Helicobacter Pylori Infection
A common stomach bacterium linked to ulcers and gastritis
Quick Facts
- Type: Bacterial infection of the stomach
- Spread: Contaminated food, water, and close contact
- Can cause: Gastritis and peptic ulcers
- Treatment: Combination of antibiotics and acid reducer
Overview
Helicobacter pylori (H. pylori) is a spiral-shaped bacterium that lives in the lining of the stomach. It is one of the most common chronic bacterial infections worldwide and is often acquired in childhood. Many people carry it for life without ever knowing, because it frequently causes no symptoms.
In others, H. pylori weakens the protective mucous layer of the stomach and triggers inflammation, leading to gastritis and peptic ulcers. Over many years, long-standing infection also raises the risk of certain stomach cancers. The good news is that the infection can be detected with simple tests and cured with a course of medication.
Symptoms
Most people with H. pylori have no symptoms. When the infection causes inflammation or ulcers, symptoms may include:
- A dull or burning pain in the upper abdomen, often worse when the stomach is empty
- Bloating, belching, or a feeling of fullness
- Nausea
- Loss of appetite or unintended weight loss
- Frequent indigestion
Warning signs of a complication include vomiting blood or material like coffee grounds, black or tarry stools, and sudden severe abdominal pain. These suggest a bleeding or perforated ulcer and require emergency care.
Causes
H. pylori infection is caused by the bacterium itself, which spreads from person to person and through contaminated food and water.
- Person-to-person spread: Through saliva, vomit, or stool, often within families and households.
- Contaminated food and water: More common where sanitation is limited.
- Childhood acquisition: Most infections are picked up in early life and persist if untreated.
Once in the stomach, the bacterium is able to survive the acidic environment and burrow into the protective mucous layer, where it causes ongoing inflammation.
Risk Factors
- Living in crowded conditions
- Lack of a reliable supply of clean water
- Living in or coming from areas where the infection is common
- Living with someone who has H. pylori
- Acquisition in childhood, which accounts for most infections
Diagnosis
Several reliable tests can detect active H. pylori infection.
- Urea breath test: A breath sample taken after drinking a special solution; a leading non-invasive test.
- Stool antigen test: Detects bacterial proteins in the stool.
- Blood test: Detects antibodies but cannot always tell current from past infection, so it is used less often.
- Endoscopy with biopsy: A camera passed into the stomach to take samples, used when ulcers or other problems need direct examination.
Some medications, including acid reducers and recent antibiotics, can affect test accuracy, so timing is considered when testing.
Treatment
Treatment aims to clear the bacterium and heal any damage it has caused. It typically combines several medicines for one to two weeks.
- Antibiotics: Usually two antibiotics together to overcome resistance and clear the infection.
- Acid-reducing medication: A proton pump inhibitor (PPI) to lower stomach acid and help the lining heal and the antibiotics work.
- Bismuth-containing regimens: Sometimes added to improve cure rates.
It is important to take the full course exactly as prescribed, even if symptoms improve. A follow-up breath or stool test is often done several weeks after treatment to confirm the infection is gone. If it persists, a different combination of antibiotics may be needed.
Prevention
- Wash hands thoroughly with soap and water, especially after using the toilet and before eating
- Drink clean, safe water and eat properly prepared food
- Avoid sharing utensils and drinks when possible
- Complete the full course of treatment if you are diagnosed, to prevent reinfecting yourself or others
- Get tested if you have ulcers or a strong family history of stomach cancer
When to See a Doctor
See a clinician for persistent upper abdominal pain, frequent indigestion, or symptoms suggesting an ulcer, particularly if you take anti-inflammatory painkillers. Testing for H. pylori is often recommended. Seek emergency care for:
- Vomiting blood or material that looks like coffee grounds
- Black, tarry, or bloody stools
- Sudden, severe abdominal pain
- Feeling faint or dizzy, which can signal internal bleeding
Frequently Asked Questions
How do you get H. pylori?
H. pylori spreads from person to person through saliva, vomit, or stool, and through contaminated food and water. Most people acquire it in childhood, often within the household, and may carry it for years without symptoms.
Does H. pylori always cause symptoms?
No. Many people with H. pylori never develop symptoms. The infection becomes a problem when it causes gastritis or ulcers, leading to upper abdominal pain, bloating, nausea, or indigestion. Long-standing infection also raises stomach cancer risk over time.
How is H. pylori treated?
Treatment usually combines two antibiotics with an acid-reducing medicine for one to two weeks, sometimes with bismuth. It is important to finish the entire course, and a follow-up test is often done weeks later to confirm the bacterium is gone.
Can H. pylori come back after treatment?
Reinfection is uncommon in areas with good sanitation but can happen. If a follow-up test shows the infection persists, it usually means the first treatment did not fully clear it, and a different antibiotic combination is then used.
Is H. pylori linked to stomach cancer?
Long-term H. pylori infection is a known risk factor for certain stomach cancers because of the chronic inflammation it causes. Most infected people do not develop cancer, but treating the infection, especially in those at higher risk, can lower that risk.
References
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Helicobacter pylori (H. pylori) and Peptic Ulcers.
- Mayo Clinic. Helicobacter pylori (H. pylori) infection.
- Centers for Disease Control and Prevention (CDC). Helicobacter pylori.
- MedlinePlus, U.S. National Library of Medicine. Helicobacter pylori infections.