Reports of strong associations in small observational studies without appropriate adjustment for potential confounding factors were not generally confirmed by larger and better- design ed studies .
The available evidence indicates that there is no strong association between H pylori and dyspepsia , but there is insufficient evidence to confirm or refute the existence of a modest association
BACKGROUND Previous studies have yielded conflicting results and substantial uncertainty about any independent association of Helicobacter pylori infection with dyspepsia , and about any benefits of antibiotic treatments for nonulcer or uninvestigated dyspepsia .
OBJECTIVES To perform a systematic review of the literature to determine whether chronic infection with H pylori is relevant to nonulcer or uninvestigated dyspepsia .
Campylobacter pylori in Japan: Bacteriological feature and prevalence in healthy subjects and patients with gastroduodenal disorders
Summary The presence ofCampylobacter pylori was investigated in biopsy specimens obtained during  gastrofiberscopy  from 103 consecutive patients prospect ively . Patients included 25 with gastric ulcer , 4 with duodenal ulcer , 5 with coexisting gastroduodenal ulcer , 31 with gastroduodenal ulcer with gastritis , 27 with gastritis , 3 with gastric polyps and 8 with gastric cancer . Results were compared with 20 healthy control subjects who were endoscopically normal . Two specimens each were taken from 3 sites in the stomach . One part was used for a histological study to examine the presence of the organisms . The other part was cultured using Skirrow ’s agar microaerophilically .  Conventional microflora and C. pylori were examined in gastric contents of some cases . Bacteriological features of isolated strains of C.pylori were identical to the NCTC strain . C.pylori was the most dominant organism in gastric contents at any pH level . Detection rates of C.pylori by bacteriological culture were 96 % in gastric ulcer , 100 % in duodenal ulcer , 80 % in coexisting gastroduodenal ulcer , 84 % in gastroduodenal ulcer with gastritis , 70 % in gastritis , 100 % in gastric polyps and 100 % in gastric cancer , and the percentages recognized by histological studies were 81,100,100 , 84 , 71 , 67 , and 57 % , respectively . The values in healthy controls were 55 % by histological and bacteriological methods ( P<0.001 compared with overall ulcer patients ) . These results supported the close association between C.pylori and gastroduodenal diseases
Reports of strong associations in small observational studies without appropriate adjustment for potential confounding factors were not generally confirmed by larger and better- design ed studies .
The available evidence indicates that there is no strong association between H pylori and dyspepsia , but there is insufficient evidence to confirm or refute the existence of a modest association
BACKGROUND Previous studies have yielded conflicting results and substantial uncertainty about any independent association of Helicobacter pylori infection with dyspepsia , and about any benefits of antibiotic treatments for nonulcer or uninvestigated dyspepsia .
OBJECTIVES To perform a systematic review of the literature to determine whether chronic infection with H pylori is relevant to nonulcer or uninvestigated dyspepsia .