Current Consensus and Remaining Questions Regarding the Diagnosis and Treatment of Helicobacter pylori Infection.

The first key point in Kenneth E. L. McColl’s article in The New England Journal of Medicine regards the clear indications for eradicating Helicobacter pylori infection.1 As McColl notes, there is general agreement in this area between the European guidelines, published in the Maastricht III Consensus Report, and the US guidelines, published by the American College of Gastroenterology.1–3 Both guidelines recommend H. pylori eradication in the following groups. Numerous studies have clearly demonstrated that eradication of H. pylori infection is beneficial in patients with gastric or duodenal ulcers, both in terms of facilitating ulcer healing and, more importantly, in terms of preventing ulcer recurrence. One recent study that supports this conclusion is a multicenter, collaborative, follow-up study of 1,000 patients with H. pylori-related peptic ulcer bleeding.4 All of the patients in this study underwent eradication therapy for H. pylori infection, and eradication was confirmed by appropriate follow-up testing. Sixty-nine percent of these patients had a duodenal ulcer, 27% had a gastric ulcer, and 4% had a pyloric ulcer. Over 2 years of follow-up, only 5 patients experienced ulcer rebleeding following H. pylori eradication, for a rebleeding incidence of only 0.15% per patient-year of follow-up. This study shows that H. pylori eradication alters the natural history of peptic ulcer disease and peptic ulcer—related complications such as bleeding. Another group of patients who clearly benefit from eradication of H. pylori infection are those with mucosa-asso-ciated lymphoid tissue (MALT) lymphomas of the stomach. H. pylori infection has been closely linked to the pathogenesis of this type of neoplasm, and eradication of H. pylori has revolutionized the treatment of these lesions. In the past, MALT lymphomas were treated with radiation or chemotherapy, but treatment now focuses primarily on eradicating H. pylori infection. Among patients with low-grade MALT lymphomas, a substantial proportion of patients—upward of 70—80%—will achieve complete remission following eradication of H. pylori infection, and some preliminary data suggest that a subset of patients with high-grade MALT lymphomas might also benefit from eradication of H. pylori infection. A third group that should receive H. pylori eradication therapy includes patients who have undergone endoscopic resection of early gastric cancer. Several studies from the Far East have shown that eradication of H. pylori infection in this population markedly diminishes the likelihood of gastric cancer recurrence. Functional dyspepsia is perhaps the most common indication for H. pylori eradication in developed countries and possibly worldwide. This term describes patients who have unexplained upper abdominal pain or discomfort and normal findings on upper endoscopy. Data suggest that eradicating H. pylori in patients with functional dyspepsia offers a small but statistically significant benefit compared to either a short course of proton pump inhibitor (PPI) therapy or placebo. One possible explanation for the benefits of H. pylori eradication is that some patients with functional dyspepsia actually have peptic ulcer disease that was missed or inactive at the time of their upper endoscopy. Alternatively, it is possible that the improvements in gastritis that accompany eradication of H. pylori infection might lead to symptom-related benefits even in the absence of peptic ulcer disease. While the benefits of H. pylori eradication in the aforementioned groups are well recognized, treatment of other groups remains controversial. For example, some interesting data suggest that idiopathic thrombocytopenic purpura may resolve in some individuals after eradication of H. pylori infection, but more data are needed to confirm this benefit. Another very controversial area is the potential role of H. pylori infection as a cause of unexplained iron-deficiency anemia, but the data in this area are inconclusive. Finally, the McColl article states that H. pylori infection does not play a role in gastroesopha-geal reflux disease (GERD), but this remains a confusing topic.1 Some data suggest that a subset of patients with GERD symptoms may improve after eradication of H. pylori infection, while other studies suggest that some individuals with GERD symptoms may actually worsen after eradication of H. pylori infection. Most often, H. pylori eradication leads to no significant change in GERD symptoms. Whether patients with GERD symptoms improve, worsen, or stay the same following eradication of H. pylori infection probably depends to a large extent on the type of gastritis caused by the infection and its attendant effects on gastric acid secretion.