Rational Helicobacter pylori Therapy
Generally, clinicians should have 2 preferred first-line regimens known to be effective locally, with the choice between them based on the patients history of prior drug use and exposure (Figure 2). The regimen with the highest predicted successful outcome always should be used first. Treatment success always should be confirmed, generally using a noninvasive test for active infection such as the stool antigen or urea breath test. Confirmation of cure also provides the clinician with an early warning of the development of increasing resistance in the community.
(Enlarge Image)
Figure 2.
Example of choices of clarithromycin-containing regimens for an individual patient based on predicted resistance to clarithomycin and metronidazole.
H pylori is naturally resistant to many antimicrobials and rapidly has become resistant to others. The use of agents to which the organism is resistant either naturally or by acquired resistance has no effect on the outcome of therapy with agents to which the strain is susceptible. Prior use of an antibiotic for another infection often results in the H pylori becoming resistant (a bystander effect), and clarithromycin and other macrolides, fluoroquinolones, and rifabutin should not be used again. Generally, amoxicillin and tetracycline can be re-used because resistance rarely develops. The key outcome variable is whether the infecting strain is susceptible. In our experience, the same high success rates are obtained with the first and the nth-line regimen, provided the organisms are susceptible and good compliance is obtained. To the infection, all attempts with agents to which it is susceptible are first attempts. We do not know whether some patients may be more difficult to cure than others but, all things being equal, the effectiveness of first-line agents, first-line alternative agents, or even salvage therapies is similar if the organisms are susceptible. Repeated failures should prompt assessment of compliance and rare events such as the development of amoxicillin resistance.
Second or Subsequent Treatments for Treatment Failures
Generally, clinicians should have 2 preferred first-line regimens known to be effective locally, with the choice between them based on the patients history of prior drug use and exposure (Figure 2). The regimen with the highest predicted successful outcome always should be used first. Treatment success always should be confirmed, generally using a noninvasive test for active infection such as the stool antigen or urea breath test. Confirmation of cure also provides the clinician with an early warning of the development of increasing resistance in the community.
(Enlarge Image)
Figure 2.
Example of choices of clarithromycin-containing regimens for an individual patient based on predicted resistance to clarithomycin and metronidazole.
H pylori is naturally resistant to many antimicrobials and rapidly has become resistant to others. The use of agents to which the organism is resistant either naturally or by acquired resistance has no effect on the outcome of therapy with agents to which the strain is susceptible. Prior use of an antibiotic for another infection often results in the H pylori becoming resistant (a bystander effect), and clarithromycin and other macrolides, fluoroquinolones, and rifabutin should not be used again. Generally, amoxicillin and tetracycline can be re-used because resistance rarely develops. The key outcome variable is whether the infecting strain is susceptible. In our experience, the same high success rates are obtained with the first and the nth-line regimen, provided the organisms are susceptible and good compliance is obtained. To the infection, all attempts with agents to which it is susceptible are first attempts. We do not know whether some patients may be more difficult to cure than others but, all things being equal, the effectiveness of first-line agents, first-line alternative agents, or even salvage therapies is similar if the organisms are susceptible. Repeated failures should prompt assessment of compliance and rare events such as the development of amoxicillin resistance.
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