title: Effect of vancomycin on intestinal flora of patients who previously received antimicrobial therapy.
abstract: To evaluate the ecological disturbances of peroral vancomycin administration following cephalosporin administration, 20 healthy volunteers received cefuroxime axetil tablets (250 mg) perorally twice a day for 1 week, and 10 of these volunteers subsequently received vancomycin capsules (125 mg) perorally four times daily for 7 days. The concentration of vancomycin in feces after 1 week of vancomycin administration was high (mean +/- SD, 520 +/- 197 mg/kg), which correlated with the ecological disturbances noted in the vancomycin recipients. Vancomycin administration resulted in a rapid decrease in the numbers of intestinal Enterococcus faecium, Enterococcus faecalis, and Enterococcus durans (P < or = .05), while there was a significant emergence of motile enterococci with decreased susceptibility to vancomycin (Enterococcus gallinarum and Enterococcus casseliflavus; minimum inhibitory concentration, 4-16 mg/L) (P < or = .01). Because of vancomycin administration, there was also a significant overgrowth of vancomycin-resistant Pediococcus species and lactobacilli as well as of Klebsiella species, Citrobacter species, and Enterobacter species (P < or = .01). The numbers of bifidobacteria and Bacteroides species were significantly reduced during vancomycin administration. None of the enterococcal strains carried vanA or vanB. Twenty-two of the 27 motile enterococci carried the vanC-1 gene specific for E. gallinarum, whereas five strains carried the vanC-2(C-3) gene, thus implicating that they were E. casseliflavus or Enterococcus flavescens.
authors.affiliation: Department of Immunology, Karolinska Institute, Huddinge University Hospital, Sweden.
authors.forename: C
authors.initials: C
authors.lastname: Edlund
authors.forename: L
authors.initials: L
authors.lastname: Barkholt
authors.forename: B
authors.initials: B
authors.lastname: Olsson-Liljequist
authors.forename: C E
authors.initials: CE
authors.lastname: Nord
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000009:adverse effects* / Q000493:pharmacokinetics; D002444:Cefuroxime / Q000009:adverse effects / Q000031:analogs & derivatives; D002511:Cephalosporins / Q000009:adverse effects; D015169:Colony Count, Microbial; D004352:Drug Resistance, Microbial / Q000235:genetics; D017753:Ecosystem; D016983:Enterococcus / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D005243:Feces / Q000737:chemistry / Q000382:microbiology; D005260:Female; D005838:Genotype; D006095:Gram-Positive Cocci / Q000187:drug effects / Q000302:isolation & purification; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000187:drug effects* / Q000382:microbiology*; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D014640:Vancomycin / Q000008:administration & dosage / Q000009:adverse effects* / Q000493:pharmacokinetics
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D014640:Vancomycin; D002444:Cefuroxime; C040738:cefuroxime axetil