Helicobacter pylori infection

Disease Description (Causes and Symptoms)

• Cause: A spiral-shaped bacterium called Helicobacter pylori settles between the gastric mucosa and mucus layer, causing chronic inflammation. Transmission is known to be possible through person-to-person contact (oral-oral, fecal-oral), contaminated water and food, and medical instruments.
• Pathophysiology: H. pylori invades the mucus layer, causing persistent inflammation in the gastric mucosa, and increases the risk of gastric ulcers and gastric cancer through atrophic changes and intestinal metaplasia. Bacterial and host genetic factors, as well as environmental factors (gastric acid, smoking, etc.), affect the disease phenotype.
• Main symptoms: Often asymptomatic. When symptoms occur, they may include dyspepsia, upper abdominal pain, nausea and vomiting, epigastric pain, and symptoms of gastritis, gastric ulcers, or duodenal ulcers. Complications may include gastric bleeding, perforation, gastric cancer, and lymphoma around the stomach (MALT lymphoma).
• Diagnostic tests: Urea breath test (UBT), stool antigen test, serum antibody test (limited ability to distinguish past infection), and biopsy during upper endoscopy (rapid urease test, culture, histopathology), among others. To confirm eradication after treatment, a UBT or stool antigen test is recommended, performed at least 4 weeks after completion of treatment.

Treatment Methods

• Treatment indications (general recommendations): Eradication therapy is recommended for gastric ulcers; duodenal ulcers accompanied by complications; patients treated for early gastric cancer; MALT lymphoma around the stomach; first-degree relatives of patients with gastric cancer; unexplained iron-deficiency anemia; and chronic idiopathic thrombocytopenia (in some cases). Not all infected people necessarily require treatment.
• Standard drug therapy:
  • First-line treatment (general option): A 14-day combination therapy using a PPI (or P-CAB) + amoxicillin + clarithromycin or metronidazole (may vary depending on local antibiotic resistance rates).
  • In cases of resistance or first-line treatment failure: Bismuth-containing quadruple therapy (bismuth + tetracycline + metronidazole + PPI) or tailored therapy based on the resistance pattern is recommended.
  • Recently, because clarithromycin resistance has increased, selecting a 14-day treatment and considering resistance according to local guidelines has become important.
• Confirmation testing after treatment: Confirm eradication with a UBT or stool antigen test at least 4 weeks after completion of treatment (and it is recommended to stop PPIs for at least 2 weeks before testing).
• Lifestyle management and precautions:
  • Because medication adherence has a major impact on treatment success, the prescribed duration and administration instructions must be followed.
  • It is necessary to check for antibiotic side effects (vomiting, diarrhea, gastrointestinal discomfort, etc.) and drug interactions (e.g., warfarin and some antidepressants).
  • Smoking can increase the risk of eradication failure and gastric cancer, so smoking cessation is recommended.
  • Poorly hygienic eating habits and sharing utensils may increase the risk of transmission, so maintain personal hygiene.

Checklist Before an Outpatient Visit (Items to Prepare and Sample Questions)

• Items to prepare:
  • A list of all medications and supplements currently being taken (including antibiotics and PPIs taken previously)
  • Results of previous upper endoscopy, UBT, stool antigen, and blood tests (if available)
  • A record of when symptoms began and their pattern, aggravating and relieving factors, and bleeding symptoms (black stools, vomiting blood)
  • Family history (especially gastric and other gastrointestinal cancers)
• Items that are useful to confirm in advance during the outpatient visit:
  • Recent experience using antibiotics or macrolides (such as clarithromycin)
  • Whether you are pregnant or breastfeeding
  • Whether you are taking anticoagulants or cardiovascular medications
• Sample questions (to prepare for questions you may receive from the medical staff):
  • When did your symptoms begin recently? How are your symptoms related to eating?
  • Have you ever been diagnosed with peptic ulcer disease or had findings from an upper endoscopy?

Sample General Questions to Ask the Doctor

• "What are the expected side effects of this medication (eradication therapy), and what should I do if the side effects are severe?"
• "If Helicobacter pylori is completely eradicated with treatment, how much does the risk of gastric cancer decrease?"
• "When and with which test should I undergo confirmation testing after treatment?"

Sample Disease-Specific Questions

• "There is a patient with gastric cancer in my family. If I am confirmed to have Helicobacter pylori infection, do I have to receive eradication therapy unconditionally?"
• "My test was positive after first-line treatment. What are the next treatment options (such as bismuth quadruple therapy), and what is the expected success rate?"

Additional guidance: The specific drugs and duration of eradication therapy vary depending on local antibiotic resistance rates, the patient's drug allergies, and medications they are already taking. Please consult your attending physician to determine the schedule for testing before and after treatment and drug interactions.