Helicobacter infection: interesting questions.

Helicobacter pylori infection is a common, usually lifelong, infection that is found worldwide.

Where is it prevalent?

What diseases does it cause does it cause? It  causes peptic ulcer disease, non-ulcer dyspepsia, adenocarcinoma of the stomach and gastric mucosa–associated lymphoid tissue lymphoma (MALToma). On the basis of compelling evidence, the World Health Organization (WHO) has classified H. pylori as a group 1 carcinogen leading to gastric adenocarcinoma. In addition to Japan, areas with an increased incidence of gastric carcinoma attributable to this infection include the Middle East, Southeast Asia, the Mediterranean, Eastern Europe, Central America, and South America. Immigrants who grew up in regions of the world with a high incidence of H. pylori infection (e.g., Eastern Europe and East Asia) and who now reside in the United States or Western Europe are also at increased risk for gastric cancer. the prevalence of H pylori in Pakistan is given in an article  Vol 28, No 4 (2012) > Rasheed from the Pakistan Journal of Medical Sciences below.

How can we test for it?

Urea breath test, stool antigen for H pylori (cheaper). Withhold PPI for a week before testing. Serology only works in high prevalence areas (more than 30% prevalence), look for the organism in a gastric biopsy specimens.

When should we test for H pylori?

We should test for H pylori preferably with non-invasive testing, when the patient has a peptic ulcer or symptomatic non-ulcer dyspepsia, gastric carcinoma, gastric MALToma, in a patient on long term aspirin or prolonged NSAId therapy or who has been treated for H pylori in the past and 30 days after presumably successful therapy. Also test in unexplained iron deficiency anemia and thrombocytopenia.

What are the risk factors for acquiring H pylori infection?

The number of infected people has persisted or even increased over the past three decades because of population growth and because of reinfection and recrudescence due to unsuccessful eradication. So consider overcrowding, shared utensils, poor socioeconomic status and exposure to endoscopy.

Conditions outside the gastrointestinal tract have also been associated with H. pylori infection. An observed association with coronary artery disease probably reflects shared risk factors, such as poverty and suboptimal nutrition.

How can we treat it?

Answers to some of these questions are given in these key clinical  taken from the NEJM.

Helicobacter pylori Infection

• Testing for H. pylori is recommended in patients with peptic ulcer disease, gastric cancer, or gastric mucosa–associated lymphoid tissue lymphoma (MALToma). Other recommended indications for testing include dyspepsia, prolonged use of nonsteroidal antiinflammatory drugs or aspirin, unexplained iron-deficiency anemia, and immune thrombocytopenia.
• Testing for H. pylori can be performed directly on biopsy specimens obtained during endoscopy or performed by means of the stool antigen test or urea breath test. Proton-pump inhibitors (PPIs) interfere with the detection of bacteria and must be discontinued before any testing is performed.
• Several regimens are considered to be acceptable for initial treatment. The presence of an allergy to penicillin, previous exposure to macrolides, and high levels of macrolide resistance where the patient lives or has lived (if information is known) are relevant in choosing a regimen.
• After treatment, it is essential to document clearance of the infection, typically by means of a stool antigen test or urea breath test performed 1 month after the completion of antibiotic therapy (again, while the patient is not taking a PPI).
• Should retreatment be indicated, a different regimen that avoids repetitive use of the same antibiotic agents is recommended.

A patient has unexplained iron deficiency anemia. Can it be linked to H pylori infection? Can thrombocytopenia be associated with this organism?

Unexplained iron-deficiency anemia and immune thrombocytopenia have been associated with H. pylori infection; although the pathogenesis is not well understood, reports of successful treatment of H. pylori infection leading to an increased hemoglobin level or higher platelet count suggest causal relationships.

Given above are therapy guidelines being used in USA and elsewhere taken from the March 21, 2019. N Engl J Med 2019; 380:1158-1165.

Hope you find this useful.