Background: The aim of this study was to determine whether the amount of He
licobacter pylori and the extent of gastric metaplasia in the duodenal muco
sa Flay critical roles in the pathogenesis of duodenal ulcer.
Methods: Duodenal and gastric biopsy specimens were obtained from H. pylori
-positive patients with duodenal ulcer, gastric ulcer or chronic gastritis.
The extent of gastric metaplasia was evaluated histologically and endoscop
ically using the methylene blue test. In this study, we performed competiti
ve polymerase chain reaction? a highly sensitive and quantitative method fo
r determining the amount of H. pylori gastric and duodenal mucosa. The prev
alence and extent of gastric metaplasia and the amount of H, pylori in the
duodenal bulb in the three patient groups were compared. The correlation be
tween the amount of H. pylori in the duodenum and gastric antrum and extent
of gastric metaplasia were also determined.
Results: The prevalence and extent of gastric metaplasia and the amount of
H. pylori in the duodenal bulb in patients with duodenal ulcer were much hi
gher than in patients with gastric ulcer or chronic, gastritis. a positive
correlation was found between the amount of H. pylori in the duodenum and t
he extent of gastric bulb and that in the antrum.
Conclusions: The findings of this study indicate that H. pylori colonizatio
n in the: duodenal bulb may play a critically important rule in the pathoge
nesis of duodenal ulcer and that the amount of H. pylori in the duodenal bu
lb may be related to the amount of H. pylori in the gastric antrum and the
extent of gastric metaplasia in the duodenal bulb.