8 Things About Helicobacter pylori (H. pylori) Infection

Helicobacter pylori cause one of the most common chronic infections in humans, affecting about 31% of Singaporeans. This article will highlight the 8 essentials of this gastrointestinal disease and infection that you should know, and find out why it is important to get it treated!

1. About the organism – Helicobacter pylori (H. pylori)

Helicobacter pylori, or H. pylori in short, is a bacterium that infects the stomach, often during childhood. It produces a substance that enables it to neutralise gastric acid and withstand the harsh acidic environment of the gut. The bacteria can also burrow into the less acidic mucous layer of the stomach, where it attaches to the cells, and evades the body’s immune system.

2. How H. pylori harm the gut

H. pylori can damage stomach tissues and the first part of the small intestine (duodenum).

By neutralising gastric acid, the bacteria weaken the protective lining of the stomach, making stomach cells more susceptible to damage by acid and digestive fluids, which can lead to sores and ulceration. When the bacteria stick to gut cells, it causes the area to become inflamed as well. It can also increase gastric acid production, although the exact mechanism is poorly understood. 

3. Transmission of H. pylori

It is not known exactly how the bacteria infect the body, but it is postulated to be transmitted via saliva, vomit, faeces, or the consumption of contaminated food and water. 

4. Risk factors for H. pylori infection

• Overcrowded living environments 
• Unsanitary food and water supply 
• Living with an infected person 
• Underdeveloped regions

5. Symptoms of H. pylori infection

Most infected individuals are usually asymptomatic. However, should symptoms occur, patients might experience the following: 

• Abdominal pain that may be worse on an empty stomach 
• Bloating
• Frequent burping
• Early satiety
• Lack of appetite
• Nausea or vomiting

Immediate medical attention should be sought if these are observed:

• Severe and/or persistent abdominal pain
• Bloody or dark-coloured stools
• Bloody or dark-coloured vomitus (coffee-ground vomit)
• Swallowing difficulties

If there are any other symptoms that persist or are of concern, a physician should be consulted as soon as possible.

6. Testing for H. pylori infection

Some of the methods used to detect H. pylori include: 

• Carbon-urea breath test (C-UBT): The patient consumes a special substance (e.g., a solution or pill) that contains labelled urea. If H. pylori are present, it can break down the urea, and the products can be measured from a person’s breath.
• Stool test:
  • Stool antigen test: Looks for foreign proteins (antigens) associated with the bacteria in stool samples.
  • Stool culture test: Looks for the bacteria within the stool sample.

Preferred for children who may not be able to cooperate for C-UBT:

• Serological assays: Check blood for antibodies against H. pylori. But test is unable to distinguish between current and previous infection.
• Gastroscopy: Scope test that looks at the tissue of the oesophagus, stomach, and duodenum. Samples may be taken during the procedure for analysis through:
• Rapid urease testing 
• Histological examination
• Bacterial culture and antibiotic susceptibility testing 

Use of antibiotics/bismuth and proton pump inhibitors (PPI) within 4 weeks and 2 weeks respectively can decrease the sensitivity of CUB-T, stool test, and endoscopy. Therefore, it is recommended for patients to discontinue PPI 2 weeks before taking the tests for diagnosis, and at least 4 weeks after completing their H. pylori antibiotic/bismuth treatment regime.

Apart from testing for the presence of H. pylori infection, confirming the elimination of the bacteria after completion of therapy should also be performed for all patients. This can be done using all the tests mentioned above, except for serological assays. 

7. Treatment for H. pylori infection

All patients established to have the infection should receive treatment which typically includes: 

• A potent acid suppressor, PPI: Protects the stomach and makes bacteria more vulnerable to antibiotics
• The use of at least 2 antibiotics in combination: Prevent antibiotic resistance

The ideal duration of treatment is 14 days, although shorter periods of 7 and 10 days may also be prescribed at the physician’s clinical discretion. Patients should be advised to comply strictly with their treatment regimen, as a compliance rate of less than 80% is associated with lower treatment efficacy and treatment failure. Unsuccessful initial therapy could also result in recurrence of the condition and promote bacterial antibiotic resistance.

8. Complications of H. pylori infection

There are several complications linked to the infection. 

• Chronic dyspepsia
• Gastritis: Bacteria can irritate the stomach, resulting in inflammation. 
• Peptic ulcer disease (PUD): As the bacteria harm the protective lining of the gut and small intestine, it can lead to the development of ulcers. H. pylori is known to be a major risk factor for PUD.  
• Gastric malignancies: H. pylori is a major risk factor for certain types of stomach cancer. Prolonged inflammation causes abnormal changes in the stomach lining, predisposing the cells to become cancerous.  

It is therefore important for patients to adhere to their treatment plan strictly for successful eradication of the Helicobacter pylori infection, and preventing complications from arising.