December 06, 2001
It was a dramatic and impulsive act by an Australian doctor that took the treatment of stomach ulcers into a new realm. Peta Newbold reports.
In the early '80's it was medical heresy to suggest that a bug could survive in the acid environment of the stomach. So when a Perth pathologist, Dr Robin Warren claimed the unusual bacteria he had spotted had some role in causing stomach inflammation, no one took much notice.
That is until Warren's colleague, trainee gastroenterologist Barry Marshall decided to swallow a solution containing the bug, to prove it caused disease.
The symptoms began about a week later. He suffered vomiting and pain as his stomach became inflamed. It was caused by Helicobacter pylori (H. pylori) and according to Senior lecturer in medical microbiology at the University of New South Wales, Dr Hazel Mitchell, the discovery was of "absolutely unbelievable significance. It completely turned around our understanding of ulcer disease, and gastric cancer.
We used to believe stomach ulcers were caused by too much acid," she said. "When we gave drugs to treat the acid the ulcers would go away. The problem was they would always come back and we didn't know why until we found H. pylori."
What is Helicobacter pylori?
- It is a bacterium or germ that lives in the inner lining of the stomach of most of the world's populations.
- Click here to see a short movie of living Helicobacter pylori movie
- It causes inflammation of the lining of the stomach but most people have no symptoms and it doesn't progress to cause disease. However in the unlucky few it results in duodenal ulcer, gastric ulcer and even gastric cancer.
How common is the infection in Australia?
- About 40 per cent of people over 40 years of age are infected compared with less than 10 per cent of children.
- H. pylori is more common in older people and in those who have migrated from the developing world in people from a poorer background, and in those living in institutions.
How do I get it?
- No-one is really sure but it's likely people become infected by coming into contact with stomach contents of an infected person i.e. vomit, sharing foods or eating utensils.
The diseases caused by H. Pylori
Peptic Ulcers: An ulcer is a break in the lining of the stomach or upper small bowel, (the duodenum). Ulcers occurring in these areas are often known by the generic name, peptic ulcers. Specifically they are:
- 90 per cent are caused by H. pylori where the damage breaks down the resistance to the acid of the lining of the duodenum. This becomes the ulcer, which causes pain in the upper part of the abdomen.
- Small proportions of ulcers cause serious complications such as bleeding or perforation (bursting).
- Found in the main stomach. H. pylori is the cause of about 70 per cent of stomach ulcers.
- The symptoms and complications are the same as for duodenal ulcers.
- Most of the remaining 30 per cent are due to non-steroidal anti-inflammatory drugs (NSAIDs) like aspirin.
Treatment of Peptic Ulcer
Ulcers can be easily cured with drugs that stop acid but there is a very high chance that the ulcer will come back if H. pylori is not eliminated. If H. pylori infection is cured, the risk of the ulcer returning is very low, (unless NSAIDs are taken).
- One of the world's most common cancers - more than a million people die each year.
- H. pylori infection increases the risk of some forms of cancer of the stomach but many more factors also have to be in place.
- We don't clearly understand what causes it but a high salt diet or a low intake of green vegetables appears to be significant in certain populations.
- Stomach cancer is becoming an uncommon cancer in Australia as the number of people infected declines.
- Dyspepsia is used to describe pain, discomfort or other symptoms in the upper abdomen. Most people with dyspepsia do not have an ulcer.
- Some of these people have H. pylori infection but only in a small number does the pain subside when the germ is treated.
Should I be tested for Helicobacter pylori?
- NO if you are healthy because most people infected with H. pylori have no symptoms.
- YES, If there is a history of ulcer disease.
- MAYBE if you have dyspeptic symptoms and you should talk to your doctor.
Testing for H. pylori To analyse a sample of exhaled breath. This is because H. pylori in the stomach is able to convert a naturally occurring substance called urea into the gas carbon dioxide. If specially labelled urea is swallowed, labelled carbon dioxide can be detected.
Can detect current or recent infection but accuracy can vary. They are not useful for checking whether the infection has been successfully treated.
A flexible tube is passed into the stomach, a procedure that is generally safe and painless. This allows small samples to be taken from the lining of the stomach.
Treatment of H. pylori
- Unfortunately there is no ideal treatment and no single drug is effective.
- A number of drug combinations are effective in 80-90 per cent of people.
- The drugs most commonly used include ulcer healing drugs and antibiotics.
- Side effects may include nausea, taste disturbances, diarrhoea, skin rashes and interactions with other medications. It is important to tell your doctor if you have ever had any side effects with antibiotics.
An anti-Helicobacter pylori vaccine
A vaccine that not only prevents infection but also cures it is being developed by an Australian company CSL Ltd, but much of the early was done at the medical microbiology department at the University of New South Wales. Dr Mitchell said, "We were one of the first to demonstrate that a vaccine against this bacterium could be a possibility and if it's successful, it would be enormously significant, saving thousands of lives in many countries, particularly in the developing world."
The University of New South Wales Helicobacter Research Group
Gastroenterological Society of Australia
By Peta Newbold
Reprinted with permission from Editforce