Long-term sequelae of Helicobacter pylori gastritis

Use of serum-specific immunoglobulins A and G for detection of Helicobacter pylori infection in patients with chronic gastritis by immunoblot analysis

Multiple invasive and noninvasive tests for detecting Helicobacter pylori infection are available. The current "gold standard" for the diagnosis of H. pylori infection requires histology and the rapid urease test. Our aim was to test the performance of immunoglobulin A (IgA) and IgG immunoblot assays in comparison with that of the gold standard tests for the diagnosis of H. pylori infection. Ninety patients who underwent gastroscopy were analyzed in a prospective study. Fifty-nine of them were defined to be H. pylori positive by the gold standard tests. The IgA and IgG immunoblot assays correctly identified H. pylori infection in 17 and 58 of these patients, respectively, indicating that determination of IgA antibodies seems to be of low diagnostic value for H. pylori infection. In contrast, the sensitivity and specificity of the IgG immunoblot assay were 98 and 71%, respectively, with positive and negative predictive values of 87 and 96%, respectively. Therefore, the IgG immunoblot assay proved to be a sensitive and useful, noninvasive test for the diagnosis of H. pylori infection.

How does Helicobacter pylori cause mucosal damage? Its effect on acid and gastrin physiology

Helicobacter pylori infection increases gastric acid secretion in patients with duodenal ulcers but diminishes acid output in patients with gastric cancer and their relatives. Investigation of the basic mechanisms may show how H. pylori causes different diseases in different persons. Infection of the gastric antrum increases gastrin release. Certain cytokines released in H. pylori gastritis, such as tumor necrosis factor alpha and specific products of H. pylori, such as ammonia, release gastrin from G cells and might be responsible. The infection also diminishes mucosal expression of somatostatin. Exposure of canine D cells to tumor necrosis factor alpha in vitro reproduces this effect. These changes in gastrin and somatostatin increase acid secretion and lead to duodenal ulceration. But the acid response depends on the state of the gastric corpus mucosa. The net effect of corpus gastritis is to decrease acid secretion. Specific products of H. pylori inhibit parietal cells. Also, interleukin 1 beta, which is overexpressed in H. pylori gastritis, inhibits both parietal cells and histamine release from enterochromaffin-like cells. H. pylori also promotes gastric atrophy, leading to loss of parietal cells. Factors such as a high-salt diet and a lack of dietary antioxidants, which also increase corpus gastritis and atrophy, may protect against duodenal ulcers by decreasing acid output. However, the resulting increase of intragastric pH may predispose to gastric cancer by allowing other bacteria to persist and produce carcinogens in the stomach.

No additional value of bismuth subcitrate to combination omeprazole/amoxicillin therapy in the eradication of Helicobacter pylori

BACKGROUND

We investigated whether addition of bismuth subcitrate (BSC, 4 x 120 mg) to a two week therapy scheme of omeprazole (OME, 2 x 40 mg)/amoxicillin (AMO, 4 x 500 mg) increases Helicobacter pylori eradication.

MATERIALS AND METHODS

Patients with dyspepsia underwent upper endoscopy. H. pylori positive patients were randomized to treatment A (OME/AMO, 83 patients) or treatment B (OME/AMO/BSC, 84 patients).

RESULTS

In 65 patients of group A (78%) H. pylori was eradicated as determined from the histological assessment (Sydney classification) of antrum and corpus biopsies. In comparison, in 68 patients of group B (81%) H. pylori was eradicated (p = NS between groups). H. pylori eradication in both groups was associated similarly with a decrease of inflammation and activity whereas atrophy and intestinal metaplasia were not affected. A positive association was revealed between the decrease of H. pylori score and the decrease of both inflammation and activity scores for antrum as well as corpus biopsies.

CONCLUSIONS

Addition of BSC to OME/AMO does not increase H. pylori eradication in patients with dyspepsia. Eradication of H. pylori is associated with disappearance of epithelial damage (inflammation and activity) in antral and corpus mucosa.

What remaining questions regarding Helicobacter pylori and associated diseases should be addressed by future research? View from the Far East

Based on the findings of several epidemiological studies, it is believed that Helicobacter pylori infection is closely associated with gastric cancer. Because some abnormalities, such as severe inflammation in the gastric mucosa, impaired secretion of vitamin C, and increased gastric cell proliferation, improve after cure of the infection, anti-H. pylori therapy may reduce the incidence of gastric cancer. In Japan, the odds ratios for the development of atrophic gastritis and gastric cancer in H. pylori-positive patients are not as high as those reported in Europe and the United States. These findings suggest that factors other than H. pylori may exert a considerable influence on the development of atrophic gastritis and gastric cancer in Japan. It is not known whether atrophy and intestinal metaplasia, possible precursors of gastric cancer, are reversible. H. pylori infection is associated with a "gastritis, intestinal metaplasia, and gastric cancer sequence," but it remains obscure whether the infection is directly associated with the development of gastric cancer. We do not know which age group of patients should be given anti-H. pylori therapy for the prevention of gastric cancer. To elucidate whether the eradication of H. pylori can prevent gastric cancer, a Japanese intervention trial is now in progress.

Epstein-Barr virus infection in non-carcinomatous gastric epithelium

Gastric tissue specimens from 20 patients with chronic atrophic gastritis, one of whom also had an early gastric carcinoma, were studied for evidence of Epstein-Barr virus (EBV) infection by Southern blot analysis, DNA and RNA in situ hybridization, and immunohistochemistry for the presence of the EBV-determined nuclear antigen 1 (EBNA-1) and the latent membrane protein 1 (LMP-1). EBV DNA was detected in two cases with chronic atrophic gastritis and in the case with early gastric carcinoma by Southern blot hybridization. DNA in situ hybridization showed EBV genomes in the epithelial cells of two other cases with chronic atrophic gastritis and in non-carcinomatous and carcinomatous epithelial cells of the early gastric carcinoma case. EBNA-1 was detected in all cases. LMP-1 was detected in areas of intestinal metaplasia in eight patients with chronic atrophic gastritis. EBV-encoded small RNA 1 (EBER-1) expression was limited to carcinoma cells. These results show that gastric epithelium is frequently infected with EBV and suggest that prolonged EBV persistence may contribute to the development of gastric carcinoma.

IgG and IgA antibodies in Helicobacter pylori infections

We compared Helicobacter pylori-specific IgG and IgA antibodies in serum, salivary and gastric juice of H. pylori-infected and noninfected patients using the ELISA method. Serum and salivary anti-H. pylori IgG and IgA titres were higher in H. pylori-positive than H. pylori-negative patients. Serum H. pylori IgG titres were higher than those of serum-specific IgA. In contrast, H. pylori IgA titres in saliva samples were higher than those of specific IgG. In all patients, the levels of IgG antibodies were very low in gastric juice. H. pylori-positive patients with increased levels of IgA in sera, also exhibited increased IgA levels in gastric juice. The determination of IgA antibodies in serum and saliva may be used as a test that complements the IgG antibody assay.

Lifestyle and anti-Helicobacter pylori immunoglobulin G antibody among outpatients

Since eradication of Helicobacter pylori (H. pylori) is thought to be a preventive measure against stomach cancer, several studies have examined factors associated with the infection. This paper reports the association of the infection with lifestyle factors observed in a hospital-based case-control study. Cases were 140 anti-H. pylori IgG antibody-positive outpatients (75 males and 65 females). Controls were 52 antibody-negative outpatients (22 males and 30 females). Both groups had undergone gastroscopy at Aichi Cancer Center Hospital between February 1995 and February 1997, and lifestyle data collected on the first visit were linked to calculate odds ratios. A strong association was observed with smoking among males; age-adjusted odds ratio (OR) = 7.85, 95% confidence interval (CI), 2.03-30.4. Rice breakfast (OR = 3.74; 95% CI, 1.30-10.8) and soybean paste soup (every day vs. occasionally, OR = 5.24; 95% CI, 1.80-15.2) were also associated with antibody positivity in males, but not in females. In females, pickled Chinese cabbage (> or = 1/week vs. < or = 3/month, OR = 2.82; 95% CI, 1.06-7.48) and lettuce (> or = 1/week vs. < or = 3/month, OR = 2.90; 95% CI, 1.09-7.76) were significantly associated with positivity. Multivariate analysis gave similar estimates for the above factors. Although the association between smoking and H. pylori infection has not been detected in past studies of a general population, except one recent one, this study on outpatients suggested a possible association. Smoking may work as a cofactor disturbing incidental eradication of H. pylori by antibacterial agents administered for other reasons.

Gastric cancer distal to the cardia--prevention or cure?

Adenocarcinoma of the stomach distal to the cardia remains one of the most common cancers in the world. The interest in the aetiology of this disease has been rekindled because of recent epidemiological and molecular studies linking this cancer to H. pylori and certain dietary factors. The authors provide an updated review of the aetiology of gastric cancer. This review seeks to summarize the disease, to propose pathways of carcinogenesis and to suggest ways in which the "traditional" risk factors may be interpreted on the basis of evolving knowledge.

Long-term semi-quantitative follow-up of Helicobacter pylori associated gastritis

Helicobacter pylori infection has been implicated with the development of gastric carcinoma and lymphoma. We studied the long-term effects of H. pylori infection on gastric mucosa. Ten patients with Helicobacter pylori infection underwent repeat endoscopy and antral biopsies 8 years later. Gastric mucosal features (polymorphs, monocytes, intestinal metaplasia, atrophy and lymphoid aggregates) were graded from mild to severe (0 to 3) based on the Sydney system of gastritis classification. At repeat biopsy, 1 patient was negative for H. pylori after eradication therapy. Two patients (20 per cent) had spontaneous disappearance of H. pylori. One of these had intestinal metaplasia which progressed to low grade dysplasia. Polymorphs decreased with eradication of H. pylori (P < 0.05). Lymphoid aggregates increased with continued H. pylori infection but decreased with eradication of H. pylori (P < 0.05). Monocytes, intestinal metaplasia and atrophy remained unchanged. Persistent H. pylori infection appears to increase lymphoid aggregates and may promote its evolution into gastric lymphoma while eradication of H. pylori may result in a reduction of polymorphs and lymphoid aggregates.

Helicobacter pylori infection and atrophic gastritis. A case-control study in a rural town of Japan

We enrolled five hundred twenty-one patients with atrophic gastritis and 769 controls in a case-control study of atrophic gastritis and Helicobacter pylori infection and lifestyle factors. The participants had no history of upper gastrointestinal surgery. They were selected from 1,395 adult (35 years or older) residents of a rural town in Kyoto prefecture who participated in an annual health examination in 1987. Atrophic gastritis was diagnosed on the basis of serum pepsinogen levels: pepsinogen I levels (< or = 70 ng/ml) and pepsinogen I/pepsinogen II ratios (< or = 3.0). The presence of immunoglobulin G antibodies to H. pylori indicated H. pylori infection. At the time of the health examination, participants were interviewed about daily lifestyle habits such as use of cigarettes and alcoholic beverages and consumption of green-yellow vegetables. Unconditional logistic regression analysis indicated that H. pylori infection was associated with a significantly increased risk for atrophic gastritis for all participants (odds ratio, 8.17; 95% confidence interval, 5.63-11.84); for men (odds ratio, 10.91; 95% CI, 5.25-22.67); and for women (odds ratio, 7.28; 95% CI, 4.72-11.22). We found no statistically significant relations between lifestyle factors and atrophic gastritis.

Seroprevalence and epidemiology of Helicobacter pylori infection in patients with cirrhosis

BACKGROUND

Helicobacter pylori infection is the major pathogenic factor for peptic ulcer disease. Its epidemiology is not fully known; few data are available in patients with chronic liver disease.

AIMS

To investigate the seroprevalence and factors associated with Helicobacter pylori infection in a series of liver cirrhosis patients.

METHODS

Two hundred and twenty consecutive patients were prospectively included in a study aimed to evaluate the effect of dietary intervention on cirrhosis complications and survival. At inclusion, an epidemiological and clinical questionnaire was completed. Sera were obtained and stored at -70 degrees C until analyzed. They were tested for Helicobacter pylori antibodies using a commercial ELISA kit.

RESULTS

Eleven out of 220 patients had borderline anti-Helicobacter pylori IgG titers. Of the remaining 209 patients, 105 (50.2%) showed positive titers of Helicobacter pylori IgG. Univariate analysis showed that Helicobacter pylori infection was more frequent in older patients, those born outside Catalonia, and in patients with a low educational level. Past ethanol consumption and current smoking correlated negatively with Helicobacter pylori infection. Multivariate analysis selected age (OR 3.1. 95% CI 1.46-6.45), educational level (OR 2.2. 95% CI 1.18-4.2) and alcohol consumption (OR 0.7. 95% CI 0.45-0.99) as the variables independently related to Helicobacter pylori infection.

CONCLUSIONS

Helicobacter pylori infection in cirrhosis has the same epidemiological pattern as in the general population. Suggestions that the etiology or the severity of the liver disease could be related to Helicobacter pylori infection were not confirmed by our study.

Atrophic body gastritis: distinct features associated with Helicobacter pylori infection

BACKGROUND

Usually, atrophic body gastritis has been considered an autoimmune disease characterized by the presence of parietal cell antibodies. Previous investigations into the role of Helicobacter pylori infection have obtained conflicting results. The aim of this study was to investigate the prevalence and role of H. pylori in a prospectively investigated population of patients with corpus-predominant atrophic gastritis.

PATIENTS AND METHODS

A consecutive series of 67 newly diagnosed cases of atrophic body gastritis was derived from a screening of 326 patients with unexplained anemia or dyspepsia. Criteria for diagnosis were fasting hypergastrinemia, pentagastrin-resistant achlorhydria, and histological confirmation of body atrophy. In all 67 patients, H. pylori infection was evaluated independently by histological assay and urease test. The gastritis status of both the fundic and antral mucosa were graded according to the Sydney system. Parietal cell and intrinsic factor antibodies also were determined.

RESULTS

Active H. pylori infection was present in 26.8% of our patients and allowed us to identify a patient's subpopulation with a significantly smaller degree of body mucosa damage as shown by functional parameters (gastrin, gastric acid secretion, pepsinogen I) and histological assessment. In this subpopulation, a higher prevalence of gastric cancer familial history was found. Presence of parietal cell antibodies showed a similar prevalence in H. pylori-positive and H. pylori-negative patients (61.1% vs. 69.4%) and was not associated with significant functional and histological differences. Cure of infection determined an evident improvement of corporal atrophy as well as a reduction of hypergastrinemia.

CONCLUSION

Active H. pylori infection, a potential cause of oxyntic gland atrophy, is found in one-fourth of patients with newly diagnosed atrophic body gastritis.

Helicobacter pylori infection accelerates gene expression of glicentin in the gastric mucosa. Its association with intestinal metaplasia of the stomach

BACKGROUND

Glicentin is an intestinal polypeptide hormone which seems to promote intestinal metaplasia (IM) in the gastric mucosa. The aim of this study was to clarify whether Helicobacter pylori infection accelerates glicentin gene expression.

METHOD

Glicentin mRNA was investigated by reverse-transcription polymerase chain reaction using gastric biopsies from 47 patients examined endoscopically and denying IM.

RESULTS

IM was observed in 18 (38.3%) cases histologically, but not in the other 29 (62.7%). Glicentin mRNA was significantly correlated with histological IM (P < 0.01) and was positively correlated with H. pylori infection (P < 0.05).

CONCLUSION

Our results indicate that H. pylori infection is associated with the induction of glicentin in the gastric mucosa, thus supporting the hypothesis that H. pylori infection accelerates IM of the stomach.

High prevalence of the CagA-positive Helicobacter pylori strains in Japanese asymptomatic patients and gastric cancer patients

BACKGROUND

Several studies have shown that infection of Helicobacter pylori strains possessing cagA is associated with atrophic gastritis and gastric cancers.

METHOD

In 58 pairs of early gastric cancer patients and sex- and age-matched controls, isolated H. pylori strains were tested for possession of cagA. The presence of atrophic gastritis was also examined.

RESULTS

Proportions of cagA-positive strains were 100% in cancer patients and 92.3% in controls. Atrophic gastritis was seen in 96.7% and 95.8% of cancer and control patients in whom cagA-positive strains (NS) were detected. However, it was seen in only 20% of H. pylori-negative control patients (P < 0.01).

CONCLUSIONS

The present results do not suggest any specific association between cagA-positive strains and gastric cancer. However, frequent prevalence of cagA-positive strains might be associated with the high incidence of atrophic gastritis in Japanese populations.

Capsaicin as an inhibitor of the growth of the gastric pathogen Helicobacter pylori

Capsaicin, the active ingredient in chili, has been implicated as both a cytoprotective and a detrimental agent to the gastric mucosa. The effect of capsaicin on Helicobacter pylori has not been investigated previously. Therefore, we performed in vitro time- and concentration-dependent studies to examine the growth of H. pylori in the presence of capsaicin. Capsaicin specifically inhibited growth of H. pylori dose-dependently at concentrations greater than 10 micrograms ml-1 (P < 0.05) but did not inhibit the growth of a human fecal commensal Escherichia coli strain. Bactericidal activity was observed within 4 h. Capsaicin continued to exhibit bactericidal activity when incubated at pH values as low as 5.4. Ingestion of chili, therefore, could have a protective effect against H. pylori-associated gastroduodenal disease. This effect deserves further study in animal models.

Eradication of Helicobacter pylori in patients with end-stage renal disease under dialysis treatment

The efficacy and safety of combination therapy with amoxicillin, lansoprazole, and plaunotol for the eradication of Helicobacter pylori in patients on dialysis were evaluated. The study subjects comprised 15 dialysis patients in whom H pylori had been found in the gastric mucosa. The patients were given 500 mg amoxicillin once a day for 3 weeks, 30 mg lansoprazole once a day for 8 weeks, and 80 mg plaunotol three times a day for 24 weeks. Endoscopy was performed on entry and at 4 and 24 weeks after cessation of amoxicillin. The concentrations of serum gastrin and gastric juice ammonia also were measured. Fourteen patients completed the treatment protocol, one having dropped out because of nausea and diarrhea. H pylori was eradicated in 11 of the 14 patients 4 weeks after the end of amoxicillin therapy (eradication rate, 78.6%). All but one patient was free of H pylori 24 weeks after the amoxicillin was discontinued. Patients who became negative for H pylori had significantly decreased serum gastrin and gastric juice ammonia concentrations. Our findings indicate that a combination of amoxicillin, lansoprazole, and plaunotol can be used to eradicate H pylori in patients on dialysis.

Helicobacter pylori and atrophic gastritis

Infection with Helicobacter pylori plays a crucial role in the etiology of atrophic gastritis and gastric cancer. Studies suggest a nine-fold increased risk for both conditions in the presence of infection. The risk of atrophic gastritis in the presence of infection is dependent upon the severity of the gastritis. Gastritis is increased in subjects infected with a cytotoxic H pylori strain and in those with a decreased acid production. The development of atrophy may be related to the induction of cross-reacting antibodies recognizing Lewis epitopes on H pylori lipopolysaccharide and gastric mucosa. Future studies have to demonstrate whether atrophic gastritis and gastric cancer can be prevented by early H pylori eradication.

Chronic sequelae of foodborne disease

In the past decade the complexity of foodborne pathogens, as well as their adaptability and ability to cause acute illness, and in some cases chronic (secondary) complications, have been newly appreciated. This overview examines long-term consequences of foodborne infections and intoxications to emphasize the need for more research and education.

Evaluation of eight enzyme immunoassays for detection of immunoglobulin G against Helicobacter pylori

Eight commercial enzyme-linked immunosorbent assays (ELISAs) were used to test sera taken from 102 patients in whom Helicobacter pylori infection status had been determined by means of biopsy culture, PCR, histology, and urease production and by 13C urea breath test. By those means, 61 patients had been found to be infected. Assays were compared by receiver operating characteristic analysis. Sensitivities ranged from 86 to 98%; specificities ranged from 83 to 98%. In a group consisting of the assays by Bio-Whittaker, Meddens Biotech, Orion (Pyloriset EIA G, new version), and Enteric Products, Inc. (HM Cap), differences in performance were not statistically significant. Sensitivities in this group ranged from 93 to 98%; specificities ranged from 95 to 98%. Assays from this group may be useful in addition to biopsy-based methods in diagnosing H. pylori infection.

Ornithine decarboxylase activity is a marker of premalignancy in longstanding Helicobacter pylori infection

BACKGROUND

Longstanding Helicobacter pylori infection may increase the risk of developing gastric adenocarcinoma. The sequence of chronic active gastritis leading to gastritis with atrophy and subsequent intestinal metaplasia is thought to be a key step in gastric carcinogenesis. Ornithine decarboxylase (ODC) activity is increased in some pre-malignant gastrointestinal conditions and is essential for malignant transformation in vitro.

AIMS

To measure ODC activity in the antrum of H pylori infected and non-infected subjects and to relate this to histological abnormalities associated with recent and longstanding H pylori infection.

METHODS

Six antral mucosal biopsy specimens were obtained from 75 patients for detailed histological assessment and measurement of ODC activity. Samples were measured in duplicate and results expressed as median, interquartile range in pmol/mg protein/h.

RESULTS

ODC activity was significantly higher in H pylori positive (164, 88-259 pmol/mg/h) than H pylori negative subjects (99.8, 55-158 pmol/mg/h, p = 0.003). However the presence of gastritis, irrespective of the severity of inflammation or activity had no influence on ODC activity. Gastritis with atrophy was associated with increased ODC activity, which was closely related to the severity of the atrophy (p = 0.01). Similarly, ODC activity was significantly increased in subjects with intestinal metaplasia (196, 83-25) compared with those without intestinal metaplasia (111.7, 65-175, p < 0.04).

CONCLUSIONS

These results indicate that the histological changes associated with longstanding H pylori infection rather than inflammation alone are associated with increased polyamine biosynthetic activity. This may be relevant to H pylori associated gastric carcinogenesis.

Helicobacter pylori infection in non-ulcer dyspeptic and ulcer patients. Determinants and consequences in 'real life'

BACKGROUND

Infection rates are high in patients with ulcer disease, but even non-ulcer dyspepsia (NUD) patients have Helicobacter pylori infection. The Notodden Helicobacter study is an 'outcome study' of clinical practice in a local hospital. The study may identify factors associated with infection and evaluate whether H. pylori infection predicts symptoms in both ulcer disease and NUD.

METHODS

Base-line results on infection, symptoms, endoscopy, and treatment were registered in 587 ulcer and NUD patients. H. pylori status was assessed with a rapid urease test. Questionnaire data (5-43 months after treatment) give information about symptoms. Regression models to identify H. pylori status were developed.

RESULTS

Ulcer patients (H. pylori +/-) were similar to infected NUD patients. In contrast, uninfected NUD patients were younger, had less severe symptoms, and used less medication than other patients. In NUD, infection rate increased with epigastric pain, male sex, and age.

CONCLUSION

From a local hospital's point of view, H. pylori-infected NUD patients are like ulcer patients with regard to symptoms and demographics. The results suggest that H. pylori infection may give dyspeptic symptoms through other mechanisms than ulcer. We propose a division of the NUD group into HINUD (Helicobacter-infected NUD) and NINUD (non-infected NUD).

High seroprevalence of IgG against Helicobacter pylori among endoscopists in Taiwan

A prospective survey to investigate the seroprevalence of IgG against Helicobacter pylori among endoscopists in Taiwan was conducted by analyzing blood samples of 70 study subjects and 64 nonendoscopist physicians with quantitative ELISA. Personal information and the practices of infection control related to gastroscopy examination were obtained by a self-administered questionnaire. Significant differences were detected in the IgG prevalence between study and control subjects (80.0% vs 51.6%; P < 0.05). The serum level of antibody in endoscopists (385.2 +/- 36.1 unit/ml) was significantly higher than that of nonedoscopists (211.8 +/- 33.0 unit/ml; P = 0.018). Endoscopists performing 30 or more sessions of gastroscopy per week had higher seroprevalence than those performing less than 30 sessions (90.9% vs 70.3%; P = 0.0126). In conclusion, endoscopists in Taiwan had a high prevalence of H. pylori infection. The cause might be related to the frequency of gastroscopies performed.

The risk of stomach cancer in patients with gastric or duodenal ulcer disease

BACKGROUND

Helicobacter pylori infection, now considered to be a cause of gastric cancer, is also strongly associated with gastric and duodenal ulcer disease. The discovery of these relations has brought the long-controversial connection between peptic ulcers and gastric cancer into focus.

METHODS

We estimated the risk of stomach cancer in a large cohort of hospitalized patients with gastric or duodenal ulcers, as recorded in the Swedish Inpatient Register between 1965 and 1983. Altogether, 57,936 patients were followed through 1989, for an average of 9.1 years. The standardized incidence ratio--the ratio of the observed number of cancers to the number expected on the basis of the incidence in the Swedish population at large--was used as a measure of relative risk.

RESULTS

After peaking in the first 3 years of follow-up, the standardized incidence ratio for gastric cancer among 29,287 patients with gastric ulcers leveled off at 1.8 (95 percent confidence interval, 1.6 to 2.0) and remained significantly increased throughout follow-up, which was as long as 24 years for some patients. Prepyloric ulcer, diagnosed in 8646 patients, was not associated with a significant excess risk (standardized incidence ratio, 1.2; 95 percent confidence interval, 0.8 to 1.6). In the cohort of patients with duodenal ulcers (24,456 patients), the incidence of gastric cancer was significantly lower than expected. After the second year of follow-up, the standardized incidence ratio was only 0.6 (95 percent confidence interval, 0.4 to 0.7) and remained stable thereafter.

CONCLUSIONS

Gastric ulcer disease and gastric cancer have etiologic factors in common. A likely cause of both is atrophic gastritis induced by H. pylori. By contrast, there appear to be factors associated with duodenal ulcer disease that protect against gastric cancer.

Long-term follow-up of gastric histology after Helicobacter pylori eradication

Helicobacter pylori causes chronic active gastritis and is thought to be associated with the development of gastric atrophy, intestinal metaplasia and carcinoma. As the effect of H. pylori eradication on this process is poorly understood, we sought to determine the long-term effects of H. pylori eradication on gastric histology. Fifty-four patients with duodenal ulceration associated with H. pylori infection received H. pylori eradication therapy in 1985/86 and either remained infected (n = 22) or had the infection eradicated (n = 32); patients were followed up by endoscopy with gastric antral biopsy for 7.1 years (mean). Histopathological analysis of gastric antral mucosa from patients rendered H. pylori-negative revealed a marked decrease in both inflammatory cells within the lamina propria and intraepithelial neutrophils and an increase in epithelial mucinogenesis. Gland atrophy remained unchanged in both H. pylori-positive and -negative patients. When examined for the presence and severity of intestinal metaplasia, there was neither a difference between the two patient groups nor a change with time. These data demonstrate that significant long-term improvements in gastric histology accompany H. pylori eradication when compared with histology in patients with persistent infection. Whether this confers a protective effect by reducing the risk of gastric carcinoma remains unknown.

Long-term course and consequences of Helicobacter pylori gastritis. Results of a 32-year follow-up study

BACKGROUND

The long-term course of Helicobacter pylori gastritis is not well known because there are few follow-up studies available, and the follow-up time has been short.

METHODS

The progression of H. pylori infection and chronic gastritis was retrospectively examined in 102 patients followed up for 32 years. In all patients a blind suction biopsy from the corpus mucosa was taken in 1952, and an endoscopic re-examination with biopsy specimens from the antrum and corpus was performed in 1983.

RESULTS

In the first examination 85 patients (83%) were H. pylori-positive as assessed from Giemsa-stained corpus mucosa specimens as compared with 70 H. pylori-positive patients (69%) at the end of the follow-up (1983). Two of the 17 patients who were initially H. pylori-negative became positive in 1983, implying an infection rate of 0.4% per patient-year. On the other hand, 17 of the 85 patients who were initially H. pylori-positive became negative in 1983, representing a disappearance rate of 0.6%. However, the stomach became completely normal in only eight cases, which represents a healing rate of 0.3% per patient-year. All patients with duodenal ulcer disease were H. pylori-positive at the first examination and remained so during the follow-up. In these patients chronic gastritis affected predominantly the antral mucosa, and corpus atrophy did not develop. Parietal cell antibodies appeared during the follow-up in six cases, and five of them were H. pylori-positive at the first examination. In most of these cases gastritis progressed into severe grades of corpus atrophy accompanied by the disappearance of H. pylori infection and normalization of the antral mucosa.

CONCLUSIONS

New H. pylori infection and complete healing of infected mucosa may occur in adult life, but this is rare. Duodenal ulcer disease is associated with persistent H. pylori infection and absence of corpus atrophy. The appearance of parietal cell antibodies leads to progression of corpus atrophy and disappearance of H. pylori.

Clinical expressions of Helicobacter pylori infection

Helicobacter pylori infection is very common both in the United States and internationally. However, clinical manifestations of this infection vary markedly among different individuals. Apart from gastritis, which may be asymptomatic, patients may develop peptic ulceration or a gastric neoplasm. However, these patients represent a minority of patients infected with H. pylori. This article aims to review the different possible consequences of H. pylori infection.

Atrophic gastritis and Helicobacter pylori infection in patients with reflux esophagitis treated with omeprazole or fundoplication

BACKGROUND

Helicobacter pylori infection plays an important part in the development of atrophic gastritis and intestinal metaplasia, conditions that predispose patients gastric cancer. Profound suppression of gastric acid is associated with increased severity of gastritis caused by H. pylori, but it is not known whether acid suppression increases the risk of atrophic gastritis.

METHODS

We studied patients from two separate cohorts who were being treated for reflux esophagitis: 72 patients treated with fundoplication in Sweden and 105 treated with omeprazole (20 to 40 mg once daily) in the Netherlands. In both cohorts, the patients were followed for an average of five years (range, three to eight). After fundoplication, the patients did not receive acid-suppressive therapy. The presence of H. pylori was assessed at the first visit by histologic evaluation in the fundoplication group and by histologic and serologic evaluation in the omeprazole group. The patients were not treated for H. pylori infection. Before treatment and during follow-up, the patients underwent repeated gastroscopy, with biopsy sampling for histologic evaluation.

RESULTS

Among the patients treated with fundoplication, atrophic gastritis did not develop in any of the 31 who were infected with H. pylori at base line or the 41 who were not infected; 1 patient infected with H. pylori had atrophic gastritis before treatment that persisted after treatment. Among the patients treated with omeprazole, none of whom had atrophic gastritis at base line, atrophic gastritis developed in 18 of the 59 infected with H. pylori(P<0.001) and 2 of the 46 who were not infected (P=0.62).

CONCLUSIONS

Patients with reflux esophagitis and H. pylori infection who are treated with omeprazole are at increased risk of atrophic gastritis.

Antigastric autoantibodies in Helicobacter pylori gastritis: prevalence, in-situ binding sites and clues for clinical relevance

Colonization of human gastric mucosa with Helicobacter pylori leads to chronic active gastritis and induces the occurrence of an acquired mucosa-associated lymphoid tissue (MALT) in the stomach. This remodelling of the gastric mucosa together with chronic antigen persistence may induce autoimmune reactions. The aim of this study was to investigate humoral autoimmune reactions to human gastric mucosa in H. pylori gastritis and their clinical relevance. Sera from patients with dyspeptic symptoms were tested for presence of IgG immunoglobulins against H. pylori. Gastric infection with H. pylori and alterations of gastric mucosa were demonstrated by histological examination of gastric biopsy specimens. All sera were tested for reactivity against human gastric mucosa by immunohistochemistry. Two different in-situ binding sites of antigastric autoantibodies were observed. Binding to canalicular structures within parietal cells was significantly correlated with antibodies to H. pylori, elevated basal gastrin levels and atrophy of gastric corpus glands. Our data indicate that autoimmune reactions to antigens in the human gastric mucosa occur in H. pylori gastritis and that they may play a role in the pathogenesis of the disease.

The role of Helicobacter pylori in pathogenesis: the spectrum of clinical outcomes

Helicobacter pylori is probably the commonest bacterial infection worldwide and is now accepted as the cause of chronic active type B gastritis. Most patients continue through life with a chronic superficial gastritis while some develop either duodenal or gastric ulcer. In a very small proportion the lymphoid reaction to H. pylori infection appears to progress to become a mucosal associated lymphoid tissue (MALT) lymphoma, while in others the evidence suggests that chronic superficial gastritis progresses to atrophy, the loss of gastric acid secretory capacity and the development of gastric cancer. The mechanisms involving H. pylori infection in peptic ulceration are increasingly well understood and H. pylori is now accepted as having a critical role in duodenal ulcer, where the prevalence of infection is 90 to 95%. More important is the dramatic reduction in duodenal ulcer recurrence after successful eradication of the organism to about 4% in a year compared to recurrences of up to 80% in those who ulcers have been healed but in whom the infection persists. There is also increasing evidence for the involvement of H. pylori in gastric ulcer, where infection is seen in between 60 and 80%, and there is a similar dramatic reduction in recurrence following cure of H. pylori infection. The progression of H. pylori gastritis from the acute infection to chronic superficial gastritis, predominantly antral gastritis or a pangastritis with increasing atrophy appears to be associated with the differing outcomes seen in this disease. Moreover, there is increasing data on the roles played by bacterial heterogeneity and the virulence of the organism, host factors such as the HLA genotype and immune response, environmental factors and the age of acquisition of infection play in determining these clinical outcomes of the disease.

Helicobacter pylori and gastric carcinogenesis

BACKGROUND

Helicobacter pylori causes chronic persistent gastritis in virtually all infected subjects, leading to development of atrophic gastritis, intestinal metaplasia and eventually dysplasia and gastric cancer in a number of infected subjects. Based on the available evidence, an IARC monograph committee classified H. pylori as a class I carcinogen to humans. Prospective studies suggest that infection increases the risk for atrophic gastritis and gastric cancer at least 8-fold. In the presence of infection, the risk for atrophy and cancer seems higher if a subject becomes infected in early childhood, if infection occurs with a cagA positive strain, and if acid output is decreased.

CONCLUSION

H.pylori is a gastric carcinogen. The clinical implications and possible strategies for cancer prevention have to be delineated in the near future.

Helicobacter pylori as a risk factor for cancer

In 1985, gastric cancer was the second most common cause of cancer death in the world. The rapid decline in gastric cancer rates over the last few decades has been attributed to a decline in the prevalence of environmental risk factors for gastric cancer and/or an increase in the prevalence of protective factors. One such risk factor could be the bacterium Helicobacter pylori. Epidemiological studies have shown that areas with high gastric cancer rates often have a correspondingly high prevalence of H. pylori and prospective studies have shown that subjects with serological evidence of H. pylori infection were significantly more likely to go on to develop gastric cancer than those who did not. Helicobacter pylori itself does not appear to be either genotoxic or mutagenic. Infection is, however, associated with increased cell turnover, a chronic immune response accompanied by increased levels of reactive oxygen metabolites and a reduction in gastric levels of ascorbic acid, all conditions that could favour the development of cancer. Nonetheless, the majority of those who are infected with H. pylori do not go on to develop gastric cancer and other factors, such as the strain of the infecting organism or consumption of dietary antioxidants including vitamin C, could also affect the risk of cancer. Finally, it has been estimated that more than one third, and possibly as many as 90% of gastric cancers might be attributable to infection with H. pylori. Prevention and treatment of infection are, therefore, possible approaches to reducing gastric cancer rates. It is, however, unclear what, if any, effect eradication of the infection would have on an individual's risk of gastric cancer and, to date, anti-Helicobacter therapy has only been shown to be of potential benefit in the treatment of low grade gastric MALT lymphomas.