Cj. Donskey et al., Effect of antibiotic therapy on the density of vancomycin-resistant enterococci in the stool of colonized patients., N ENG J MED, 343(26), 2000, pp. 1925-1932
Citations number
38
Categorie Soggetti
General & Internal Medicine","Medical Research General Topics
Background: Colonization and infection with vancomycin-resistant enterococc
i have been associated with exposure to antibiotics that are active against
anaerobes. In mice that have intestinal colonization with vancomycin-resis
tant enterococci, these agents promote high-density colonization, whereas a
ntibiotics with minimal antianaerobic activity do not.
Methods: We conducted a seven-month prospective study of 51 patients who we
re colonized with vancomycin-resistant enterococci, as evidenced by the pre
sence of the bacteria in stool. We examined the density of vancomycin-resis
tant enterococci in stool during and after therapy with antibiotic regimens
and compared the effect on this density of antianaerobic agents and agents
with minimal antianaerobic activity. In a subgroup of 10 patients, culture
s of environmental specimens (e.g., from bedding and clothing) were obtaine
d.
Results: During treatment with 40 of 42 antianaerobic-antibiotic regimens (
95 percent), high-density colonization with vancomycin-resistant enterococc
i was maintained (mean [+/-SD] number of organisms, 7.8+/-1.5 log per gram
of stool). The density of colonization decreased after these regimens were
discontinued. Among patients who had not received antianaerobic antibiotics
for at least one week, 10 of 13 patients who began such regimens had an in
crease in the number of organisms of more than 1.0 log per gram (mean incre
ase, 2.2 log per gram), whereas among 10 patients who began regimens of ant
ibiotics with minimal antianaerobic activity, there was a mean decrease in
the number of enterococci of 0.6 log per gram (P=0.006 for the difference b
etween groups). When the density of vancomycin-resistant enterococci in sto
ol was at least 4 log per gram, 10 of 12 sets of cultures of environmental
specimens had at least one positive sample, as compared with 1 of 9 sets fr
om patients with a mean number of organisms in stool of less than 4 log per
gram (P=0.002).
Conclusions: For patients with vancomycin-resistant enterococci in stool, t
reatment with antianaerobic antibiotics promotes high-density colonization.
Limiting the use of such agents in these patients may help decrease the sp
read of vancomycin-resistant enterococci. (N Engl J Med 2000;343:1925-32.)
(C) 2000, Massachusetts Medical Society.