In 1982 two Australians Robin Warren and Barry Marshall presented their findings of a strange bacteria that lives in the human stomach. These bugs became known as Helicobacter pylori and as the cause of the common condition gastritis (inflammation of the stomach).
H. pylori look like little curved rods with a bank of structures called flagella at one end. The flagella beat like arms to propel the bacteria around the stomach. Around 40% of the UK population are infected by the germs and in approximately eight to nine out of ten people who have the condition, it does not cause any symptoms.
Here, London gastroenterologist Dr Aathavan Loganayagam explains how the bacteria is spread, what happens if it’s left unnoticed and whether the condition is curable.
How are the bacteria spread?
Helicobacter pylori normally infect the stomachs of children where, in most cases, they stay forever. In developed countries like the UK, the H. pylori are likely to be spread from mouth to mouth and mother to child. In developing countries, it might also be spread in contaminated water, however, this is not proven.
What happens if H. pylori is untreated?
Most infected people are blissfully unaware of these germs. For around one in five infected people, gastritis can, many years later, lead to one of several diseases including peptic ulcers, which are open sores in the lining of the stomach.
H. pylori infection can also cause two types of cancer. These are the rare MALT lymphoma and a stomach cancer called gastric adenocarcinoma.
Gastric adenocarcinoma is the fifth most common cause of death due to cancer in the world and around7000 new cases are diagnosed in the UK each year.
At least 90% of these cancers are thought to be caused by H. pylori with this disease occurring due to genetic abnormalities that develop in stomach cells as a result of constant and severe gastritis.
How is H. pylori diagnosed?
Patients with ulcers or gastric problems are usually tested with the following three tests:
- Blood test - to look for antibodies
- Stool test - to detect bits of bacteria in the faeces
- Breath test – which detects an enzyme produced by H. pylori in the stomach. This involves drinking a special solution that is broken down by the enzyme, producing a compound that is breathed out and measured.
The infection may be found at the same time as a peptic ulcer or gastroduodenitis with a test called endoscopy. H. pylori can be detected by a number of methods, such as looking at samples under a microscope, using a chemical reaction or growing it in the laboratory.
How is H. pylori treated?
A single antibiotic would be prescribed to treat most bacterial infections but treating an H. pylori infection is far more complex. It commonly involves two or three antibiotics, delivered with a drug called a proton pump inhibitor, which temporarily reduces acid secretion in the stomach.
The development of resistance to antibiotic treatments is becoming a major concern for many disease-causing bacteria and H. pylori are no exception. This means that frontline treatments aren’t always able to immediately eradicate the infection.
Some people who undergo treatment don’t actually clear the infection in the first go although they do normally do so with subsequent alternative drug combinations.
Is H. pylori curable?
Since it was discovered by Marshall and Warren that H. pylori cause gastritis, it means that peptic ulcers can now be cured. In many countries including the UK, these have now become relatively rare conditions. The discovery that stomach cancers are caused by H. pylori has revealed a way of preventing the disease. Nowadays, people diagnosed with H. pylori have the infection treated, which greatly reduces their chance of developing this cancer.
If you are concerned about H. pylori then do not hesitate to have a check-up with Dr Loganayagam.