Enteroaggregative Escherichia coli diarrhea in travelers: response to rifaximin therapy.
OBJECTIVE
We have recently shown that enteroaggregative Escherichia coli (EAEC) strains commonly cause travelers' diarrhea. The study was designed to determine whether U.S. travelers with EAEC diarrhea responded to rifaximin therapy.


METHODS
In a multicenter placebo-controlled clinical trial of travelers' diarrhea without non-EAEC pathogens we evaluated 2 doses of rifaximin. EAEC was sought in stool samples in enrolled subjects by HEp-2 cell assay. Response to rifaximin (both groups combined) and placebo were evaluated in EAEC-positive and EAEC-negative patient groups.


RESULTS
Compared with placebo, rifaximin shortened the postenrollment illness in travelers with EAEC diarrhea (median, 22 vs. 72 hours; P = 0.03). In subjects with EAEC-negative diarrhea, the median duration of post-treatment diarrhea was shorter with rifaximin (33 hours) than with placebo (52 hours), but this difference was not significantly different (P = 0.14).


CONCLUSIONS
Improvement of EAEC-mediated diarrhea with antibiotic treatment supports the pathogenicity of this organism in travelers to developing countries. The study provides information on the value of the poorly absorbed drug rifaximin in therapy of travelers' diarrhea.
Infante
Rosa M
RM
Center for Infectious Diseases, The University of Texas-Houston School of Public Health and Medical School, Houston, Texas, USA.
Ericsson
Charles D
CD
Jiang
Zhi-Dong
ZD
Ke
Shi
S
Steffen
Robert
R
Riopel
Lise
L
Sack
David A
DA
DuPont
Herbert L
HL
D000890:Anti-Infective Agents / Q000627:therapeutic use*; D003967:Diarrhea / Q000188:drug therapy* / Q000382:microbiology; D004926:Escherichia coli / Q000302:isolation & purification* / Q000472:pathogenicity; D004927:Escherichia coli Infections / Q000175:diagnosis / Q000188:drug therapy* / Q000382:microbiology; D006801:Humans; D012294:Rifamycins / Q000627:therapeutic use*; D000078262:Rifaximin; D014195:Travel; D016896:Treatment Outcome
D000890:Anti-Infective Agents; D012294:Rifamycins; D000078262:Rifaximin