AN ESTIMATED 30% to 40%

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1 Helicobacter pylori Related Disease Guidelines for Testing and Treatment ORIGINAL INVESTIGATION Walter L. Peterson, MD; A. Mark Fendrick, MD; David R. Cave, MD, PhD; David A. Peura, MD; Susan M. Garabedian-Ruffalo, PharmD; Loren Laine, MD Objective: To develop practical guidelines for the treatment of patients with suspected and documented Helicobacter pylori related gastroduodenal diseases. Methods: A panel of physicians with expertise in H pylori reviewed, critically appraised, and synthesized the literature on assigned topics and presented their overviews to the panel. Consensus was obtained in controversial areas through discussion. Results and Conclusions: The panel recommended testing for H pylori in patients with active ulcers, a history of ulcers, or gastric mucosa-associated lymphoid tissue lymphomas. Young, otherwise healthy patients with ulcerlike dyspepsia and those with a family history or fear of gastric cancer may also undergo H pylori testing. Nonendoscopic methods are preferred for H pylori diagnosis. Dual medication regimens should not be used for therapy; twice-daily triple therapy with a proton pump inhibitor or ranitidine bismuth citrate, clarithromycin, and amoxicillin for 10 to 14 days is an appropriate therapy. Posttreatment assessment of H pylori status using urea breath testing should be considered in patients with a documented history of ulcer disease or with persistent symptoms. Arch Intern Med. 2000;160: From the Medical Service, Dallas VA Medical Center, and the Department of Medicine, University of Texas Southwestern Medical School at Dallas (Dr Peterson); the Departments of Internal Medicine and Health Management and Policy, University of Michigan, Ann Arbor (Dr Fendrick); the Department of Medicine, Tufts University Medical School, Boston, Mass (Dr Cave); Department of Medicine, University of Virginia, Charlottesville (Dr Peura); and the Department of Clinical Pharmacy Practice (Dr Garabedian-Ruffalo) and the School of Medicine, Department of Medicine (Dr Laine), University of Southern California, Los Angeles. AN ESTIMATED 30% to 40% of the US population is infected with Helicobacter pylori. 1 Infection with this spiral, urease-producing organism causes histological gastritis in all those infected, is the major cause of peptic ulcer disease, and is an important risk factor for the development of gastric adenocarcinoma and lymphoma. 2,3 Helicobacter pylori gastritis is found in up to 95% of patients with duodenal ulcers and 80% of patients with gastric ulcers in some parts of the world. 4 In the United States, the percentage is closer to 75%, perhaps reflecting a larger role for nonsteroidal anti-inflammatory drug induced ulcer disease. 5 In individuals with H pylori infection, the estimated lifetime risk for peptic ulcer disease is approximately 15%. 4,6 Infection with H pylori increases the risk for gastric adenocarcinoma up to 9-fold as determined by a meta-analysis of 3 nested case-control studies. 7-9 Given these findings, the International Agency for Research on Cancer 10 classified H pylori as a group 1 (a definite cause of cancer in humans) carcinogen. Helicobacter pylori related peptic ulcer disease significantly impacts patient quality of life and functional status. In a 1989 National Health Interview Survey 11 of individuals, up to 25% of those with a recent ulcer reported being in poor health, incapable of major activity, restricted in daily activity, unable to perform work, or confined to bed for more than 7 days during the previous 12 months. The overall economic impact of H pylori infection is staggering. It is estimated that the direct costs of treating H pylori related diseases and associated complications and lost productivity is $3.0 to $5.6 billion annually Studies 14,15 have documented that cure of H pylori infection in patients with peptic ulcers is associated with a reduction in ulcer recurrence and, in many patients, obviation of maintenance antisecretory therapy. In addition, cure of H pylori infection may produce regression or resolution of low-grade gastric mucosaassociated lymphoid tissue lymphomas. 16 Given the potential benefits of eradication of H pylori, a group of gastroenterologists 1285

2 and primary care physicians met to critically appraise and synthesize the current literature on H pylori infection to develop practical guidelines for diagnosis and treatment of patients with H pylori related diseases. WHO SHOULD BE TESTED FOR H PYLORI? Tests designed to detect H pylori should be performed only if the result will affect patient treatment. Specifically, H pylori diagnostic testing should be ordered only if a decision has been made to treat patients who have a positive result. The clinical superiority and cost benefits of H pylori testing of patients with newly diagnosed (by endoscopy or radiography) gastric or duodenal ulcer has been well studied. 12,17-19 Given the strong association between H pylori infection and ulcer disease, patients with a history of ulcer disease who are currently receiving maintenance antisecretory therapy should also be tested for H pylori infection. 20 In addition, decision and costbenefit analyses support nonendoscopic diagnostic testing of young, otherwise healthy patients with symptoms of ulcerlike dyspepsia Finally, patients with mucosa-associated lymphoid tissue lymphoma should be tested and treated. 7,10,24-30 The role of testing for H pylori infection in individuals receiving nonsteroidal antiinflammatory agents is controversial. Decision analyses 31,32 suggest that screening for H pylori to prevent gastric cancer may also be costeffective. In a study by Parsonnet and colleagues, 31 if H pylori eradication prevented only 30% of attributable cancers, screening the entire US population at age 50 years would cost $1 billion an amount similar to the estimated costs of colorectal screening and provide a costbenefit ratio of $ per year of life saved. If screening were performed in high-risk populations such as Japanese Americans, H pylori cure would only have to reduce the risk of gastric cancer by 5% to be costeffective at the benchmark of $ per year of life saved. Although these data are compelling, no controlled clinical trials have been performed and no study has documented that eradication of H pylori will decrease the risk of developing gastric cancer. 31 Therefore, routine population-based screening for H pylori cannot be recommended at this time. On the other hand, it is rational clinical behavior to screen individuals who come to a physician with a fear or strong family history of gastric adenocarcinoma. METHODS OF H PYLORI DETECTION Methods used to detect H pylori are typically referred to as endoscopic and nonendoscopic, with each having its advantages and disadvantages based on a patient s clinical history and current presentation. Endoscopic methods involve assessing several gastric biopsy samples for the presence of H pylori by histological examination, urease activity, or culture. 33 Of these assessment methods, histological examination is considered the reference standard. Use of special stains such as Giemsa or Genta stain may make identification of the organism easier on histological examination. 34 Assessment of the biopsy sample for urease activity (rapid urease test) is a highly sensitive (approximately 90%) and specific (approaching 100%) method of H pylori detection. 35 A limitation to the use of urease testing is in patients receiving proton pump inhibitors (PPIs) or highdose histamine 2 receptor antagonists (H2RAs), which might decrease H pylori density and consequently urease activity, thereby producing a false-negative result Culturing of H pylori is generally not used in establishing a primary diagnosis because of the potential for false-negative results due to errors in specimen acquisition, storage, or transportation and its timeconsuming nature (ie, requires up to 2 weeks for growth to occur). 41 The performance of culture is useful for the determination of antibiotic resistance, especially in patients who continue to be positive for H pylori after an initial treatment regimen. Helicobacter pylori detection by nonendoscopic methods such as blood antibody detection tests, urea breath tests (UBTs), and the recently approved assay for the detection of H pylori antigen in stool specimens 42 is indicated in clinical situations in which endoscopy is not indicated. Unlike blood antibody detection methods, UBT and fecal antigen detection denote active H pylori infection. Antibody tests to detect IgG antibodies to H pylori are less expensive and more convenient to use than UBTs but are somewhat less accurate Antibody tests can now be done in the office setting on fingerstick whole blood specimens, with results obtained within 10 minutes. Antibody testing is commonly used in the evaluation of dyspeptic patients before or in place of endoscopy. Because antibody titers often take many months to decrease after successful treatment and remain positive in many patients for years, blood antibody testing (eg, serologic testing) is less useful for the monitoring of posttreatment H pylori status. The UBT is a measure of current H pylori infection, relying on H pylori urease to hydrolyze urea labeled with radioactive carbon ( 13 Cor 14 C) and produce isotopically labeled carbon dioxide in the breath. As with biopsybased rapid urease tests, there is the potential for falsenegative UBT test results in individuals receiving antisecretory agents such as PPIs or high-dose H2RAs, antimicrobial agents, or bismuth-containing compounds, which reduce H pylori density ,46,47 Therefore, UBT should be avoided in those who have received bismuth or antibiotic drugs within the previous 4 weeks or antisecretory agents within the previous 2 weeks. Stool antigen testing has emerged as a rapid, nonendoscopic method of H pylori detection. A recently published study 42 found that stool antigen testing is highly sensitive and specific in the detection of H pylori in patients with dyspepsia and in those who have completed an H pylori eradication regimen. In the diagnosis of H pylori infection, the stool antigen detection method was highly sensitive (80%-100%) and comparable to that of the UBT (84%-100%). Stool antigen detection performed 4 weeks after completion of an H pylori eradication regimen had a sensitivity of 90%, a specificity of 95%, and a negative predictive value of 98%, rates that were comparable to those obtained with 13 C UBT. 42 Although 1286

3 the high rates of sensitivity and specificity with the stool antigen test in patients enrolled in the study by Vaira et al 42 are promising, several other investigators found a high rate of false-positive results in patients tested 4 weeks after completion of anti H pylori treatment CHOICE OF H PYLORI DETECTION METHOD BY CLINICAL SITUATION New-Onset Peptic Ulcer Patients with a newly established diagnosis of ulcer disease made by endoscopy or radiography should have as their initial diagnostic test a rapid urease test or a serum antibody test, respectively. If the results are positive, the patient should be treated with an effective H pylori eradication regimen (ie, antimicrobial agents plus an antisecretory agent). If the initial test results are negative, H pylori status should be confirmed by another test given the importance this knowledge will have on future therapy. In the case of an endoscopically documented ulcer, this confirmation could be by histological examination, blood antibody detection, UBT, or stool antigen test. In patients whose ulcer is found by radiographic means, a UBT or stool antigen test should be done to confirm the patient s H pylori status. In either scenario, if the confirmatory test result is also negative, the patient s ulcer should be treated in standard fashion (eg, with a PPI or H2RA) and other causes for ulcer disease should be considered. If the confirmatory test result is positive, suggesting that the initial test was falsely negative, the patient should be treated with an effective anti H pylori regimen. History of Peptic Ulcer Disease All patients who are currently receiving antisecretory agents, who have a history of uncomplicated ulcer disease documented by endoscopy or radiography, or who have a self-reported history of ulcer disease should be tested for H pylori infection using nonendoscopic detection methods. If the results are negative, use of the maintenance antisecretory drug can be discontinued if the sole indication for its use was history of peptic ulcer disease. H pylori status can be confirmed by a UBT at least 2 weeks after cessation of therapy or by stool antigen detection at least 4 weeks after therapy cessation in objectively diagnosed patients and on symptom recurrence in clinically diagnosed patients. The rationale for the difference in approach relates to a greater probability that patients with objectively diagnosed disease will be infected than will patients without such documentation. Dyspepsia Patients with new-onset dyspepsia who are 50 years and younger and who have no alarm symptoms suggestive of underlying malignancy (eg, bleeding, weight loss, anemia, or early satiety) should undergo H pylori antibody testing. Alternatively, these patients may be tested using the UBT or stool antigen detection. Patients undergoing H pylori testing by UBT should not have ingested PPIs or high-dose H2RAs within the previous 2 weeks or antimicrobial agents within the previous 4 weeks. If the test results are positive, these patients should be offered H pylori eradication therapy, the rationale being that some of these individuals will have active ulcer disease and benefit from therapy. A proportion of those who do not have an ulcer (ie, functional dyspepsia) may also benefit from eradication of H pylori and should also be at lower risk for development of gastric adenocarcinoma. Patients with new-onset dyspepsia who are older than 50 years or those of any age who have alarm symptoms should undergo upper endoscopy. If objective disease is found (ie, malignancy or ulcer disease) during endoscopy, H pylori infection should be detected by rapid urease testing of biopsy specimens. Patients who are positive for H pylori should have their infection treated within the context of the clinical diagnosis. If the rapid urease test results are negative, H pylori status can be confirmed using antibody testing or histological examination. Alternatively, a UBT can be used to confirm H pylori status. TREATMENT OF H PYLORI INFECTION Numerous regimens designed to cure H pylori infection have been evaluated and reported in the literature. Most regimens combine 1, 2, or 3 antibiotic agents (including bismuth compounds) with an antisecretory agent. Use of antisecretory agents combined with antimicrobial drugs increases the H pylori eradication rate (probably because an increase in the ph of the stomach increases the efficacy of some antimicrobial agents). 51,52 In addition, PPIs have been found 40 to have intrinsic in vitro inhibitory activity against H pylori. The use of antisecretory therapy also seems to hasten relief of ulcer symptoms. 53,54 No therapy is 100% effective for H pylori infection. However, several regimens have been devised that attain cure rates between 80% and 90%. These regimens consist of twice-daily triple therapy with a PPI or ranitidine bismuth citrate along with 2 antimicrobial agents such as clarithromycin and either amoxicillin or metronidazole Classic bismuth-based triple therapy (bismuth subsalicylate, metronidazole, and tetracycline all given 4 times a day) achieves eradication rates of approximately 80% in the United States 61 ; the eradication rate potentially can be increased by addition of a PPI. 62,63 The major concern regarding bismuth-based triple therapy relates to patient compliance because of the complexity of the regimen. Currently available dual therapies are not recommended for treatment of H pylori infection. Factors that significantly affect H pylori cure rate are patient compliance with the regimen, duration of therapy, and presence of antimicrobial resistance. Regardless of the regimen selected to treat H pylori infection, patients should be advised that full treatment compliance is necessary to maximize their potential for infection cure. Despite the results of numerous European studies 62,64,65 that suggest that 7 days of triple therapy is sufficient, clinical trials performed in the United States have found that the highest rates of cure are associated with treatment 1287

4 durations of 10 to 14 days. Therefore, we recommend that PPI or ranitidine bismuth citrate based triple therapy be administered for 10 to 14 days. Primary resistance to metronidazole therapy is common, 28% to 39% in the United States. 66 The rate of clarithromycin-resistant strains of H pylori is approximately 11%, and amoxicillin- or tetracycline-resistant strains have been reported only rarely However, after failed treatment with metronidazole or clarithromycin, resistance to these agents must be assumed if susceptibility testing is not available. FOLLOW-UP OF H PYLORI THERAPY Evaluation of patients after completion of H pylori therapy is helpful in determining the patient s future clinical course. Duodenal ulcers recurred in 6% of patients cured of infection compared with 67% of those who remained positive for H pylori. 70 Similar findings 70 were noted in patients with gastric ulcers: ulcer recurrence after treatment occurred in 4% of cured patients and 59% of those who continued to harbor H pylori. Patient symptoms after H pylori therapy do not always correlate with eradication success or failure. Relief of dyspepsia does not always suggest H pylori cure, although 2 studies 71,72 found that persistence of certain ulcerrelated symptoms (ie, nausea, epigastric discomfort, and ulcer pain) were predictive of continued infection. In one study, 72 symptoms or their absence were highly sensitive and specific for confirming eradication 6 months after treatment. However, the authors caution that symptom-based assessment should not be used to assess treatment outcome in high-risk patients. Conversely, continued symptoms do not always denote treatment failure. Therefore, follow-up and confirmatory testing might be useful in determining a patient s response to treatment and risk of ulcer recurrence. Nonendoscopic methods (eg, UBT) are recommended for confirming H pylori eradication after completion of therapy if such confirmation is deemed necessary. 58,73,74 A UBT should be performed no sooner than 4 to 6 weeks after completion of H pylori therapy. Use of PPIs or high-dose H2RAs should be discontinued for at least 2 weeks before administration of the UBT. 37 A recent study 42 found stool antigen detection to be a reliable method of confirmatory testing when performed 4 weeks after treatment. However, some studies have found a high rate of false-positive results using stool antigen detection 4 weeks after treatment. Antibody testing is less useful in the immediate evaluation of posttreatment response because high levels of antibodies to H pylori remain for variable and extended periods. 75 However, for an individual more than a year after therapy, seroconversion is a reliable indicator of successful eradication. 76 If endoscopy is clinically indicated (ie, to confirm ulcer healing) after treatment, the clinician should obtain multiple biopsy specimens from the gastric body and antrum for histological examination and urease testing to exclude persistent infection. Findings of a recent study 77 suggest that patients have a desire to know their H pylori status after completion of an H pylori eradication regimen. However, economic Diagnosis by Endoscopy Rapid Urease Test Confirm by Blood Antibody Testing (Histological Examination or Nonendoscopic Methods for Active Infection Can Be Used in Non Antisecretory Drug Users) Treat Ulcer With 4-6 wk of PPI or H2RA Patient With Confirmed Diagnosis of New Ulcer Treat H pylori With d of Twice Daily: Clarithromycin and Amoxicillin or Metronidazole Assess H pylori Status Using the UBT or Possibly Stool Antigen Detection Consider Other Causes of Ulcer Disease Diagnosis by Upper Gastrointestinal Tract Series Confirm H pylori Status Using Nonendoscopic Methods for Active Infection Treat Ulcer With 4-6 wk of PPI or H2RA Therapy Figure 1. Patients with a diagnosis of new ulcer. The diagnosis of Helicobacter pylori infection should be made using the rapid urease test in those undergoing endoscopy and blood antibody testing in those undergoing an upper gastrointestinal tract series. H pylori test results should be confirmed using nonendoscopic methods. Patients with positive H pylori test results should be treated with 10 to 14 days of a twice-daily regimen that includes a proton pump inhibitor (PPI) or ranitidine bismuth citrate (RBC), clarithromycin, and amoxicillin or metronidazole. Patients with ulcer who are negative for H pylori should be treated with 4 to 6 weeks of a PPI or a histamine 2 receptor antagonist (H2RA). *, Nonendoscopic methods for active infection include urea breath test (UBT) and stool antigen detection. The UBT should be performed only after use of antisecretory agents has been discontinued for at least 2 weeks and use of antimicrobial agents and bismuth has been discontinued for at least 4 weeks. Stool detection should be performed at least 4 weeks after H pylori eradiction therapy. Clinicians should keep in mind the potential for false-positive results with this test in patients who have completed a course of anti H pylori treatment., Patients who do not respond to a first course of therapy with a PPI or RBC, clarithromycin, and amoxicillin should be retreated with a PPI, metronidazole, bismuth subsalicylate, and tetracycline. Those who continue to have positive H pylori test results after 2 courses of anti H pylori treatment should be referred to a gastroenterologist., Patients with complicated ulcer disease who are positive for H pylori (by blood antibody testing or rapid urease test) should be treated for their infection followed by 6 weeks of antisecretory drug therapy. Cure of the infection should be assessed using the UBT 2 weeks after completion of the antisecretory agent therapy or by stool antigen testing. factors might limit the utility of performing confirmatory testing in all patients. Follow-up testing to confirm eradication should be performed routinely in all patients with a confirmed diagnosis of new ulcer disease or a documented history of complicated ulcer disease. Patients with a reported history of uncomplicated ulcer disease not documented by endoscopy or radiography and those with a history of dyspepsia should have follow-up testing if symptoms recur. Confirmatory testing may also be performed in patients in whom their unknown H pylori status is causing excess worrying or loss of sleep. 1288

5 Previous Diagnosis Made Objectively (ie, Upper Gastrointestinal Tract Series or Endoscopy) Patient With History of Uncomplicated Ulcer Disease Currently Receiving Maintenance Antisecretory Agents Previous Diagnosis Made by Patient History (ie, Clinical Diagnosis ) Patient 50 y or Younger and Without Alarm Symptoms Patient With Dyspepsia Patient Older Than 50 y or With Alarm Symptoms Endoscopy Discontinue Use of Antisecretory Agents for 2 wk, Confirm Results with Nonendoscopic Methods for Active Infection Stop Antisecretory Drug Maintenance Treatment Treat H pylori With d of Clarithromycin and Amoxicillin or Metronidazole Symptoms Recur Consider Other Diagnoses Treat According to Endoscopic Findings (eg, Ulcer, Cancer, GERD, Nonulcer Dyspepsia) Treat H pylori With d of Clarithromycin and Amoxicillin or Metronidazole Resume Maintenance Therapy Assess H pylori Status by UBT or Possibly Stool Antigen Detection Symptoms Recur UBT Resume Maintenance Therapy Treat H pylori With d of Clarithromycin and Amoxicillin or Metronidazole Assess H pylori Status Using UBT or Possibly Stool Antigen Detection Figure 3. Patients with dyspepsia. These patients should be treated according to their age and presenting symptoms. Those older than 50 years and those of any age with alarm symptoms should undergo endoscopy. Patients 50 years or younger and without alarm symptoms should be evaluated for Helicobacter pylori infection using blood antibody testing. Patients who are positive for H pylori should be treated with 10 to 14 days of a twice-daily regimen that includes a proton pump inhibitor (PPI) or ranitidine bismuth citrate (RBC), clarithromycin, and amoxicillin or metronidazole. Items listed with an asterisk and dagger are explained in the legend to Figure 1. GERD indicates gastroesophageal reflux disease. Figure 2. Patients with previous uncomplicated ulcer disease currently receiving maintenance antisecretory agents. Determination of Helicobacter pylori status in these patients should be made using blood antibody testing. Patients who are positive for H pylori should be treated with 10 to 14 days of a twice-daily regimen that includes a proton pump inhibitor (PPI) or ranitidine bismuth citrate (RBC), clarithromycin, and amoxicillin or metronidazole. Patients who are negative for H pylori can stop taking maintenance antisecretory agents provided that a history of uncomplicated peptic ulcer disease was the sole reason for its use. Items listed with an asterisk and dagger are explained in the legend to Figure 1. MANAGEMENT OF PERSISTENT H PYLORI INFECTION AFTER TREATMENT Patients who remain positive for H pylori after completion of an effective anti H pylori regimen should be assessed with regard to treatment compliance. However, many patients may continue to experience symptoms or remain positive for H pylori despite full treatment compliance. 77 ALTERNATIVE REGIMENS IN PATIENTS FAILING INITIAL H PYLORI THERAPY The choice of an alternative regimen should be based on the initial treatment regimen. For example, if triple therapy consisting of a PPI or ranitidine bismuth citrate, clarithromycin, and amoxicillin was used as first-line treatment, the second treatment course should consist of a PPI, metronidazole, bismuth subsalicylate, and tetracycline Alternatively, patients who do not respond to the initial treatment course may be referred to a gastroenterologist for further workup. It is recommended that patients who do not respond to an initial and a secondary course of anti H pylori therapy be referred to a gastroenterologist. These patients often require endoscopy with biopsy and culture for the determination of antibiotic resistance. Further therapy would then be based on the resistance patterns detected. SUMMARY AND RECOMMENDATIONS Helicobacter pylori is a ubiquitous organism that is associated with histological gastritis, peptic ulcer disease, gastric mucosa-associated lymphoid tissue lymphoma, and an increased risk of gastric adenocarcinoma. Studies have documented that cure of the infection is associated with ulcer healing, symptom resolution, and cure of the H pylori related ulcer disease. Cure of H pylori infection reduces the morbidity associated with ulcer disease, conserves health care resources, and frequently eliminates the need for maintenance antisecretory drug therapy. Figures 1, 2, and 3 are proposed to aid physicians in caring for patients with a newly diagnosed ulcer, a previous history of peptic ulcer disease, and dyspepsia, respectively. Patients with confirmed ulcer disease should be evaluated for H pylori infection. Nonendoscopic testing 1289

6 for H pylori infection is also recommended for individuals 50 years and younger with symptoms suggestive of ulcer disease and without alarm symptoms suggestive of malignancy. Other subgroups of individuals might also warrant H pylori evaluation. The method of H pylori detection depends on the patient s clinical presentation. Regardless of how or why they were diagnosed, patients who are positive for H pylori should be offered treatment with an effective anti H pylori regimen. After treatment, patients with documented ulcer disease warrant follow-up evaluation of their posttreatment H pylori status. Accepted for publication September 15, This work was supported by an unrestricted educational grant from TAP Pharmaceuticals Inc, Deerfield, Ill. Corresponding author: Walter L. Peterson, MD, Veterans Affairs Medical Center (111 B-1), 4500 S Lancaster Rd, Dallas, TX REFERENCES 1. Parsonnet J. Helicobacter pylori and gastric cancer. 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