Medical researchers have found the strongest evidence yet that a recently discovered bacterium may be an underlying cause of gastritis and stomach ulcers.
Unknown until 1983 when it was first identified by Australian scientists, the bacterium has been studied intensively by researchers who believe that its discovery could lead to new treatments and perhaps to cures with antibiotics of some cases of gastritis and ulcers.
In the latest study, conducted at the Hospital for Sick Children in Toronto, doctors found the bacterium, known as Campylobacter pylori , present in the stomach linings of seven of 10 children whose gastritis could not be explained in other ways. The organism was absent in eight children whose gastritis had a known cause.
The spiral-shaped bacterium was absent also in all 49 youngsters whose stomach linings showed no signs of the inflammation that is characteristic of gastritis, Dr. Brendan Drumm and his colleagues reported in today's issue of the New England Journal of Medicine.
Gastritis is an inflammation of the lining of the stomach that can progress to become ulcers.
Millions of Americans have gastritis and 10% of the population has peptic and duodenal ulcers. Gastritis commonly is caused by the ingestion of alcohol, aspirin and other drugs, some foods and by certain other intestinal diseases. But, especially in children, a large number of cases cannot be explained in those ways, although the symptoms of nausea, abdominal pain and vomiting are the same, according to the researchers.
Since 1983 a number of other researchers have associated C. pylori with gastritis and the progression to ulcers, but most experts have been unwilling to conclude that the presence of the bacterium in gastritis patients proves that it is the cause of either illness.
While the Canadian doctors admit that their study does not provide the definitive proof, they said that their findings are another step toward that conclusion. This is because none of the previous studies had divided subjects into those with known causes of gastritis and those with an unknown cause and found the bacterium present only in the unknown cause group.
Found 100 Years Ago
Spiral-shaped bacteria resembling C. pylori were first seen in tissue from human stomachs 100 years ago, but researchers then lacked the techniques and instrumentation that made the present study possible.
The discoverers of C. pylori , Drs. Barry J. Marshall and J. Robin Warren of Perth, Australia, speculated that ulcers develop from gastritis because the bacteria-infected cells become more susceptible to stomach acid, which then is able to erode the damaged stomach lining. Others have shown that the bacterium has the ability to penetrate the mucus layer in the stomach and into cells.
But skeptics point out it is possible that the bacterium has entered the cells only because the cells had been previously damaged in some manner. They have suggested that the unknown cause of the previous cell damage may be the real cause of gastritis.