HELICOBACTER PYLORI
Background information
What is H. Pylori?
Helicobacter pylori is a vibro-shaped, flagellate, gram-negative bacterium,
which was first observed in the human stomach around a century ago.(1). Its significance was not understood so it was quickly
forgotten.
Australian scientists, Barry Marshall and Rob Warren, first successfully
cultured Helicobacter pylori in the early 1980s when it was found to be
pathogenic. This discovery has been described as 'the most significant advance
made in gastroduodenal pathology this century'(2).
Who gets infected by Helicobacter and how?
Helicobacter pylori infects most of the world's population. Infection rates
in the populations of under-developed countries seem especially high. In
Britain, prevalence increases with age. In line with the normal population of
industrialised nations, estimates indicate prevalence approaches 50% at age 50
years.(3) Colonisation is most common in childhood,
particularly in association with living conditions where hygiene may be poor.(3) Increased prosperity and a higher standard of living in
the West may account for the relatively low prevalence seen among children and
young people compared to those from under-developed countries where 80% of
young adults may be infected.(2)
Infection is though to be transmitted mainly by the faecal-oral route and to
a lesser degree by the oral-oral route as the bacterium has been found in
saliva and in dental plaque.(2)
How is Helicobacter pylori infection detected?
Currently, in the UK, Helicobacter pylori are commonly diagnosed by serology
(blood tests for antibodies to the bacteria antigens) and by breath-tests to
detect radio-labelled urea. In the latter, the patient swallows a small amount
of radio-labelled urea and breathes into a sealed bag for half an hour.
Detection of ammonia and bicarbonate indicates the presence of H. pylori.
References
1. Krientzw W, Weber Das Auftreten Von
Mageninhalt bei Carcinoma Ventriculi, Deutsche Mediziniche Wochenschrift 1906;
22: 872.
2. Axon ATR, Helicobacter pylori infection, J Antimicrob
Chemother (1993); 32, Suppl A; 61-68.
3. Ormand J et al, Helicobacter pylori: Controversies and an
Approach to Management, Mayo Clin Proc 1990; 65: 414-26.
H Pylori
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