Helicobacter Pylori

What is Helicobacter Pylori?

Helicobacter pylori, often referred to as H. pylori, is a type of bacteria that lives in the digestive tract. It is spiral-shaped and can survive in the stomach's harsh acidic environment. Once inside the body, it can multiply and damage the stomach's protective lining and the upper part of the small intestine (duodenum).  It was discovered by two Australians, Barry Marshall (a gastroenterologist) and Robin Warren (a pathologist), for which they won the Nobel Prize. 


This bacterium is incredibly common—about 30-40%  of the world’s population has it, although many people never experience symptoms. However, in some individuals, H. pylori can cause inflammation, ulcers (sores in the stomach or intestine), and in more serious cases, increase the risk of developing stomach cancer.

Impact of Helicobacter Pylori on Anatomy and Health

When H. pylori infects the stomach, it starts by damaging the mucosal lining, which normally protects the stomach from its own acid. As this lining becomes inflamed or thinned, acid can irritate and damage the tissue underneath. This process may lead to several gastrointestinal problems:

  • Gastritis: Inflammation of the stomach lining, which may cause pain or discomfort.
  • Peptic Ulcers: Open sores in the lining of the stomach or duodenum.
  • Stomach (Gastric) Cancer: Long-term infection may increase the risk of developing certain types of stomach cancer.
  • MALT Lymphoma: A rare type of stomach cancer associated with chronic H. pylori infection.


Beyond the stomach, H. pylori can influence your overall health. Some studies suggest a link between this infection and conditions such as iron deficiency anaemia or vitamin B12 deficiency, due to impaired absorption caused by stomach inflammation.


Risk Factors for Helicobacter Pylori

Anyone can become infected with H. pylori, but certain groups are more likely to carry or develop problems from the infection. Risk factors include:

  • Age: Infections often begin in childhood.
  • Living Conditions: People living in overcrowded homes or areas with poor sanitation are at higher risk.
  • Geographic Region: It is more common in developing countries.
  • Household Exposure: Close contact with an infected family member can increase the chance of transmission.
  • Low Socioeconomic Status: Limited access to clean water and good hygiene increases risk.
  • Weakened Immune System: Individuals with compromised immune systems may be more vulnerable to developing symptoms.


Causes of Helicobacter Pylori Infection

The main cause of H. pylori infection is direct person-to-person transmission. The bacteria spread in the following ways:

  • Oral-to-Oral Contact: Such as through kissing or sharing utensils.
  • Fecal-Oral Route: From contaminated food, water, or poor hygiene practices, especially after using the bathroom and not washing hands properly.
  • Contaminated Surfaces: H. pylori can survive briefly on surfaces and be transmitted through contact.


Once in the body, the bacteria burrow into the stomach lining and produce enzymes that weaken the stomach's protective mucus, allowing acid and bacteria to irritate the lining.


Symptoms of Helicobacter Pylori Infection

Many people infected with H. pylori do not exhibit symptoms. When symptoms do appear, they are often related to the stomach and digestive system. These may include:

  • Burning or aching pain in the abdomen
  • Bloating and feeling full quickly when eating
  • Nausea and vomiting
  • Loss of appetite
  • Unintentional weight loss
  • Frequent burping or gas
  • Dark or bloody stools (a possible sign of bleeding ulcers)


Symptoms can vary in severity. Sometimes, the infection may be silent for years before causing noticeable problems. The symptoms may become more severe and persistent if ulcers or serious complications develop.


Prevention of Helicobacter Pylori Infection

There is no vaccine for H. pylori, but good hygiene and food safety practices can help reduce the risk of infection. The following preventive measures are recommended:

  • Practice Good Hand Hygiene: Always wash your hands thoroughly with soap and water after using the toilet and before preparing or eating food.
  • Drink Safe Water: Avoid drinking untreated or contaminated water, especially when travelling in countries where sanitation is poor.
  • Eat Food That is Properly Prepared: Avoid raw or undercooked foods from questionable sources.
  • Don’t Share Eating Utensils or Toothbrushes: Reduce the potential for oral transmission by not sharing personal hygiene items.


Stages of Helicobacter Pylori Infection

H. pylori infection progresses through several stages if left untreated. Not everyone will go through all stages, and progression can vary widely depending on the person’s immune system, bacterial strain, and other environmental factors.

  • Initial Colonisation: After entering the body, usually during childhood, the bacteria settle in the stomach lining. Most people do not notice any symptoms at this stage.
  • Chronic Gastritis: Over time, the bacteria cause stomach lining inflammation. This stage can remain silent for years or cause mild discomfort, bloating, or indigestion.
  • Peptic Ulcer Development: Continued inflammation and damage may lead to sores (ulcers) in the stomach or duodenum. This stage is usually when people seek medical help due to pain or digestive symptoms.
  • Atrophic Gastritis and Intestinal Metaplasia: In long-standing cases, the stomach lining becomes thin and loses its normal structure. The cells may begin to change (metaplasia), increasing the risk of stomach cancer.
  • Gastric Cancer or Lymphoma (in rare cases): A small percentage of people, especially those infected with more aggressive strains, may eventually develop gastric adenocarcinoma (stomach cancer) or MALT lymphoma (a cancer of immune cells in the stomach lining).

Diagnosis of Helicobacter Pylori

Several reliable methods are available to detect H. pylori. The choice of test may depend on symptoms, age, medical history, and whether the patient is taking acid-reducing medication or antibiotics.

  • Urea Breath Test: This is one of the most accurate and non-invasive tests. The patient swallows a special urea capsule. If H. pylori is present, the bacteria break it down, releasing carbon dioxide, which is detected in the breath.
  • Stool Antigen Test: A sample of stool is tested for proteins (antigens) from H. pylori. This is simple and useful for diagnosis and checking if treatment has worked.
  • Blood Test (Serology): Measures antibodies to H. pylori in the blood. It can confirm past exposure but is less useful for determining whether an active infection is present.
  • Endoscopy with Biopsy: Used if ulcers, bleeding, or cancer are suspected. A camera is passed into the stomach, and small tissue samples are taken for testing. This can also detect the severity of any inflammation or ulceration.


Patients should stop taking proton pump inhibitors (e.g., omeprazole) and antibiotics at least 2 weeks before testing, as these can affect the accuracy of certain tests.


Treatment of Helicobacter Pylori Infection

Treatment for H. pylori usually involves a combination of medications taken for 1–2 weeks. The goal is to fully eliminate the bacteria and allow the stomach lining to heal.

  • Antibiotics: Two or more antibiotics are used together to kill the bacteria. Common choices include clarithromycin, amoxicillin, and metronidazole.
  • Proton Pump Inhibitors (PPIs): Medications such as omeprazole or esomeprazole reduce stomach acid, making it easier for antibiotics to work and helping the stomach lining to heal.
  • Bismuth Compounds (optional): Sometimes a bismuth-based medication is added (e.g., in quadruple therapy) to further weaken the bacteria and protect the stomach lining.


This treatment is referred to as:

  • Triple Therapy: PPI + two antibiotics
  • Quadruple Therapy: PPI + two antibiotics + bismuth


It is important to:

  • Complete the full course of treatment even if symptoms improve early
  • Avoid alcohol during treatment
  • Tell your doctor if side effects occur (nausea, diarrhoea, bad taste)


A follow-up test (usually a breath or stool test) is done 4–6 weeks after treatment to ensure the infection has cleared.


What if Helicobacter Pylori Infection is Untreated?

Leaving H. pylori infection untreated can lead to several complications, some of which can be serious or even life-threatening over time:

  • Chronic Gastritis: Ongoing inflammation may lead to long-term digestive discomfort and damage to the stomach lining.
  • Peptic Ulcers: Persistent irritation from H. pylori and stomach acid can create open sores, leading to pain, nausea, and risk of bleeding.
  • Stomach Bleeding: If ulcers erode into a blood vessel, it can lead to vomiting blood or passing black, tarry stools. This is a medical emergency.
  • Perforation:
    In rare cases, ulcers can create a hole in the stomach or intestinal wall, causing severe pain and requiring emergency surgery.
  • Gastric Cancer:
    Long-term infection, especially with high-risk strains like CagA-positive, increases the risk of stomach cancer. This process takes years, but it is a serious concern.
  • MALT Lymphoma:
    A rare form of stomach cancer arising from immune cells. Often, treating the H. pylori infection alone can cure early-stage MALT lymphoma.


Because these complications can develop silently over time, even people without obvious symptoms may benefit from testing and treatment, especially if they have a family history of ulcers or gastric cancer, or live in high-risk areas.