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

Abstract

T he natural history of vancomycin-resistant enterococcus (VRE) infection is such that VRE colonization, predominantly of the gastrointestinal tract, typically precedes infection. At Mayo Medical Center (Rochester, MN), routine aerobic bacterial throat, rectal, wound, biliary, and urinary surveillance cultures have been collected from liver transplant recipients as part of a selective bowel antibiotic decontamination program for liver transplant patients. Beginning in 1995, as a result of these surveillance cultures, VRE colonization was identified in liver and kidney transplant patients. The purpose of this study is to describe the natural history of VRE colonization in liver and kidney transplant patients. Methods Cultures for VRERoutine surveillance aerobic bacterial throat, rectal, wound, biliary, and urinary cultures have been collected from hospitalized liver transplant recipients as part of a selective bowel decontamination program for liver transplant patients since the inception of the liver transplant program at Mayo Medical Center in 1985. Surveillance cultures were originally obtained twice weekly for 1 week posttransplantation and then weekly until selective bowel decontamination was discontinued (ϳ3 weeks). Through these surveillance cultures, VRE colonization was detected in the liver transplant population.Beginning November 1995, admission and twice-weekly rectal surveillance cultures were collected from all patients admitted to the adult liver, kidney, and kidney/pancreas transplant unit. These specimens were cultured on primary sheep blood agar or subculture of enriched brain heart infusion broth to Columbia colistin-nalidixic acid (CNA) agar. Subsequent to the identification of the first patient with VRE colonization, some of these cultures were ordered as "VRE screens" and cultured on selective media, as follows. Beginning October 1995, in-house CNA agar with 16 g/mL of vancomycin was used. In June 1996, Enterococcosel agar with 8 g/mL of vancomycin (Becton Dickinson, Cockeysville, MD) was substituted. The study period extended from 1985 through December 1997. Selective Bowel DecontaminationSelective bowel decontamination was performed using a mixture of 80 mg of gentamicin, 100 mg of polymyxin E, and 2 million U of nystatin administered orally or by nasogastric tube 4 times daily, beginning at least 2 days before liver transplantation and discontinued at the time of discharge from the initial hospitalization. This regimen was resumed when patients were rehospitalized. Orabase paste (Colgate, Surgery, ‡Hepatology, and §Clinical Microbiology, Mayo Clinic and Foundation, Rochester, MN; and ʈCorixa Corporation, From the *Divisions of Infectious Diseases, †Transplantation

Incidence and clinical complications of vancomycin-resistant enterococcus in pediatric stem cell transplant patients

“…VRE has emerged as an important pathogen in liver, kidney, and SCT units in the United States. [4][5][6][7][8]20 Colonization with VRE has been reported in as many as 50% of pediatric oncology patients. 17 At present, there are very limited data with regard to the incidence and clinical consequences of VRE in pediatric SCT patients.…”

“…3 Immune compromised patients, especially adult liver, kidney, and pancreatic transplant patients, have experienced serious morbidity and mortality as a consequence of VRE. [4][5][6][7][8] The first reported case of VRE bacteremia in a bone marrow transplant recipient was described in 1991. 9 Recent reports in adult stem cell transplant (SCT) patients have shown that VRE bacteremia results in significant complications and fatalities.…”

Duration of Contact Precautions for Acute-Care Settings

“…Data on duration of VRE colonization indicate that colonization may be prolonged, with high rates of relapse after multiple consecutive negative surveillance cultures. [14][15][16] Factors associated with prolonged VRE carriage include immunocompromising conditions and concomitant antibiotic exposure. [16][17][18][19] Additionally, patients with diarrhea and uncontrolled respiratory secretions and draining wounds may pose the highest risk for transmission in the healthcare environment.…”

“…12,60 Some studies have included surveillance cultures obtained from other sites including throat and urine samples. 16 While limited, data comparing the sensitivity of rectal and perirectal cultures suggest that both are comparable. 74 …”

“…14-16 Factors associated with prolonged VRE carriage include immunocompromising conditions and concomitant antibiotic exposure. [16][17][18][19] Additionally, patients with diarrhea and uncontrolled respiratory secretions and draining wounds may pose the highest risk for transmission in the healthcare environment. The sensitivity of surveillance cultures of stool or rectal swab samples for the detecting VRE colonization is not well established.…”