Natural history of vancomycin-resistant enterococcal colonization in liverand kidney transplant recipients

At Mayo Medical Center (Rochester, MN), surveillance rectal (and other-site ) cultures have been routinely collected from liver transplant recipients a s part of a selective bowel decontamination program. Beginning in 1995, van comycin-resistant enterococcus (VRE) colonization and infection were identi fied in Mayo Clinic liver and kidney transplant patients through our survei llance cultures. The purpose of this study is to describe the natural histo ry of VRE colonization in this patient population. Fifty-two patients with VRE colonization (predominantly with a single vanB clone) were identified f rom September 1995 through December 1997. Five hundred ninety cultures were reviewed for this study (mean, 11.3 cultures/patient). The median time fro m initial VRE colonization to the last surveillance culture obtained was 30 6 days (range, 1 to 1,393 days). VRE infection was documented in 6 patients (11.3%). Eighteen patients (35%) met the criteria for clearance of VRE col onization, defined as VRE-negative rectal culture results on at least 3 con secutive occasions greater than 1 week apart. However, VRE was detected on subsequent surveillance cultures from 2 of these patients (11% relapse rate ). Of the remaining 34 patients, 16 remained colonized with VRE and 18 did not meet the definition for clearance of VRE colonization because of incomp lete follow-up. This study documents that VRE colonization usually persists for months to years in liver and kidney transplant patients.