American College of Gastroenterology Issues Guidelines for Treatment of Helicobacter pylori Infection

August 21, 2007 — The American College of Gastroenterology (ACG) has issued guidelines for treatment of Helicobacter pylori infection and published them in the August issue of the American Journal of Gastroenterology.
"Helicobacter pylori (H. pylori) remains one of the most common worldwide human infections and is associated with a number of important upper gastrointestinal (GI) conditions including chronic gastritis, peptic ulcer disease (PUD), and gastric malignancy," write William D. Chey, MD, FACG, AGAF, FACP, from the University of Michigan Medical Center in Ann Arbor, Michigan, and Benjamin C.Y. Wong, MD, PhD, FACG, FACP, from the University of Hong Kong, and colleagues from the Practice Parameters Committee of the ACG. "The prevalence of H. pylori is closely tied to socioeconomic conditions and accordingly, this infection is more common in developing countries than in developed countries such as the United States. Regardless, it has been estimated that 30 - 40% of the U.S. population is infected with H. pylori."
Since the ACG last published guidelines for the management of H pylori infection in 1998, considerable new evidence has become available regarding diagnosis and treatment. Therefore, the Practice Parameters Committee and Governing Board of the ACG issued this updated management guideline to facilitate clinical management of patients with H pylori infection.
The investigators searched Medline, PubMed, and the Cochrane Database for available evidence underlying these guidelines, which include summary recommendations and more detailed descriptions of supporting evidence and rationale.
Endoscopic or nonendoscopic methods can be used to diagnose H pylori. Choice of diagnostic workup in a specific patient should consider the need for endoscopy, pretest probability of infection, local availability of testing methods, and test performance characteristics and costs.
For populations with a low pretest probability of H pylori infection, the nonendoscopic urea breath and fecal antigen tests have a better positive predictive value than do antibody tests. Antibody testing identifies an immunologic reaction to the infection, whereas the urease tests and fecal antigen test identify the presence of active H pylori infection.
Established indications for eradication of H pylori include PUD, gastric mucosa-associated lymphoid tissue (MALT) lymphoma, and uninvestigated dyspepsia.
There is still controversy regarding whether to test for H pylori in the presence of functional dyspepsia, gastroesophageal reflux disease (GERD), nonsteroidal anti-inflammatory drug (NSAID) use, iron-deficiency anemia, or risk factors for developing gastric cancer. However, a subset of patients with functional dyspepsia benefit from H pylori eradication, and recent evidence suggests a link between H pylori infection and unexplained iron-deficiency anemia.
To confirm eradication of H pylori infection, testing should be performed in patients with PUD who were treated for H pylori, those with persistent dyspeptic symptoms following the test-and-treat strategy, those with H pylori-associated MALT lymphoma, and those who are status post resection of early gastric cancer.
Accepted first-line treatments for H pylori are a 10- to 14-day course of proton pump inhibitor (PPI), clarithromycin, and amoxicillin or metronidazole; or of PPI, bismuth, tetracycline, and metronidazole.
In part because of increasing H pylori resistance to clarithromycin, rates of eradication for first-line treatment with a PPI, clarithromycin, and amoxicillin have decreased to 70% to 85% worldwide. Seven-day regimens may have lower eradication rates than 14-day regimens.
"The most important predictors of treatment failure following anti-H. pylori therapy include poor compliance and antibiotic resistance," the study authors write. "It is critical for clinicians to stress the importance of taking the medications as prescribed to minimize the likelihood of treatment failure and development of antibiotic resistance.... There is limited evidence to suggest that smoking, alcohol consumption, and diet may also adversely affect the likelihood of successful eradication."
Another therapeutic option for first-line treatment is a 7- to 14-day course of bismuth-containing quadruple regimens. Although sequential therapy for 10 days has appeared promising in European trials, this regimen has not yet been validated in North America and therefore cannot yet be recommended as a standard first-line treatment. Sequential treatment consists of a 5-day course of a PPI and amoxicillin, followed by an additional 5 days of a PPI, clarithromycin, and tinidazole.
Bismuth quadruple therapy is the most widely used salvage regimen for persistent H pylori infection. Evidence from recent trials suggest that combination therapy with a PPI, levofloxacin, and amoxicillin for 10 days is more effective and better tolerated than is bismuth quadruple therapy for treatment of patients with persistent infection, but this has not yet been validated in the United States.
Several recent trials studies have compared alternatives with bismuth-based quadruple salvage therapy, such as rifabutin, with rates of eradication ranging from 38% to 91%; furazolidone, with rates of eradication ranging from 52% to 90%; and levofloxacin-based triple therapy.
"Whether levofloxacin resistance is absolute as is the case with clarithromycin or more relative as with metronidazole remains to be determined as well," the study authors conclude. "While awaiting data on antimicrobial resistance and efficacy from the United States, given the shortage of effective, validated salvage regimens, it seems reasonable to consider levofloxacin-based triple therapy in circumstances where bismuth or clarithromycin-based therapies are not an option."
Am J Gastroenterol. 2007;102:1808-1825.