H. PYLORI FACT SHEET

What is H. Pylori?
Helicobacter pylori (H. pylori) is a spiral shaped bacterium that is found in the gastric mucus layer or adherent to the epithelial lining of the stomach. H. pylori causes more than 90% of duodenal ulcers and more than 80% of gastric ulcers. Before 1982, when this bacterium was discovered, spicy food, acid, stress, and lifestyle were considered the major causes of ulcers. The majority of patients were given long-term maintenance doses of acid-reducing medications, such as H2 blockers, without a chance for permanent cure. Since we now know that most ulcers are caused by H. pylori, appropriate antibiotic regimens can successfully eradicate the infection in most patients, with complete resolution of mucosal inflammation and a minimal chance for recurrence of ulcers. How common is H. pylori infection?
Approximately two-thirds of the world's population is infected with H. pylori. In the United States, H. pylori is more prevalent among older adults, African Americans, Hispanics, and lower socioeconomic groups.
What illnesses does H. pylori cause?
Most persons who are infected with H. pylori never suffer any symptoms related to the infection; however, H. pylori causes chronic active, chronic persistent, and atrophic gastritis in adults and children. Infection with H. pylori also causes duodenal and gastric ulcers. Infected persons have a 2- to 6-fold increased risk of developing gastric cancer and mucosal-associated-lymphoid-type (MALT) lymphoma compared with their uninfected counterparts. The role of H. pylori in non-ulcer dyspepsia remains unclear.
What are the symptoms of ulcers?
Approximately 25 million Americans suffer from peptic ulcer disease. Each year there are 500,000 to 850,000 new cases of peptic ulcer disease and more than one million ulcer-related hospitalizations. The most common ulcer symptom is gnawing or burning pain in the epigastrium. This pain typically occurs when the stomach is empty, between meals and in the early morning hours, but can also occur at other times. It may last from minutes to hours and may be relieved by eating or by taking antacids. Less common ulcer symptoms include nausea, vomiting, and loss of appetite. Bleeding can also occur; prolonged bleeding may cause anemia leading to weakness and fatigue. If bleeding is heavy, hematemesis, hematochezia, or melena may occur.
Who should be tested and treated for H. pylori ?
Persons with active gastric or duodenal ulcers or documented history of ulcers should be tested for H. pylori, and if found to be infected, they should be treated. To date, there has been no conclusive evidence that treatment of H. pylori infection in patients with non-ulcer dyspepsia is warranted. Testing for and treatment of H. pylori infection are recommended following resection of early gastric cancer and for low-grade gastric MALT lymphoma. Retesting after treatment may be prudent for those with bleeding or otherwise complicated peptic ulcer disease. Treatment recommendations for children have not been formalized. Pediatric patients who require extensive diagnostic work-up for abdominal symptoms should be evaluated by a specialist.
How is H. pylori infection diagnosed?
Several methods may be used to diagnose H. pylori infection. Serological tests that measure specific H. pylori IgG antibodies can determine if a person has been infected. The sensitivity and specificity of these assays range from 80% to 95% depending upon the assay used. Another diagnostic method is the breath test. In this test, the patient is given either ¹³C or ^{1 4}C-labeled urea to drink. H. pylori metabolizes the urea rapidly, and the labeled carbon is absorbed. This labeled carbon can then be measured as CO₂ in the patients expired breath to determine whether H. pylori is present. Upper esophagogastroduodenal endoscopy is considered the reference method of diagnosis. During endoscopy, biopsy specimens of the stomach and duodenum are obtained and the diagnosis of H. pylori can be made by several methods:

• The biopsy urease test is a colorimetric test based on the ability of H. pylori to produce urease; it provides rapid testing at the time of biopsy.

• Histologic identification of organisms is considered the gold standard of diagnostic tests.

• Culture of biopsy specimens for H. pylori requires an experienced laboratory and is necessary when antimicrobial susceptibility testing is desired.

Eradication rates range from 70% to 90% depending on the regimen used. Currently, five H. pylori treatment regimens are approved by the Food and Drug Administration (FDA) (Table 1); however, several other combinations have been used successfully. Antibiotic resistance and patient noncompliance are the two major reasons for treatment failure.