary report.

We describe the emergence of vancomycin-resistant (VmR) Enterococcus faecium on a liver unit. Over a 22 month period, 110 patients acquired VmR E. faecium. Ribotyping identified 116 patient isolates. Five ribotypes accounted for 78% of patient isolates, the maximum number of patient isolates of a single ribotype was 37, and five clusters of four ribotypes were found. Seven patients acquired more than one ribotype. Environmental sampling yielded VmR E. faecium of the same ribotype as concurrent patient isolates. Clinical specimens from 38 liver transplant patients yielded VmR E. faecium and these were compared to 29 who acquired vancomycin-sensitive (VmS) E. faecium. Logistic regression analysis indicated that duration of admission was the only independent risk factor for acquisition of VmR E. faecium.