What is Helicobacter pylori infection and whom does it affect?
Helicobacter pylori (commonly just called H. pylori) is a bacterium (germ). It can infect the lining of the stomach and duodenum. It is one of the most common infections in the UK although it is getting less common as time goes by. More than a quarter of people in the UK become infected with H. pylori at some stage in their life. Once you are infected, unless treated, the infection usually stays for the rest of your life.
What problems does Helicobacter pylori cause?
Commonly there are no problems
Most people who are infected with H. pylori have no symptoms or problems caused by the infection. These people do not know that they are infected. A number of H. pylori bacteria may just live harmlessly in the lining of the stomach and duodenum.
Stomach and duodenal ulcers
H. pylori is the most common cause of duodenal and stomach ulcers. About 3 in 20 people who are infected with H. pylori develop an ulcer. An ulcer is where the lining of the stomach or duodenum is damaged by the acid which is made in the stomach, and the underlying tissue is exposed. If you could see inside your gut, an ulcer looks like a small, red crater on the lining of the stomach or duodenum.
The exact way H. pylori causes ulcers in some infected people is not totally clear. Your stomach normally produces acid to help with the digestion of food and to kill bacteria. This acid is corrosive. So, some cells on the inside lining of the stomach and duodenum produce a natural mucus barrier which protects the lining of the stomach and duodenum from the acid. There is normally a balance between the amount of acid that you make and the mucus defence barrier. An ulcer may develop if there is an alteration in this balance allowing the acid to damage the lining of the stomach or duodenum. In some people H. pylori causes inflammation in the lining of the stomach or duodenum. This causes the mucus defence barrier to be disrupted in some way (and in some cases the amount of acid to be increased) which seems to allow the acid to cause inflammation and ulcers.
This is a condition where you have recurrent bouts of indigestion (dyspepsia) which are not caused by an ulcer or inflammation. It is sometimes called functional dyspepsia. H. pylori is sometimes found in people with non-ulcer dyspepsia. Getting rid of H. pylori cures some cases, but makes no difference in most cases. The cause of most cases of non-ulcer dyspepsia is not known.
The risk of developing stomach cancer is thought to be increased with long-term infection with H. pylori. However, it has to be stressed that more than a quarter of people in the UK become infected with this bacterium, and the vast majority do not get stomach cancer. The increased risk is small. Your risk may be greater if you have H. pylori in addition to having a first-degree relative (mother, father, brother, sister or child) who has been diagnosed with stomach cancer.
Gastric mucosa-associated lymphoid tissue lymphoma - a MALToma
This is a rare and unusual type of stomach cancer. Infection with H. pylori is thought play a role in this condition developing.
How is Helicobacter pylori diagnosed?
Various tests can detect H. pylori:
- A breath test can confirm that you have a current H. pylori infection. A sample of your breath is analysed after you take a special drink. Note: prior to this test you should not have taken any antibiotics for at least four weeks. Also, you should not have taken a proton pump inhibitor (PPI) or H2-receptor antagonist medicine for at least two weeks. (These are acid-suppressing medicines.) Also, you should not eat anything for six hours before the test. The reason for these rules is because they can affect the test result.
- An alternative test is the stool antigen test. In this test you give a pea-sized sample of your faeces (stools) which is tested for H. pylori. Note: prior to this test you should not have taken any antibiotics for at least four weeks. Also, you should not have taken a PPI or H2-receptor antagonist acid-suppressing medicine for at least two weeks.
- A blood test can detect antibodies to H. pylori. This is sometimes used to confirm that you are, or have been, infected with H. pylori. However, it can take up to a year for this test to become negative once the infection has cleared. So, it is no use to confirm whether treatment has cleared the infection (if this needs to be known). If needed, the breath test or stool antigen test is usually used to check if an infection has cleared following treatment.
- Sometimes a biopsy (small sample) of the lining of the stomach is taken if you have a gastroscopy (endoscopy). The sample can be tested for H. pylori.
How is Helicobacter pylori cleared from the stomach and duodenum?
H. pylori is killed by certain antibiotics. However, a combination of medicines is needed to get rid of it completely. You need to take two antibiotics at the same time. In addition, you need to take a medicine to reduce the acid in the stomach. This allows the antibiotics to work well in the stomach. You need to take this combination therapy for a week. It is important to take all the medication exactly as directed, and to take the full course.
Combination therapy clears H. pylori in up to 9 in 10 cases if it is taken correctly for the full course. If you do not take the full course then the chance of clearing the infection is reduced. A second course of combination therapy, using different antibiotics, will usually work if the first course does not clear the infection.
Combination therapy is sometimes called triple therapy as it involves three medicines - two antibiotics and an acid-suppressing medicine.
Who should be tested for Helicobacter pylori, and treated if it is found?
If you have recurring dyspepsia (recurring indigestion symptoms)
If you have recurring dyspepsia, it is common practice to test for H. pylori before doing any other tests. If H. pylori is found, then combination treatment is often given. The exact diagnosis may not be known. For example, it might not be clear if the dyspepsia is caused by a duodenal or stomach ulcer, or non-ulcer dyspepsia. These can only be confirmed by having a look down into the gut with a test called gastroscopy (endoscopy). However, if symptoms go after treatment for H. pylori, then that is the end of the matter. You do not need further tests such as gastroscopy. You will not know exactly what caused the symptoms, but it does not matter: if the symptoms have gone, whatever was causing them will have gone!
Other reasons for testing
If you are in one of the following groups, you may be offered a test for H. pylori and offered treatment with combination therapy if it is found. If you:
- Have a duodenal or stomach ulcer. Combination therapy will usually cure the ulcer.
- Have non-ulcer dyspepsia. Combination therapy may work and clear symptoms, but it does not in most cases.
- Have a first-degree relative (mother, father, brother, sister or child) who has been diagnosed with stomach cancer. Treatment is advised even if you do not have any symptoms. The aim is to reduce your future risk of stomach cancer.
- Are taking, or are about to take, long-term anti-inflammatory medication such as ibuprofen, diclofenac, aspirin, etc. The combination of these medicines and H. pylori increases the risk of developing a stomach ulcer.
- Have a MALToma.
- Have atrophic gastritis (inflammation of the stomach lining).
- Have had an operation to remove a stomach cancer.
- Have unexplained iron-deficiency anaemia.
- Have a condition called chronic idiopathic thrombocytopenic purpura. This is an uncommon blood condition where the number of platelets in the blood becomes very low. Some research suggests a possible connection between H. pylori infection and this condition.
After combination therapy, a test may be advised to check that H. pylori has gone (has been eradicated). This test will usually be a breath test or a stool antigen test (described earlier). If a test is done, it needs to be done at least four weeks after the course of combination therapy has finished. In most cases, the test is negative, meaning that the infection has gone. If it has not gone, then a repeat course of combination therapy with a different set of antibiotics may be advised.
Some doctors say that for certain situations, this confirmation of eradication test is not necessary if symptoms have gone. For example, after using combination therapy to treat a duodenal ulcer. In this situation, the fact that symptoms have gone usually indicates that the ulcer and the cause (H. pylori) have gone. But, some doctors say it is needed to play safe. However, for some conditions such as a stomach ulcer, a confirmation of eradication test is usually always advised. Your own doctor will advise if you should have this test following treatment.
Are there any side-effects of combination therapy?
Up to 3 in 10 people develop some side-effects when they take combination therapy. These include: indigestion, feeling sick, diarrhoea, and headaches. However, it is worth persevering for the full course if side-effects are not too bad. A switch to a different set of medicines may be advised if the first combination does not clear the H. pylori, or if it caused bad side-effects and you had to stop taking it.
Further reading & references
- Dyspepsia: Managing dyspepsia in adults in primary care, NICE Clinical Guideline (2004)
- Management of Infection - Guidance for Primary Care, Health Protection Agency (various dates)
- Helicobacter pylori guidelines (various), Health Protection Agency (2008)
- Dyspepsia - proven peptic ulcer, Prodigy (June 2008)
- Malfertheiner P, Megraud F, O'Morain C, et al; Malfertheiner P, Megraud F, O'Morain C, et al; Current concepts in the management of Helicobacter pylori infection: the Maastricht III Consensus Report. Gut. 2007 Jun;56(6):772-81. Epub 2006 Dec 14.
- Shah R; Dyspepsia and Helicobacter pylori. BMJ. 2007 Jan 6;334(7583):41-3.
|Original Author: Dr Tim Kenny||Current Version: Dr Laurence Knott||Peer Reviewer: Dr Tim Kenny|
|Last Checked: 15/12/2011||Document ID: 4266 Version: 40||© EMIS|
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