VANCOMYCIN-RESISTANT ENTEROCOCCI IN STOOL SPECIMENS SUBMITTED FOR CLOSTRIDIUM-DIFFICILE CYTOTOXIN ASSAY

The prevalence of, and clinical risk factors associated with, vancomyc in-resistant enterococcal colonization were investigated in patients s uspected of having Clostridium difficile infection. Stools submitted f or C difficile cytotoxin testing were screened for vancomycin-resistan t enterococci (VRE). Isolates were speciated and characterized further by antibiotic susceptibility testing, DNA fingerprinting, and DNA:DNA hybridization for detection of specific vancomycin resistance genes. Bf the 79 evaluable patients identified during a 3-month period, 16.5% were VRE-positive. The VRE isolates were genetically heterogeneous, a lthough all carried the vanA gene. DNA finger-printing data suggest th at patient-to-patient transmission occurred, implicating colonized pat ients as potential reservoirs for VRE transmission. A positive C diffi cile cytotoxin assay and diabetes mellitus were the only identifiable risk factors associated with VRE colonization. Patients at risk for C difficile infection therefore may serve as reservoirs for VRE.