Previous Article | Next Article ![]()
Antimicrobial Agents and Chemotherapy, October 2000, p. 2623-2629, Vol. 44, No. 10
Unité de Pathogénie
Bactérienne des Muqueuses, Institut Pasteur, 75724 Paris Cedex
15,1 and Service de
Bactériologie-Virologie, Hôpital Henri Mondor,
Creteil,3 France, and Department of
Medical Microbiology, Royal Free and University College Medical
School, London, United Kingdom2
Received 7 February 2000/Returned for modification 1 June
2000/Accepted 27 June 2000
The main objectives of this study were to determine whether the
nitroreductase enzyme encoded by the rdxA gene of
Helicobacter pylori was responsible for reductive
activation of nitrofurantoin and whether a triple-therapy regimen with
nitrofurantoin was able to eradicate metronidazole-sensitive and
-resistant H. pylori infections from mice. The
susceptibilities to nitrofurantoin of parent and isogenic
rdxA mutant strains (three pairs), as well as a series of
matched metronidazole-sensitive and -resistant strains isolated from
mice (30) and patients (20), were assessed by
agar dilution determination of the MIC. Groups of mice colonized with
the metronidazole-sensitive H. pylori SS1 strain or a
metronidazole-resistant rdxA SS1 mutant were treated with
either metronidazole or nitrofurantoin as part of a triple-therapy
regimen. One month after the completion of treatment the mice were
sacrificed and their stomachs were cultured for H. pylori.
The nitrofurantoin MICs for all strains tested were between 0.5 and 4.0 µg/ml. There was no significant difference between the susceptibility
to nitrofurantoin of the parental strains and those of respective
rdxA mutants or between those of matched
metronidazole-sensitive and -resistant H. pylori isolates.
The regimen with metronidazole eradicated infection from all eight
SS1-infected mice and from one of eight mice inoculated with the
rdxA mutant (P
0066-4804/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.
Evaluation of Nitrofurantoin Combination Therapy of
Metronidazole-Sensitive and -Resistant Helicobacter pylori
Infections in Mice
0.001). The regimen with
nitrofurantoin failed to eradicate infection from any of the six
SS1-infected mice (P
0.001) and cleared infection
from one of seven mice inoculated with the rdxA mutant.
These results demonstrate that, despite the good in vitro activity of
nitrofurantoin against H. pylori and the lack of
cross-resistance between metronidazole and nitrofurantoin, eradication
regimens involving nitrofurantoin are unable to eradicate either
metronidazole-sensitive or -resistant H. pylori infections
from mice.
*
Corresponding author. Mailing address: Department of
Medical Microbiology, Royal Free and University College Medical School, Royal Free Campus, Rowland Hill St., London NW3 2PF, United
Kingdom. Phone: 44-20-77940500, ext. 4111. Fax: 44-20-77940433. E-mail: pjenks2{at}hotmail.com.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»