Antigastric autoantibodies in Helicobacter pylori infection: role in gastric mucosal inflammation

Helicobacter pylori seropositivity is associated with antinuclear antibodies in US adults, NHANES 1999-2000

Infectious diseases, such as Helicobacter pylori, which produce systemic inflammation may be one key factor in the onset of autoimmunity. The association between H. pylori and antinuclear antibodies (ANA), a marker of autoimmunity, has been understudied. Data from the 1999–2000 National Health and Nutrition Examination Survey were used to evaluate the cross-sectional association between H. pylori seroprevalence and ANA positivity in US adults aged ≥20 years. ANA was measured in a 1:80 dilution of sera by indirect immunofluorescence using HEp-2 cells (positive ⩾3). H. pylori immunoglobulin G enzyme-linked immunosorbent assays were used to categorise individuals as seropositive or seronegative. H. pylori seropositivity and ANA positivity were common in the adult US population, with estimated prevalences of 33.3% and 9.9%, respectively. Both were associated with increasing age. H. pylori seropositivity was associated with higher odds of ANA (prevalence odds ratio = 1.89, 95% confidence interval = 1.08–3.33), adjusted for age, sex, race/ethnicity, educational attainment and body mass index. H. pylori infection may be one key factor in the loss of self-tolerance, contributing to immune dysfunction.

Gastric parietal cell antibodies, Helicobacter pylori infection, and chronic atrophic gastritis: evidence from a large population-based study in Germany

BACKGROUND

Striking similarities between autoimmune gastritis and Helicobacter Pylori (H. pylori)-associated gastritis have suggested a potential link between these two pathologic conditions in the progression of chronic atrophic gastritis (CAG); however, evidence has remained conflicting.

METHODS

Serum pepsinogen I and II, and antibodies against H. pylori in general, the cytotoxin-associated gene A protein (CagA) and parietal cells were measured by ELISA in 9,684 subjects aged 50 to 74 years. Antigastric parietal cell antibody (APCA) prevalence was examined in the overall population and according to sex, age, and H. pylori serostatus. The association between APCA prevalence and CAG was assessed by logistic regression, overall and according to H. pylori status, controlling for potential confounding factors.

RESULTS

Overall APCA prevalence was 19.5%. APCA prevalence was strongly associated with CAG, and the association was increasing with increasing severity of CAG. Furthermore, the association between APCA and CAG was even stronger among H. pylori-negative subjects [odds ratio (OR) = 11.3; 95% confidence interval (CI): 7.5-17.1)] than among H. pylori-positive subjects (OR = 2.6; 95% CI: 2.1-3.3).

CONCLUSIONS

APCA may play a role on the development of gastric atrophy, irrespective of H. pylori infection.

IMPACT

Assessment of APCA might be a useful complement to established markers (such as pepsinogens and H. pylori antibodies) in screening for CAG.

Alzheimer's disease and Helicobacter pylori infection: Defective immune regulation and apoptosis as proposed common links

Although degenerative diseases of the central nervous system, including Alzheimer's disease (AD), have an increasingly high impact on aged population their association with Helicobacter pylori (H. pylori) infection has not as yet been thoroughly researched. Current H. pylori infection appears to induce irregular humoral and cellular immune responses that, owing to the sharing of homologous epitopes (molecular mimicry), cross-react with components of nerves, thereby contributing and possibly perpetuating the apoptotic neural tissue damage observed in neurodegenerative diseases including AD. An association between AD and H. pylori infection has been recently addressed by two studies. A higher seropositivity for anti-H. pylori immunoglobulin G antibodies in 30 patients with AD than in 30 age-matched controls was reported in one study; this serological test, however, has limitations because it does not discriminate between current and old infections. In the other study, by introducing the histological method (the actual gold standard) for diagnosis of H. pylori infection, we reported a higher prevalence of H. pylori infection in 50 AD patients than in 30 anemic controls. This pathogen may influence the pathophysiology of AD by promoting platelet and platelet-leukocyte aggregation; releasing various pro-inflammatory and vasoactive substances; developing cross-mimicry with host antigens; producing reactive oxygen metabolites and circulating lipid peroxides; influencing the apoptotic process; and increasing, through induction of atrophic gastritis, homocysteine, which contributes to vascular disorders implicated in endothelial damage and neurodegeneration.

Association between Helicobacter pylori infection and acute inflammatory demyelinating polyradiculoneuropathy

The aim of this study was to investigate a possible association between Helicobacter pylori infection and acute inflammatory demyelinating polyradiculoneuropathy (AIDP). Of 17 consecutive patients with Guillain-Barre syndrome (GBS), 13 patients (six females; mean age 50 +/- 24 years) with AIDP were investigated. Clinical status was evaluated according to Hughes' score, and electrophysiological tests were performed within 2 weeks from disease onset. Helicobacter pylori infection was detected histologically and serum H. pylori-specific IgG antibodies were analysed by ELISA. Twenty asymptomatic patients (12 females; mean age 63 +/- 8 years), undergoing upper gastrointestinal endoscopy for investigation of mild iron deficiency anaemia, served as controls. Helicobacter pylori was found in 12 of 13 AIDP patients (92%), and in 10 of 20 controls (50%), (P = 0.02). Electrophysiological studies showed demyelination in all AIDP patients. High levels of anti-H. pylori IgG antibodies correlated with advanced clinical status. Five of seven AIDP patients with high levels of anti-H. pylori IgG antibodies had delayed F-wave latencies, indicating affection of proximal segments of peripheral nerves. Helicobacter pylori infection seems to be more frequent in AIDP patients. Anti-H. pylori titre might reflect advanced clinical status. Anti-H. pylori IgG antibodies are also associated with involvement of the proximal parts of peripheral nerves in AIDP.

Histologic changes after H.pylori eradication with Killing Hp decoction for chronic gastritis

AIM

To study the histologic changes after H.pylori eradication with Killing Hp decoction for chronic gastritis.

METHODS

Total 81 cases of chronic gastritis with H.pylori infection were prospectively studied. After a 7-day triple therapy (bismuth potassium citrate, clarithromycin and tinidazole), the patients were divided randomly into 3 groups. Group A (n = 23): Killing Hp decoction, 1 Bid; GroupB (n = 15): marzulene-s-granules, 1 Tid; Group C (n = 15): aluminium hydroxide compound, 3-5 Bid; An endoscopy was performed at the frist and third months. Histological changes of gastric mucosa were compared before and after the treatment according to Sydney classification. COX-2(cyclooxygenase-2) protein was detected by immunohistochemical method, and the computer image processing system was used. For the patients of no eradication after one course therapy, anti-H.pylori treatment continued.

RESULTS

H.pylori eradication got a very good curative effect in 81.9% of the patients. A favourable histologic change of acute inflammatory infiltration was found (average values from 0.79±0.78 to 0.042±0.14) (P<0.001).The mean percentage of COX-2 positive cells significantly decreased after H.pylori eradication [(43.5±12.3)%, (32.3±8.3)%, P<0.001]. No chronic inflammation was observed after one month therapy (1.90±0.68, 1.67±0.76, P>0.05. Compared to the controls, after Killing Hp decoction treatment for three months, the score corresponding to chronic gastritis declined progressively (average values from 2.9±0.6 to 1.30±0.60, P<0.001), and the mean percentage of COX-2 positive cells staining got further decreased and reached a statistically significant difference, compared with the results obtained at the first month. [(31.6±5.9)%, (27.09±5.16)%, P<0.05]. Gastric atrophic lesions were improved after "killing Hp decoction" for three-month treatment.

CONCLUSION

H. pylori related gastritis should be treated further with Killing Hp decoction after H.pylori eradication.

Impact of Helicobacter pylori on the development of vitamin B12 deficiency in the absence of gastric atrophy

BACKGROUND

Cobalamin (vitamin B12) deficiency is associated with Helicobacter pylori infection. This study examined how serum vitamin B12 levels relate to gastric mucosa H. pylori density and histology, and to hematological findings in patients with minimal or no gastric atrophy. A second aim was to confirm that H. pylori eradication therapy increases serum B12.

MATERIALS AND METHODS

Biopsies of the gastric mucosa from a population of dyspeptic patients were graded for level of chronic inflammation, neutrophil activity, atrophy, and H. pylori density. A total of 145 H. pylori-infected patients with minimal or no atrophy were included in the study. Serum cobalamin level, hemoglobin level, and mean corpuscular volume were measured in the 145 patients before eradication therapy, and in 65 of the subjects after treatment. The hematologic findings before and after eradication therapy and correlations between serum vitamin B12 level and histologic parameters, hematologic findings, and patient age were statistically analyzed.

RESULTS

There was no significant correlation between serum cobalamin level and patient age. Before treatment all the histopathological scores were inversely correlated with serum vitamin B12 level (p <.01) on univariate analysis. Only H. pylori density was significantly associated with B12 level on multivariate analysis. Serum hemoglobin and cobalamin levels were significantly increased after treatment, regardless of H. pylori eradication status (p <.001).

CONCLUSION

The findings provide strong evidence that H. pylori infection is associated with cobalamin deficiency, and show that this is true even in patients with non-ulcer dyspepsia and minimal or no gastric atrophy.

Alteration of histological gastritis after cure of Helicobacter pylori infection

BACKGROUND

It is still disputed whether gastric atrophy or intestinal metaplasia improves after the cure of Helicobacter pylori infection.

AIM

To clarify the histological changes after the cure of H. pylori infection through a literature survey.

METHODS

Fifty-one selected reports from 1066 relevant articles were reviewed. The extracted data were pooled according to histological parameters of gastritis based on the (updated) Sydney system.

RESULTS

Activity improved more rapidly than inflammation. Eleven of 25 reports described significant improvement of atrophy. Atrophy was not improved in one of four studies with a large sample size (> 100 samples) and in two of five studies with a long follow-up period (> 12 months), suggesting that disagreement between the studies was not totally due to sample size or follow-up period. Methodological flaws, such as patient selection, and statistical analysis based on the assumption that atrophy improves continuously and generally in all patients might be responsible for the inconsistent results. Four of 28 studies described significant improvement of intestinal metaplasia [corrected].

CONCLUSIONS

Activity and inflammation were improved after the cure of H. pylori infection. Atrophy did not improve generally among all patients, but improved in certain patients. Improvement of intestinal metaplasia was difficult to analyse due to methodological problems including statistical power.