INFLUENCE OF ORAL GLYCOPEPTIDES ON THE FECAL FLORA OF HUMAN VOLUNTEERS - SELECTION OF HIGHLY GLYCOPEPTIDE-RESISTANT ENTEROCOCCI

Changes in fecal flora were evaluated in 22 healthy volunteers adminis tered oral vancomycin or teicoplanin in 1989-1991 in Belgium, Evaluati on of 5 colonies per subject revealed no glycopeptide-resistant entero cocci in the predominant flora before glycopeptide administration; how ever, large numbers (mostly Enterococcus faecium) emerged by the end o f the study in 14 (64%) of the subjects, Pediococci and lactobacilli a lso increased in number, In 1992, 40 healthy volunteers and 33 cancer patients were evaluated by plating stool samples directly onto selecti ve media containing vancomycin; low numbers of vancomycin-resistant en terococci (<50 cfu/g) were found in 11 (28%) of the 40 and 4 (12%) of the 33 samples, respectively, DNA restriction fragment length polymorp hism analysis showed that most isolates were different, but all contai ned vanA in Tn1546-like elements, These results indicate that vanA and Tn1546-like elements were common in Belgium as early as 1989 and that community-based individuals in that location likely form a major rese rvoir for glycopeptide-resistant enterococci.