Review article: the development of atrophic gastritis--Helicobacter pylori and the effects of acid suppressive therapy

Helicobacter pylori is uniquely adapted to survival in the strongly acidic gastric lumen. In vitro, both acid and certain acid suppressors affect bacterial growth. In vivo, there is little evidence that acid suppressors have any effect on bacterial survival. In contrast, decrease of acid secretion quickly leads to a spreading of the bacterial infection throughout the body and fundus of the stomach, which is accompanied by an increase of the associated gastritis. Helicobacter pylori gastritis may, in a substantial number of infected subjects, ultimately lead to atrophy and intestinal metaplasia, conditions with an increased risk for gastric cancer. This review summarizes the data on the interrelation between Helicobacter pylori, gastric acid secretion and development of atrophic gastritis.     

Prevalence of Helicobacter pylori infection and gastric mucosal abnormalities in chronic pancreatitis

OBJECTIVE: Chronic pancreatitis is often associated with abnormal gastric acid secretion. However, previous studies have taken into consideration neither the potential role of Helicobacter pylori (H. pylori) infection nor histological features of the gastric mucosa in this context. The aim of this study was to analyze the prevalence of H. pylori infection as well as the pattern of gastritis in patients with chronic pancreatitis. METHODS: Forty patients with chronic alcoholic pancreatitis were included in the study: 40 patients with alcoholic liver cirrhosis and normal exocrine pancreatic function and 40 asymptomatic nonalcoholic subjects matched for age and sex used as control subjects. Endoscopy was performed in all patients, and five biopsy specimens from the antrum (three from the gastric body and two from the cardia) were taken for histological grading of gastritis and H. pylori assessment. RESULTS: Prevalence of H. pylori infection was similar in subjects with chronic pancreatitis (38%), asymptomatic subjects (28%) and liver cirrhosis (30%). Topography and expression of H. pylori-associated chronic gastritis was also not different among the three groups of subjects. In H. pylori-negative subjects, the presence of moderate to severe chronic antral gastritis was significantly more common in patients with chronic pancreatitis (40%) than in subjects with liver cirrhosis (18%) and in asymptomatic subjects (14%) (p < 0.05). No difference was found among the three groups of patients with regard to gastritis activity, atrophy, and intestinal metaplasia in the various gastric regions. The chronicity grade of gastritis did not correlate with the severity of pancreatic insufficiency. CONCLUSION: Prevalence of H. pylori infection is not different in patients with chronic pancreatitis as compared with subjects alcoholic liver cirrhosis and asymptomatic subjects. A severe H. pylori-negative chronic gastritis is more common in patients with chronic pancreatitis. This chronic inflammation of the gastric mucosa could contribute to determining the changes in gastric physiology described in patients with chronic pancreatitis.     

Duodenal ulcer, Helicobacter pylori, and gastric secretion

Patients with chronic dyspepsia were categorised by macroscopic appearance at oesophagogastroduodenoscopy as having duodenal ulceration (DU), other diagnosed lesions such as reflux oesophagitis, carcinoma of stomach, etc, or no organic lesion (non-ulcer dyspepsia, NUD). Material was collected to identify gastric infection with Helicobacter pylori (H pylori) by CP urease test, culture, and histological examination and to make the microscopic diagnosis of active chronic gastritis. Each patient in the DU and NUD categories was then invited to volunteer for a gastric secretion study in which maximal gastric secretion in response to histamine was measured. Sixty two gastric secretion tests were performed (31 DU, 31 NUD). The presence of H pylori was associated with active chronic gastritis (100%). DU patients secreted more acid than the NUD patients. H pylori positivity was associated with decreased maximal gastric secretion in both groups. There was a positive correlation between smoking and maximal acid output shown only in H pylori negative but not in H pylori positive patients. These findings were clear cut when all corrections of maximal gastric secretion were made for pyloric loss, duodenogastric reflux, and stature. This study failed to show any aetiological link between H pylori and DU by increased maximal gastric secretion.     

Urinary procoagulant activity and tissue factor levels in patients with diabetes mellitus

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 inhibits the secretory activity of gastric parietal cells in patients with chronic gastritis. An ultrastructural study

BACKGROUND: Previous in vitro studies suggested that Helicobacter pylori may inhibit the acid secretion of gastric parietal cells. The aim of this study was to investigate ultrastructurally the influence of H. pylori infection on the gastric parietal cell function in vivo. METHODS: This study comprised 28 patients with chronic gastritis. Biopsy specimens were taken from the gastric body in all cases and examined by electron microscopy. Gastric parietal cells were counted in each ultrathin section and classified into secretory and non-secretory types. The pH of the gastric juice was also measured in all patients. RESULTS: The number of parietal cells in the secretory phase was significantly lower in H. pylori-infected (n = 16) patients than in those (n = 12) without H. pylori infection. The intragastric pH was significantly higher in patients with H. pylori-associated gastritis than in those without H. pylori infection. Parietal cells in secretory phase tended to decrease in proportion to the activity of the gastric mucosal inflammation. CONCLUSIONS: The results of this investigation suggests that H. pylori-associated gastritis is related to a decreased secretory activity of the gastric parietal cells.     

Influence of Helicobacter pylori on gastric secretion. Study on variously associated gastric body, fundus and antrum chronic gastritis

Among the various themes related to Helicobacter pylori (HP) which is still a subject of discussion, there is the possible influence of this bacterium on gastric secretory physiology. In the present study, an evaluation has been carried out of stimulated gastrinemia, stimulated acid secretion and total peptic activity in gastric juice in the course of a paradigmatic condition, as autonomous chronic gastritis, in order to reveal possible modifications induced by the HP infection. In cases of HP positive chronic superficial antral gastritis associated either with normal body-fundic mucosa or with superficial gastritis, there is a significant increase of stimulated gastrinemia in comparison to HP negative groups and controls. In the course of body-fundic atrophic and preatrophic chronic gastritis associated either with antral superficial chronic gastritis or with antral atrophic gastritis, there are no statistically significant differences between HP positive and HP negative subjects. As regards acid and pepsin secretion no significant differences emerge in any group between HP positive and HP negative subjects. In the HP positive subjects with antral superficial gastritis and higher gastrin values the study of acid and pepsin secretion has yielded no significant variations. From the results of this study it emerges how gastric secretory parameters vary exclusively according to the histologic state of gastric mucosa. Therefore, the lesion action of HP may mainly be attributed to a direct action, rather than to substantial gastric secretory changes.     

Transplantation of hepatocytes for prevention of intracranial hypertension in pigs with ischemic liver failure

BACKGROUND: How Helicobacter pylori infection affects gastric acid secretion is still unclear. METHODS: Gastric juice pH, ammonia concentration in gastric juice, serum gastrin level, and grade of gastritis in accordance with the Sydney System were determined for patients with gastric ulcer (GU) and duodenal ulcer (DU) before and after treatment with lansoprazole and amoxicillin, and results were compared with those of H. pylori-negative controls. RESULTS: Scores for H. pylori density, atrophy, metaplasia, and activity of gastritis in the corpus were higher in patients with GU, especially those with proximally located GU, than in those with DU. Gastric juice pH was significantly higher in GU patients than in DU patients and controls. After H. pylori eradication, gastric juice pH and serum gastrin levels in both GU and DU patients were significantly decreased to control levels. In patients without eradication, no significant changes in these factors were observed. CONCLUSIONS: These findings suggest that H. pylori infection and gastritis in the corpus suppress acid secretion and increase gastric juice pH, resulting in hypergastrinemia, and that eradication of H. pylori normalizes acid secretion and serum gastrin levels.     

Cloning, genomic structure, and expression of mouse ring finger protein gene Znf179

OBJECTIVE: H. pylori causes chronic gastritis, which may progress to peptic ulcer, gastric atrophy, or gastric cancer. However, little is known about the role of H. pylori infection in reflux esophagitis and the relationship between reflux esophagitis and atrophic gastritis needs to be clarified. We sought to identify the possible interrelationships among Helicobacter pylori infection, reflux esophagitis, and atrophic gastritis, to signal areas in which researchers should consider focusing their attention. METHODS: A broad-based Medline search was performed to identify all related publications addressing H. pylori infection, atrophic gastritis, gastroesophageal reflux disease (GERD), secretion of gastric acid, and gastric motility published between 1966 and July 1997. RESULTS: Whereas some studies have shown no significant association between H. pylori infection and reflux esophagitis, others have observed that the prevalence of H. pylori infection was lower in patients with GERD, implying a protective role. Eradication of H. pylori leads to occurrence of reflux esophagitis in some cases, but the mechanisms inducing posteradication reflux esophagitis are unknown. H. pylori infection may lead to atrophic gastritis (and hence hypochlorhydia) through both bacterial and host factors, although gastric atrophy and subsequent intestinal metaplasia are hostile to H. pylori because of hypochlorhydria. Although it has been reported that long-term proton pump inhibitor therapy for refractory reflux esophagitis may induce or enhance the development of gastric atrophy in H. pylori-infected patients, this relationship has been disputed. CONCLUSIONS: H. pylori infection may be negatively associated with reflux esophagitis, but this requires confirmation. Research then needs to focus on whether this is explained through motility- or acid-related mechanisms. The potential costs of maintenance antireflux therapy may need to be taken into account when evaluating the cost effectiveness of anti-H. pylori therapy.     

Potential role of molecular mimicry between Helicobacter pylori lipopolysaccharide and host Lewis blood group antigens in autoimmunity

Helicobacter pylori is involved in gastritis, gastric and duodenal ulcers, gastric adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma. Earlier studies already suggested a role for autoimmune phenomena in H. pylori-linked disease. We now report that lipopolysaccharides (LPS) of H. pylori express Lewis y, Lewis x, and H type I blood group structures similar to those commonly occurring in gastric mucosa. Immunization of mice and rabbits with H. pylori cells or purified LPS induced an anti-Lewis x or y or anti-H type I response, yielding antibodies that bound human and murine gastric glandular tissue, granulocytes, adenocarcinoma, and mucosa-associated lymphoid tissue lymphoma cells. Experimental oral infections in mice or natural infection in humans yielded anti-Lewis antibodies also. The beta chain of gastric (H+,K+)-ATPase, the parietal cell proton pump involved in acid secretion, contained Lewis y epitopes; gastric mucin contained Lewis x and y antigenic determinants. Growth in mice of a hybridoma that secretes H. pylori-induced anti-Lewis y monoclonal antibodies resulted in histopathological evidence of gastritis, which indicates a direct pathogenic role for anti-Lewis antibodies. In conclusion, our observations demonstrate that molecular mimicry between H. pylori LPS and the host, based on Lewis antigens, and provide understanding of an autoimmune mechanism for H. pylori-associated type B gastritis.     

Consistent improvement in sphincterotome orientation with manual grooming

AIMS: To determine the prevalence of lymphoid follicles in Helicobacter pylori positive and negative gastritis in antral and body type gastric mucosa in patients with non-ulcer dyspepsia (NUD), duodenal ulcer, or gastric ulcer; to correlate follicle presence with patient age; to evaluate the correlation between the prevalence of lymphoid follicles and active and inactive gastritis and its severity; and to assess the positive predictive value of lymphoid follicle prevalence with respect to H pylori infection. METHODS: Gastric biopsy specimens, graded according to the Sydney system, from 337 patients were studied. RESULTS: Lymphoid follicles occurred more often in antral mucosa (78%) than in body type mucosa (41%) and were observed in 85% of patients with H pylori positive gastritis. There was no significant difference between NUD and gastric and duodenal ulcer disease with regard to the presence of lymphoid follicles. The positive predictive value of the presence of lymphoid follicles in H pylori infection was 96%. Lymphoid follicles were more commonly observed in patients aged between 10 and 29 years. Lymphoid follicles were more frequently found in pangastritis of all subtypes than in antral gastritis and also in active gastritis than in inactive gastritis. The presence of lymphoid follicles correlated strongly with the degree and severity of gastritis. CONCLUSION: Lymphoid follicles are a constant morphological feature of H pylori associated gastritis.     

Helicobacter pylori prevalence in acquired immunodeficiency syndrome

Helicobacter pylori is consistently reported with high prevalence in HIV-negative patients with chronic gastritis and active ulcer disease. This study is an evaluation of the prevalence of H. pylori in AIDS patients, and the association with chronic gastritis, erosions, and ulcer disease. Seventy-three AIDS patients referred for the evaluation of gastrointestinal symptoms underwent upper endoscopy and antral gastric biopsy. Histologic gastritis was diagnosed and degree of activity graded on hematoxylin-eosin stain. H. pylori organisms were identified by acridine orange stain. A single pathologist evaluated the biopsy specimens. H. pylori was found in 15% (11 of 73) of AIDS patients. Histologic chronic active gastritis was evident in 94.5% (69 of 73) of the study group. H. pylori was identified in 15.9% (11 of 69) of biopsy specimens with histologic chronic active gastritis. The organism was more common in biopsy specimens with a higher grade of activity in the chronic gastritis. Endoscopic erosions or ulcers were noted in 11 patients (seven gastric, four duodenal). H. pylori was present in 18% (2 of 11) of AIDS patients with erosions or ulcers. The prevalence of H. pylori in AIDS patients with histologic chronic active gastritis is much lower than the prevalence previously reported for HIV-negative patients with similar pathology. The low prevalence observed does not implicate H. pylori as the causal agent in most chronic active gastritis in the AIDS population. Impaired acid secretion may reduce colonization of gastric mucosa and explain the low rate of H. pylori observed.     

A new endoscopic method of gastric acid secretory testing

OBJECTIVE: To date, the effect of Helicobacter pylori on acid secretion remains controversial. To evaluate changes in the gastric acid secretory response before and after H. pylori eradication in a large number of patients, we devised a new endoscopic method of gastric acid secretory testing, the endoscopic gastrin test (EGT). METHODS: In EGT, endoscopy was begun 15 min after intramuscular injection of 4 microg/kg tetragastrin. Gastric fluid secreted between 20 and 30 min after gastrin injection was aspirated and collected during endoscopic examination. The amount of acid in the sample collected over this 10-min period was estimated by titration and expressed in H+ mEq/10 min. Fifteen subjects underwent a conventional secretory test using a nasogastric tube (conventional method) and EGT on different days to assess the correlation between results obtained with the two methods. In 10 of these subjects, EGT was repeated under the same conditions to assess its reproducibility. RESULTS: EGT values correlated very well with peak acid output determined by the conventional method (n = 15, r = 0.92) and had high reproducibility (n = 10, CV = 5.6). We noted that EGT takes just a little longer to perform than a routine endoscopic examination, and the influence of an endoscope in the stomach on acid secretion was not present. CONCLUSION: The EGT should be very useful as a rapid, simple substitute for conventional secretory testing when repeated gastric secretory tests are required, especially in investigating the effect of H. pylori on acid secretion in a larger population.     

Influence of bacterial CagA status on gastritis, gastric function indices, and pattern of symptoms in H. pylori-positive dyspeptic patients

OBJECTIVE: To date, little is known about a possible relationship between H. pylori-related disturbances of gastric function and the bacterial virulence. The aim of this study was to assess whether certain gastric function indices as well as the pattern of symptoms in nonulcer dyspepsia (NUD) are related to CagA status. METHODS: A total of 56 consecutive patients with NUD (38 H. pylori-positive and 18 H. pylori-negative) were studied. Dyspeptic symptoms were categorized according to the predominant complaints and scored for severity and frequency. In all subjects, basal and pentagastrin-stimulated acid secretion, fasting and meal-induced gastrin release, fasting serum pepsinogen I (PG I) levels, and gastric emptying of solids were determined. CagA status was determined by assaying serum CagA IgG antibodies by western blotting. RESULTS: Eighteen of 38 (47%) H. pylori-positive dyspeptics were CagA seropositive. Type and severity of dyspeptic symptoms did not significantly differ between CagA-positive and CagA-negative dyspeptics nor between H. pylori-positive and negative patients. Among the gastric function indices studied, only meal-stimulated gastrin was significantly influenced by CagA status (peak gastrin 129.9 [44.1] vs 99.1 [48.6] pg/ml in CagA-positive and negative NUD, respectively), but this was not accompanied by any significant modification of basal or stimulated acid secretion or gastric emptying of solids. The activities of both antral and corpus gastritis in NUD harboring CagA-positive strains were significantly higher than those of CagA-negative NUD. Accordingly, serum PG I levels were significantly higher in CagA-positive than CagA-negative or H. pylori-negative dyspeptics. CONCLUSIONS: These findings support a role for CagA status in influencing the activity and perhaps the distribution of gastritis in NUD, as well as the degree of gastrin response to a meal; however, this is not accompanied by disturbances of acid secretion or gastric emptying or by differences in the type and severity of symptoms.     

Reflux esophagitis; is the preventive eradication of Helicobacter pylori needed in patients on omeprazole?

The pattern of Helicobacter pylori gastritis depends on acid secretion. Profound acid suppressive therapy with proton pump inhibitors leads to a decrease of antral gastritis, but an increased severity of corpus gastritis. As such, maintenance therapy with these drugs for gastroesophageal reflux disease has consistently been associated with an increased incidence of atrophic gastritis in H. pylori infected patients. For this reason, the preventive effect of H. pylori eradication in these patients needs to be considered; this is being studied in prospective trials.     

Does Helicobacter pylori-induced gastritis enhance food-stimulated insulin release?

The fact that H. pylori gastritis results in an increased secretion of basal and meal-stimulated gastrin, which is also a physiologic amplifier of insulin release directed us to investigate whether H. pylori gastritis may lead to an enhancement of nutrient-stimulated insulin secretion. For this purpose, we have investigated the insulin responses to both oral glucose and a mixed meal in 15 patients with H. pylori gastritis before and one month after the eradication therapy and also in 15 H. pylori-negative control subjects. The areas under the curve (AUC) for serum insulin following both oral glucose and a mixed meal in the patients with H. pylori gastritis before the eradication were significantly (P < 0.05) higher than those in the H. pylori-negative controls. After the eradication of H. pylori, the AUC for serum insulin following oral glucose and mixed meal decreased by 9.4% and 13.1%, respectively (P < 0.001 in both), and serum basal and meal-stimulated gastrin levels decreased significantly (P < 0.001). These results suggest that H. pylori gastritis enhances glucose and meal-stimulated insulin release probably by increasing gastrin secretion.     

Fibrinolytic components in nasal mucosa and nasal secretion

Effects of a newly synthesized antiulcer agent, YJA20379-4, on gastric proton pump (H+/K+-ATPase) activity, Helicobacter pylori (H. pylori) growth, gastric acid secretion, and gastro-duodenal lesions, were examined in comparison with those of omeprazole. YJA20379-4 markedly inhibited the H+/K+-ATPase activity in a concentration-dependent manner and the inhibitory effect was increased under a weak acidic condition; the IC50 values were 32 and 81 microM at pH 6.4 and 7.4, respectively. The inhibition was completely antagonized by 0.5 mM dithiothreitol (DTT). In addition, YJA20379-4 showed a significant anti-H. pylori activity determined by the agar dilution method. The value of minimum inhibitory concentration (MIC, 3.9-11.7 microg/ml) was at least 3 times more potent than that of omeprazole. In pylorus ligated rats, YJA20379-4 inhibited basal gastric acid secretion when administered by the intraduodenal route (ED50: 23.6 mg/kg). In experimental ulcer models, YJA20379-4 administered by the oral route dose-dependently prevented the development of gastro-duodenal lesions in rats. Moreover, repeated administration of YJA20379-4 promoted the healing of gastric ulcers induced by acetic acid. On the basis of the data obtained, it is suggested that YJA20379-4 has a wide spectrum of antiulcer activities, and its mode of antiulcer actions is dependent on the inhibition of H+/K+-ATPase activity and H. pylori growth and the enhancement of a mucosal defense. Thus, YJA20379-4 might prove to be a beneficial therapy for gastritis and peptic ulcer diseases.     

Skull base aspergillosis granuloma originating from the sphenoid sinus: a case report

To clarify the prevalence of Helicobacter pylori infection in enlarged fold gastritis, serum immunoglobulin (Ig) G antibody to H pylori was determined in 19 patients with severely enlarged gastric body folds (the widest fold greater than 10 mm on the radiograph), 55 patients with moderately enlarged folds (6 to 10 mm) and 44 control subjects (5 mm or less). The prevalence of serum IgG antibody to H pylori in the severe (100%) and moderate groups (100%) was significantly higher than that in controls (34.1%) (P < 0.01). There were significant differences among the three groups in serum gastrin, pepsinogen I and pepsinogen II levels (severe had the highest levels, followed by moderate and then controls, P < 0.001). H pylori colonization in the gastric mucosa was confirmed by culture, urease test or both, and inflammation by hematoxylin and eosin stain in the 25 H pylori seropositive patients who underwent endoscopy and biopsy. Results suggest that H pylori infection is highly prevalent in enlarged fold gastritis. Further studies on enlarged fold gastritis and H pylori infection are needed.     

Helicobacter pylori in 1997

In this review Helicobacter pylori (H. pylori) infection and its relation to different diseases is presented. H. pylori doesn't cause inconvenience to most infected people, though all infected persons have chronic active gastritis. The 10 year risk of peptic ulcer for people infected with H. pylori is about 10%. Randomized double-blinded trials have shown that eradication of H. pylori can cure most patients with peptic ulcer disease. Some people infected with H. pylori develop atrophic gastritis which is a risk factor for development of gastric cancer. It is not known if H. pylori screening and eradication would have a prophylactic effect against gastric cancer. It is also unknown if persons with non-organic dyspepsia and persons in long-term treatment with proton-pump-inhibitors would benefit from H. pylori eradication.     

Developing a critical pathway for orientation

In an attempt to establish the etiologic role of Helicobacter pylori (H. pylori) in gastric and/or duodenal pathology, 169 patients were tested and compared with a control group of 25 healthy subjects, for a total of 194 subjects. Data on sex, age, familiarity, smoking, coffee and alcohol habits were collected and each patient underwent histological, microbiological and immunological tests. 80 (41.2%) subjects were found positive to H. pylori. This bacterium was detected in 53.3% of patients with gastric ulcer while IgG were found in 86.7%; in 50% of patients with chronic atrophic gastritis while IgG were detected in 80%; in 48.5% of patients with duodenal ulcer while IgG were found in 87.9%; in 41.8% of patients with superficial chronic gastritis while IgG were detected in 80.2%. In the control group of healthy patients H. pylori was found in 28% of patients while IgG were detected in 62.5%. The results do not confirm a direct clear-cut correlation between this microorganism and the pathologies studied.