Helicobacter pylori gastritis and serum pepsinogen levels in a healthy population: development of a biomarker strategy for gastric atrophy in high risk groups

Serum Helicobacter pylori antibody reactivity in seven Asian countries using an automated latex aggregation turbidity assay

BACKGROUND AND AIM

To determine the application range of diagnostic kits utilizing anti-Helicobacter pylori antibody, we tested a newly developed latex aggregation turbidity assay (latex) and a conventional enzyme-linked immunosorbent assay (E-plate), both containing Japanese H. pylori protein lysates as antigens, using sera from seven Asian countries.

METHODS

Serum samples (1797) were obtained, and standard H. pylori infection status and atrophy status were determined by culture and histology (immunohistochemistry) using gastric biopsy samples from the same individuals. The two tests (enzyme-linked immunosorbent assay and latex) were applied, and receiver operating characteristics analysis was performed.

RESULTS

Area under the curve (AUC) from the receiver operating characteristic of E-plate and latex curves were almost the same and the highest in Vietnam. The latex AUC was slightly lower than the E-plate AUC in other countries, and the difference became statistically significant in Myanmar and then Bangladesh as the lowest. To consider past infection cases, atrophy was additionally evaluated. Most of the AUCs decreased using this atrophy-evaluated status; however, the difference between the two kits was not significant in each country, but the latex AUC was better using all samples. Practical cut-off values were 3.0 U/mL in the E-test and 3.5 U/mL in the latex test, to avoid missing gastric cancer patients to the greatest extent possible.

CONCLUSIONS

The kits were applicable in all countries, but new kits using regional H. pylori strains are recommended for Myanmar and Bangladesh. Use of a cut-off value lower than the best cut-off value is essential for screening gastric cancer patients.

Fundic gland polyps accurately predict a low risk of future gastric carcinogenesis

OBJECTIVES

Few reports have analyzed the clinical importance of sporadic fundic gland polyps (FGPs). The aim of this study was to investigate the relationship between sporadic FGPs and condition of the gastric mucosa stratified by serum pepsinogen levels and Helicobacter pylori antibody level.

METHODS

Three hundred and seventy-five subjects undergoing gastrointestinal endoscopy were enrolled. Subjects on proton pump inhibitors were excluded. Pathologically proven FGPs, and other endoscopic findings (reflux esophagitis, gastric and duodenal ulcer) were examined and serum pepsinogen levels, H. pylori antibody concentration and gastric juice pH were measured simultaneously. Subjects with normal serum pepsinogen and negative H. pylori antibodies were defined as having "low risk" stomachs, suggesting low risk of gastric carcinogenesis.

RESULTS

Of the 375 subjects, 44 showed FGPs. The prevalence of "low risk" stomach in subjects with and without FGPs was 98% and 48%, respectively. Multivariable logistic regression analysis indicated three variables as independent factors positively associated with "low risk" stomachs: FGPs (odds ratio [OR] 38.6), reflux esophagitis (OR 4.8), and age<60 years (OR 1.89). Gastric juice pH, which is associated with mucosal atrophy grade and low pH indicates less mucosal atrophy, was significantly lower in subjects with (1.64 ± 0.64) than without FGPs in "low risk" (1.94 ± 1.12) and "high risk" stomachs (3.99 ± 2.31).

CONCLUSIONS

Sporadic FGPs tend to be related to the least atrophic mucosa among non-gastric atrophy subjects without H. pylori infection, and can be used as predictors of a low risk of gastric carcinogenesis.

Pepsinogen II can be a potential surrogate marker of morphological changes in corpus before and after H. pylori eradication

Background. The aim of this investigation is to study the relationship between gastric morphology and serum biomarkers before and after Helicobacter pylori eradication. Methods. First-degree relatives of gastric cancer patients underwent gastroscopy before and 2.5 years after H. pylori eradication. The morphological changes in two categories (normal to mild and moderate to severe) were compared with level of pepsinogens I and II before eradication (n = 369), after eradication (n = 115), and in those with persistent infection (n = 250). Results: After eradication, pepsinogen I decreased to 70% and pepsinogen II to 45% of the previous values. Unlike pepsinogen II and pepsinogen I to II ratio that were affected by the severity of inflammation and atrophy in corpus in all groups, pepsinogen I generally did not change. After eradication, subjects with high mononuclear infiltration in corpus had lower pepsinogen I (54 versus 77.1 μ/mL), higher pepsinogen II (9.4 versus 6.9 μ/mL), and lower ratio (7.9 versus 11.6) than those without (P < 0.05). Conclusion. Pepsinogen II is a good marker of corpus morphological changes before and after H. pylori eradication.

The association between precancerous gastric lesions and serum pepsinogens, serum gastrin, vascular endothelial growth factor, serum interleukin-1 Beta, serum toll-like receptor-4 levels and Helicobacter pylori Cag A status

BACKGROUND AND OBJECTIVE

The aim of this study was to investigate the association between serum pepsinogens, serum gastrin, serum vascular endothelial growth factor, serum interleukin-1 Beta, serum toll-like receptor-4 levels and Helicobacter pylori Cag A status in patients with various gastric precancerous lesions.

METHODS

One hundred and sixty two consecutive patients with various gastric lesions [38 (23.5%) H. pylori positive chronic non-atrophic gastritis, 45 (27.8%) autoimmune gastritis, 42 intestinal metaplasia and 37 dysplasia] were enrolled into the study. Serum pepsinogen I and II, gastrin 17, vascular endothelial growth factor, interleukin-1 Beta, toll-like receptor-4 levels, H. pylori Cag A status were evaluated.

RESULTS

H. pylori was positive in 98 (60.5%) patients and 38 of these patients were Cag A positive. Serum pepsinogen level was significantly lower in patients with autoimmune atrophic gastritis compared to the patients with non-atrophic chronic gastritis (p<0.001), intestinal metaplasia (P<0.001) and dysplasia (P=0.002). Mean serum gastrin was 1209.6±268.48 pg/mL in patients with autoimmune atrophic gastritis and 234.95±184.018 pg/mL in patients with chronic non-atrophic gastritis. Mean toll-like receptor-4 level was 0.56±0.098 ng/mL in patient with dysplasia, and this value was higher compared to patients with chronic non-atrophic gastritis (P=0.007), autoimmune atrophic gastritis (P=0.003) and intestinal metaplasia (P=0.006). Interleukin-1 Beta level was significantly lower in patients with dysplasia compared to patients with chronic non-atrophic gastritis (P=0.034).

CONCLUSIONS

Serum pepsinogens, serum gastrin and H. pylori Cag A status are important tests in detecting gastric precancerous lesions. However, toll-like receptor-4 may be a sensitive test to differentiate the patients with dysplasia from the other precancerous gastric lesions. Non-invasive tests are sensitive in the diagnosis of gastric precancerous lesions.

Rationale in diagnosis and screening of atrophic gastritis with stomach-specific plasma biomarkers

BACKGROUND AND AIMS

Atrophic gastritis (AG) results most often from Helicobacter pylori (H. pylori) infection. AG is the most important single risk condition for gastric cancer that often leads to an acid-free or hypochlorhydric stomach. In the present paper, we suggest a rationale for noninvasive screening of AG with stomach-specific biomarkers.

METHODS

The paper summarizes a set of data on application of the biomarkers and describes how the test results could be interpreted in practice.

RESULTS

In AG of the gastric corpus and fundus, the plasma levels of pepsinogen I and/or the pepsinogen I/pepsinogen II ratio are always low. The fasting level of gastrin-17 is high in AG limited to the corpus and fundus, but low or non-elevated if the AG occurs in both antrum and corpus. A low fasting level of G-17 is a sign of antral AG or indicates high intragastric acidity. Differentiation between antral AG and high intragastric acidity can be done by assaying the plasma G-17 before and after protein stimulation, or before and after administration of the proton pump inhibitors (PPI). Amidated G-17 will rise if the antral mucosa is normal in structure. H. pylori antibodies are a reliable indicator of helicobacter infection, even in patients with AG and hypochlorhydria.

CONCLUSIONS

Stomach-specific biomarkers provide information about the stomach health and about the function of stomach mucosa and are a noninvasive tool for diagnosis and screening of AG and acid-free stomach.

Management of precancerous conditions and lesions in the stomach (MAPS): guideline from the European Society of Gastrointestinal Endoscopy (ESGE), European Helicobacter Study Group (EHSG), European Society of Pathology (ESP), and the Sociedade Portuguesa de Endoscopia Digestiva (SPED)

Atrophic gastritis, intestinal metaplasia, and epithelial dysplasia of the stomach are common and are associated with an increased risk for gastric cancer. In the absence of guidelines, there is wide disparity in the management of patients with these premalignant conditions. The European Society of Gastrointestinal Endoscopy (ESGE), the European Helicobacter Study Group (EHSG), the European Society of Pathology (ESP) and the Sociedade Portuguesa de Endoscopia Digestiva (SPED) have therefore combined efforts to develop evidence-based guidelines on the management of patients with precancerous conditions and lesions of the stomach (termed MAPS). A multidisciplinary group of 63 experts from 24 countries developed these recommendations by means of repeat online voting and a meeting in June 2011 in Porto, Portugal. The recommendations emphasize the increased cancer risk in patients with gastric atrophy and metaplasia, and the need for adequate staging in the case of high grade dysplasia, and they focus on treatment and surveillance indications and methods.

Accuracy and cut-off values of pepsinogens I, II and gastrin 17 for diagnosis of gastric fundic atrophy: influence of gastritis

Background

To establish optimal cutoff values for serologic diagnosis of fundic atrophy in a high-risk area for oesophageal squamous cell carcinoma and gastric cancer with high prevalence of Helicobacter pylori (H. pylori) in Northern Iran, we performed an endoscopy-room-based validation study.

Methods

We measured serum pepsinogens I (PGI) and II (PGII), gastrin 17 (G-17), and antibodies against whole H. pylori, or cytotoxin-associated gene A (CagA) antigen among 309 consecutive patients in two major endoscopy clinics in northeastern Iran. Updated Sydney System was used as histology gold standard. Areas under curves (AUCs), optimal cutoff and predictive values were calculated for serum biomarkers against the histology.

Results

309 persons were recruited (mean age: 63.5 years old, 59.5% female). 84.5% were H. pylori positive and 77.5% were CagA positive. 21 fundic atrophy and 101 nonatrophic pangastritis were diagnosed. The best cutoff values in fundic atrophy assessment were calculated at PGI<56 µg/l (sensitivity: 61.9%, specificity: 94.8%) and PGI/PGII ratio<5 (sensitivity: 75.0%, specificity: 91.0%). A serum G-17<2.6 pmol/l or G-17>40 pmol/l was 81% sensitive and 73.3% specific for diagnosing fundic atrophy. At cutoff concentration of 11.8 µg/l, PGII showed 84.2% sensitivity and 45.4% specificity to distinguish nonatrophic pangastritis. Exclusion of nonatrophic pangastritis enhanced diagnostic ability of PGI/PGII ratio (from AUC = 0.66 to 0.90) but did not affect AUC of PGI. After restricting study samples to those with PGII<11.8, the sensitivity of using PGI<56 to define fundic atrophy increased to 83.3% (95%CI 51.6–97.9) and its specificity decreased to 88.8% (95%CI 80.8–94.3).

Conclusions

Among endoscopy clinic patients, PGII is a sensitive marker for extension of nonatrophic gastritis toward the corpus. PGI is a stable biomarker in assessment of fundic atrophy and has similar accuracy to PGI/PGII ratio among populations with prevalent nonatrophic pangastritis.

Multifaceted Assessment of Chronic Gastritis: A Study of Correlations between Serological, Endoscopic, and Histological Diagnostics

Aim. Chronic gastritis was assessed serologically, endoscopically and histologically to identify correlations between these methods. Methods. Subjects comprised 319 patients who had provided informed consent. Serological assessment of chronic gastritis was based on the pepsinogen test method. Endoscopic gastritis and histological gastritis were assessed and scored according to the Kimura-Takemoto classification system and the updated Sydney classification system respectively, and correlations between these three methods were studied. Results. Pepsinogen I/II ratio showed a significant correlation to the extent of mononuclear cell infiltration of the gastric corpus. When histological gastritis was divided, on the basis of the distribution of mononuclear cell infiltration, into gastritis limited to the antrum and corpus gastritis, these types were distinguished with high accuracy using a pepsinogen I/II ratio of 3 as the cutoff. A good correlation was also seen between pepsinogen I/II ratio and development of atrophy in endoscopic gastritis, where groups with and without advanced atrophy were also distinguished with high accuracy using a cutoff value of 3. Conclusion. Significant correlations exist between serum pepsinogen levels, endoscopic gastritis, and histological gastritis. Pepsinogen I/II ratio allows prediction of the existence of endoscopic gastritis and histological gastritis, or the extent of their development, with high accuracy.

Multifaceted Assessment of Chronic Gastritis: A Study of Correlations between Serological, Endoscopic, and Histological Diagnostics

Aim. Chronic gastritis was assessed serologically, endoscopically and histologically to identify correlations between these methods. Methods. Subjects comprised 319 patients who had provided informed consent. Serological assessment of chronic gastritis was based on the pepsinogen test method. Endoscopic gastritis and histological gastritis were assessed and scored according to the Kimura-Takemoto classification system and the updated Sydney classification system respectively, and correlations between these three methods were studied. Results. Pepsinogen I/II ratio showed a significant correlation to the extent of mononuclear cell infiltration of the gastric corpus. When histological gastritis was divided, on the basis of the distribution of mononuclear cell infiltration, into gastritis limited to the antrum and corpus gastritis, these types were distinguished with high accuracy using a pepsinogen I/II ratio of 3 as the cutoff. A good correlation was also seen between pepsinogen I/II ratio and development of atrophy in endoscopic gastritis, where groups with and without advanced atrophy were also distinguished with high accuracy using a cutoff value of 3. Conclusion. Significant correlations exist between serum pepsinogen levels, endoscopic gastritis, and histological gastritis. Pepsinogen I/II ratio allows prediction of the existence of endoscopic gastritis and histological gastritis, or the extent of their development, with high accuracy.

Correlation of serum pepsinogens and gastrin-17 with atrophic gastritis in gastroesophageal reflux patients: a matched-pairs study

BACKGROUND AND AIM

An algorithm (GastroPanel) for the non-invasive diagnosis of atrophic gastritis has been previously proposed, based on serum pepsinogen-I, gastrin-17, and Helicobacter pylori (H. pylori) antibodies. The aim of the present study was to evaluate whether serum markers correlate with and predict gastric atrophy in gastroesophageal reflux disease (GERD) patients.

METHODS

The baseline data of the prospective ProGERD study, a study on the long-term course of GERD (n=6215 patients), served to select patients with atrophic gastritis diagnosed in biopsies from gastric antrum and corpus, and control cases without atrophy. A total of 208 pairs were matched for age, sex, GERD status (erosive vs non-erosive), presence of Barrett's esophagus, and histological H. pylori status were retrieved. Serum pepsinogen-I, gastrin-17, and H. pylori antibodies were determined using specific enzyme immunoassays.

RESULTS

A significant negative correlation was found between the degree of corpus atrophy and the level of serum pepsinogen-I. A previously-reported negative correlation between the degree of antral atrophy and serum gastrin-17 could not be confirmed. The low sensitivity (0.32) and specificity (0.70) of the GastroPanel algorithm were mainly due to over diagnosis and under diagnosis of advanced atrophy in the antrum.

CONCLUSION

The diagnostic validity of the GastroPanel algorithm to diagnose gastric atrophy non-invasively is not sufficient for general use in GERD patients.

The validity of a biomarker method for indirect detection of gastric mucosal atrophy versus standard histopathology

BACKGROUND

Atrophy of the stomach mucosa is considered to be premalignant lesion for gastric cancer development; easy identification of this condition from a blood-sample would allow identifying the group of individuals at increased risk for cancer development.

AIMS

The objective of the current study was to validate a biomarker method (pepsinogen I/II ratio and gastrin-17) for indirect detection of atrophy of the stomach mucosa versus standard histopathology in Caucasian and Asian populations.

METHODS

Altogether, 241 patients aged 55 and above referred for upper endoscopy due to dyspeptic symptoms (125 from Latvia, 76 from Lithuania, and 40 from Taiwan) were enrolled. Pepsinogen I, pepsinogen II, gastrin-17 (the latter after stimulation with protein-rich meal) and IgG/IgA antibodies to Helicobacter pylori infection were determined by ELISA method; standard histopathology according to the updated Sydney classification read by two independent expert pathologists was used for the comparison.

RESULTS

Pepsinogen I/II ratio below 3 was well related to atrophy (moderate to severe) in the corpus part of the stomach (P < 0.0001) with 83.3% sensitivity and 87.1% specificity. Gastrin-17 below 5 pmol/L was related to atrophy in the antral part (P = 0.007) with 36.8% sensitivity and 86.5% specificity.

CONCLUSIONS

Decreased pepsinogen I/II ratio is a reliable marker for atrophy in the corpus, and may be recommended for identification of individuals with this type of atrophy. The utility of gastrin-17 for the detection of atrophy in the antral part of the stomach still requires further evaluation due to the low sensitivity.

Serum biomarkers provide an accurate method for diagnosis of atrophic gastritis in a general population: The Kalixanda study

OBJECTIVE

Serological biomarkers can be used for non-invasive diagnosis of gastritis and atrophic gastritis. The aim of this study was to compare the validity of serum levels of pepsinogen I (PGI) and II (PGII), gastrin-17 (G-17) and Helicobacter pylori antibodies (Hpab) with that of the gold standard histology for diagnosis of atrophic gastritis in a population sample from Northern Sweden.

MATERIAL AND METHODS

In all, 1000 subjects underwent endoscopies with biopsies. Serum biomarkers were available in 976 subjects for independent diagnosis of gastric mucosal status using a predetermined diagnostic algorithm.

RESULTS

Overall agreement between histology and serological biomarkers in diagnosing corpus atrophy was 96% (CI 95%: 95-97%). Sensitivity and specificity of markers for atrophic gastritis were 71% (CI 68-74%) and 98% (CI 97-99%) respectively, corresponding to 69% (CI 95%: 66-72%) and 98% (95% CI 97-99%) positive and negative predictive values. The positive likelihood ratio was 35.5 (95% CI: 35.0-36.0%). In subgroups with normal stomachs, H. pylori non-atrophic gastritis and H. pylori-negative gastritis by histology, the prevalence of corpus atrophy diagnosed with the biomarkers was 0.8% and 4.9%, respectively. In total, 6.6% of subjects in the study population had corpus atrophy according to the serological biomarkers. CONCLUSIONS. Serological biomarkers show a high degree of accuracy as a non-invasive method to diagnose corpus atrophy, which is common in the general population.

Serum biomarker tests are useful in delineating between patients with gastric atrophy and normal, healthy stomach

AIM

To study the value of serum biomarker tests to differentiate between patients with healthy or diseased stomach mucosa: i.e. those with Helicobacter pylori (H pylori) gastritis or atrophic gastritis, who have a high risk of gastric cancer or peptic ulcer diseases.

METHODS

Among 162 Japanese outpatients, pepsinogen I (Pg I) and II (Pg II) were measured using a conventional Japanese technique, and the European GastroPanel examination (Pg I and Pg II, gastrin-17 and H pylori antibodies). Gastroscopy with gastric biopsies was performed to classify the patients into those with healthy stomach mucosa, H pylori non-atrophic gastritis or atrophic gastritis.

RESULTS

Pg I and Pg II assays with the GastroPanel and the Japanese method showed a highly significant correlation. For methodological reasons, however, serum Pg I, but not Pg II, was twice as high with the GastroPanel test as with the Japanese test. The biomarker assays revealed that 5% of subjects had advanced atrophic corpus gastritis which was also verified by endoscopic biopsies. GastroPanel examination revealed an additional seven patients who had either advanced atrophic gastritis limited to the antrum or antrum-predominant H pylori gastritis. When compared to the endoscopic biopsy findings, the GastroPanel examination classified the patients into groups with "healthy" or "diseased" stomach mucosa with 94% accuracy, 95% sensitivity and 93% specificity.

CONCLUSION

Serum biomarker tests can be used to differentiate between subjects with healthy and diseased gastric mucosa with high accuracy.

Serum pepsinogen I, pepsinogen II, and gastrin 17 in relatives of gastric cancer patients: comparative study with type and severity of gastritis

BACKGROUND & AIMS

First-degree relatives of gastric cancer patients are at risk for developing precancerous conditions. The aim of this study was to investigate the potential of biomarkers pepsinogen I (PGI), pepsinogen II (PGII), their ratio (PG I:II), as well as gastrin 17 for screening of precancerous conditions and corpus predominant gastritis.

METHODS

First-degree relatives of gastric cancer patients underwent endoscopy. Three biopsy specimens from the antrum and 3 from the corpus were evaluated according to the Sydney classification. Serum was taken for the measurement of fasting PGI, PGII, and gastrin 17 by enzyme-linked immunosorbent assay kits.

RESULTS

A total of 481 patients were examined (age, 47.8 +/- 6.7 y). With the extension of gastritis, PGII was increased up to 2.5 times (6.6 +/- 2.8 microg/mL in normal mucosa, 9.5 +/- 6.7 microg/mL in antral gastritis, and 16.9 +/- 12.4 microg/mL in corpus-predominant gastritis; P < .01), PGI increased slightly (88.3 +/- 29.4 microg/mL in normal mucosa and 111.2 +/- 71.4 microg/mL in corpus-predominant gastritis), and gastrin 17 was increased substantially in corpus-predominant gastritis (15.3 +/- 19.5 pmol/mL vs 3.8 +/- 5.7 pmol/mL in normal mucosa). By using a cut-off value of 7.5 microg/mL for PGII, any type of gastritis from normal mucosa can be diagnosed with a sensitivity and specificity of 80%. The sensitivity and specificity of the PG I:II ratio (< or =3) and gastrin 17 (>17 pmol/mL) together were 9.4% and 99% for screening corpus-predominant gastritis and 14.8% and 97.8%, respectively, for screening intestinal metaplasia in the corpus.

CONCLUSIONS

PGII is a suitable marker for screening any gastritis from normal mucosa, but neither PGI, the PG I:II ratio, gastrin 17, nor their combination were able to select those with precancerous conditions and corpus-predominant gastritis among the first-degree relatives of gastric cancer patients.

Two distinct aetiologies of cardia cancer; evidence from premorbid serological markers of gastric atrophy and Helicobacter pylori status

BACKGROUND

Non-cardia gastric adenocarcinoma is positively associated with Helicobacter pylori infection and atrophic gastritis. The role of H pylori infection and atrophic gastritis in cardia cancer is unclear.

AIM

To compare cardia versus non-cardia cancer with respect to the premorbid state of the stomach.

METHODS

Nested case-control study. To each of 129 non-cardia and 44 cardia cancers, three controls were matched. Serum collected a median of 11.9 years before the diagnosis of cancer was tested for anti-H pylori antibodies, pepsinogen I:II and gastrin.

RESULTS

Non-cardia cancer was positively associated with H pylori (OR 4.75, 95% CI 2.56 to 8.81) and gastric atrophy (pepsinogen I:II <2.5; OR 4.47, 95% CI 2.71 to 7.37). The diffuse and intestinal histological subtypes of non-cardia cancer were of similar proportions and both showed a positive association with H pylori and atrophy. Cardia cancer was negatively associated with H pylori (OR 0.27, 95% CI 0.12 to 0.59), but H pylori-positive cardia cancer showed an association with gastric atrophy (OR 3.33, 95% CI 1.06 to 10.5). The predominant histological subtype of cardia cancer was intestinal and was not associated with gastric atrophy compared with the diffuse subtype ((OR 0.72, 95% CI 0.19 to 2.79) vs (OR 3.46, 95% CI 0.32 to 37.5)). Cardia cancer in patients with atrophy had an intestinal: diffuse ratio (1:1) similar to non-cardia cancer (1.9:1), whereas cardia cancers in patients without atrophy were predominantly intestinal (7:1).

CONCLUSION

These findings indicate two aetiologies of cardia cancer, one associated with H pylori atrophic gastritis, resembling non-cardia cancer, and the other associated with non-atrophic gastric mucosa, resembling oesophageal adenocarcinoma. Serological markers of gastric atrophy may provide the key to determining gastric versus oesophageal origin of cardia cancer.

CagA+ Helicobacter pylori infection and gastric cancer risk in the EPIC-EURGAST study

Helicobacter pylori (H. pylori), atrophic gastritis, dietary and life-style factors have been associated with gastric cancer (GC). These factors have been evaluated in a large case-control study nested in the European Prospective Investigation into Cancer and Nutrition carried out in 9 countries, including the Mediterranean area. Participants, enrolled in 1992-1998, provided life-style and dietary information and a blood sample (360,000; mean follow-up: 6.1 years). For 233 GC cases diagnosed after enrolment and their 910 controls individually-matched by center, gender, age and blood donation date H. pylori antibodies (antilysate and antiCagA) and plasma Pepsinogen A (PGA) were measured by ELISA methods. Severe chronic atrophic gastritis (SCAG) was defined as PGA circulating levels <22 microg/l. Overall, in a conditional logistic regression analysis adjusted for education, smoke, weight and consumption of total vegetables, fruit, red and preserved meat, H. pylori seropositivity was associated with GC risk. Subjects showing only antibodies anti-H. pylori lysate, however, were not at increased risk, while those with antiCagA antibodies had a 3.4-fold increased risk. Overall, the odds ratio associated with SCAG was 3.3 (95% CI 2.2-5.2). According to site, the risk of noncardia GC associated with CagA seropositivity showed a further increase (OR 6.5; 95% CI 3.3-12.6); on the other hand, a ten-fold increased risk of cardia GC was associated with SCAG (OR 11.0; 95% CI 3.0-40.9). These results support the causal relationship between H. pylori CagA+ strains infection, and GC in these European populations even after taking into account dietary habits. This association was limited to distal GC, while serologically defined SCAG was strongly associated with cardia GC, thus suggesting a divergent risk pattern for these 2 sites.

Gastric cancer screening using the serum pepsinogen test method

The current status of gastric cancer screening, worldwide, as well as in Japan, using the serum pepsinogen test method, was reviewed. We performed a metaanalysis of sensitivity and specificity results from 42 individual studies (27 population-based screening studies: n = 296 553 and 15 selected groups: n = 4 385). Pooled pairs of sensitivity and false-positive rates (FPr) for pepsinogen I level < or = 70 ng/ml; pepsinogen I/II ratio < or = 3, had a sensitivity of 77%/FPr27%. The positive predictive value varied between 0.77% and 1.25%, and the negative predictive value varied between 99.08% and 99.90%. Therefore, we concluded that the definition of the pepsinogen test should include the pepsinogen I/II ratio, as consistency was obtained for both the population-based studies and the selected groups for those studies that used pepsinogen I serum levels together with the pepsinogen I/II ratio for screening for gastric cancer in high-incidence regions other than Japan. Individuals testing positive for extensive atrophic gastritis by serum pepsinogen levels undergo endoscopic examination to test for the presence of gastric cancer. We should increase the efficacy and cost-effectiveness of the gastric cancer screening system, by the identification of groups, at low-risk, as well as those at high-risk, of developing gastric cancer, using a combination of assays of serum Helicobacter pylori antibody titers and the concentration of pepsinogen I and II. In conclusion, the pepsinogen test method can be used as a screening test for high-risk subjects, rather than as a tool for screening for cancer itself. I hope that this pepsinogen test method will become a world standard for gastric cancer prevention in the near future, in other countries, as well as in Japan.

Prevalence of chronic atrophic gastritis in different parts of the world

Chronic atrophic gastritis (CAG) is a well-established precursor of intestinal gastric cancer, but epidemiologic data about its occurrence are sparse. We provide an overview on studies that examined the prevalence of CAG in different parts of the world. Articles containing data about the prevalence of chronic atrophic gastritis in unselected population samples and published until November 2005 were identified by searching the MEDLINE database. Furthermore, the references in the identified publications were screened for additional suitable studies. Studies comprising at least 50 subjects were included. Forty-one studies providing data on the prevalence of CAG in unselected population samples could be identified. CAG was determined by gastroscopy in 15 studies and by pepsinogen serum levels in 26 studies. Although results are difficult to compare due to the various definitions of CAG used, a strong increase with age, the lack of major gender differences, and strong variations between populations and population groups (in particular, relatively high rates in certain Asian populations) could be observed quite consistently. We conclude that CAG is relatively common among older adults in different parts of the world, but large variations exist. Large-scale international comparative studies with standardized methodology to determine CAG are needed to provide a coherent picture of the epidemiology of CAG in various populations. Noninvasive measurements of CAG by pepsinogen levels may be particularly suited for that purpose.

Comparison of prevalence of chronic atrophic gastritis in Japan, China, Tanzania, and the Dominican Republic

PURPOSE

To compare the prevalence of chronic atrophic gastritis (CAG) in Japan, China, Tanzania, and the Dominican Republic and to assess the usefulness of Helicobacter pylori infection and serum gastrin level as markers of CAG.

METHODS

The subjects were volunteers from local communities in Japan (n=859), China (n=1741), Tanzania (n=573), and the Dominican Republic (n=1215). Each individual underwent a health checkup and blood sampling for measurement of serum pepsinogen I and II, pepsinogen I /II ratio, serum gastrin, and H. pylori antibodies, and responded to a questionnaire on upper digestive tract diseases.

RESULTS

The prevalences of H. pylori infection (23.5-96.1%), CAG (5.6-60.4%), and serum gastrin (62.0-136.5 pg/ml) varied by age, sex, and country. Serum gastrin level for men differed in each country according to age. In Tanzanian men, the median gastrin level (101.0 pg/ml) was the highest in the 40 to 49 years age group (p < 0.01) while there was no significant difference among different age groups in Tanzanian women. Serum gastrin level in subjects > or = 70 years was higher than in other age groups in both sexes in the Dominican Republic (males, 92.5, females, 136.5 pg/ml). The prevalence of H. pylori infection increased (p < 0.01) with advancing age in Japan (only for women) and the Dominican Republic but was high in all age groups of both sexes in China and Tanzania. The prevalence of CAG increased (p < 0.01) with age in both sexes in Japan, China (women only), and the Dominican Republic, but not in Tanzania. The odds ratio of CAG in H. pylori infected subjects was 5.3 times that in H. pylori-negative subjects. The odds ratio of CAG increased by 0.6%/1 pg/ml increase in serum gastrin.

CONCLUSIONS

Our results indicated that H. pylori infection, serum gastrin, and advancing age are good markers of CAG and that the prevalence of CAG is the highest in Japan.

Serum levels of interleukin 1beta, interleukin 8 and tumour necrosis factor alpha as markers of gastric cancer

Despite the efforts made, a serum marker reliable for the screening and follow-up of patients with gastric cancer has not yet been identified. The aim of this preliminary study was to test the role of pro-inflammatory cytokines interleukin 1beta, interleukin 8 and tumour necrosis factor alpha in patients with gastric cancer and in control groups. The statistical analysis of cytokines serum levels in the group with gastric cancer versus control groups has shown considerable differences (p < 0.001) in their mean rates. The results indicate that the cytokines interleukin 1beta, interleukin 8 and tumour necrosis factor alpha might perhaps act as diagnostic markers in patients with gastric cancer. Therefore, it is hypothesized that after more extended trials, their use in the screening and prognostic assessment of these patients could be a possibility.

Relationship among serum pepsinogens, serum gastrin, gastric mucosal histology and H. pylori virulence factors in a paediatric population

OBJECTIVE

Serum pepsinogens and gastrin have been proposed as markers of gastritis, but have seldom been studied in children. In this study the aim was to identify host- and Helicobacter pylori-related factors linked to variations in serum gastrin, PGI, PGII, and to evaluate the potential of these biomarkers for diagnosing gastritis, whether H. pylori-associated or not.

MATERIAL AND METHODS

Ninety-two dyspeptic children referred for endoscopy (peptic ulcer exclusion) were included in the study. H. pylori status (urease, culture, histology) was assessed, and genotype determined (PCR) in H. pylori-positive subjects. Serum gastrin, PGI and PGII levels were measured by standard radioimmunoassay (RIA).

RESULTS

PGI and PGII levels were significantly higher in H. pylori-positive subjects (p=0.007; p=0.012, respectively). Gastrin levels were significantly higher in H. pylori-negative subjects (p=0.035). PGI and PGII were associated significantly with higher antrum inflammation scores (p=0.002; p=0.016, respectively); only PGI was associated with age, after controlling for inflammation (p=0.033) and for activity (p=0.037). The contribution of virulence factors could not be assessed owing to the low number of virulent strains. After multivariate analysis, only antrum inflammation was independently associated with PGI level (p=0.012). Receiver operating characteristic (ROC) analysis showed a low PGI and PGII discriminant power for predicting antrum inflammation.

CONCLUSIONS

Pepsinogen levels as measured in this study seem predominantly to reflect antral inflammation, but they are not an effective screening test for gastritis (H. pylori-positive or -negative) in dyspeptic children.

Severity of atrophic gastritis related to antiparietal cell antibody and gastric carcinogenesis, including p53 mutations

BACKGROUND AND AIMS

Infection with Helicobacter pylori (Hp) has been linked to atrophic gastritis, an inflammatory precursor of non-cardia gastric carcinoma. Mutations in the p53 gene are one of the most frequent genetic alterations in gastric carcinoma. In a subgroup of atrophic gastritis, antiparietal cell antibody (APCA) has been detected. This study was aimed to clarify the role of APCA in the progression of atrophic gastritis and gastric carcinogenesis, and to determine the relationship of the severity of atrophic gastritis to gastric carcinoma and to p53 mutations.

METHODS

In 494 control subjects and 284 gastric carcinoma patients, serum APCA was evaluated and all subjects and patients were classified into four groups using serologic markers (anti-Hp IgG antibody and pepsinogen (PG) test: positive; PG I < 70 microg/L and PG I/II ratio < 3.0) as follows: A, HP- PG-; B, HP+ PG-; C, HP+ PG+ and D, HP- PG+. p53 mutations were analyzed in 174 of 284 patients.

RESULTS

Antiparietal cell antibody seropositivity increased from group B to D, however, no difference in its positivity was found between controls and patients. The incidence of gastric carcinoma increased from A to D, especially the intestinal subtype. The frequency of p53 gene mutations was higher in PG+ than in PG- gastric carcinoma.

CONCLUSIONS

Antiparietal cell antibody seropositivity is involved in the progression of a subgroup of atrophic gastritis, but not associated with gastric carcinogenesis. Severe atrophic gastritis is associated with susceptibility to gastric carcinoma, especially the intestinal subtype, and p53 mutations.

Gastric cancer screening using the serum pepsinogen test method

The current status of gastric cancer screening, worldwide, as well as in Japan, using the serum pepsinogen test method, was reviewed. We performed a metaanalysis of sensitivity and specificity results from 42 individual studies (27 population-based screening studies: n = 296 553 and 15 selected groups: n = 4 385). Pooled pairs of sensitivity and false-positive rates (FPr) for pepsinogen I level < or = 70 ng/ml; pepsinogen I/II ratio < or = 3, had a sensitivity of 77%/FPr27%. The positive predictive value varied between 0.77% and 1.25%, and the negative predictive value varied between 99.08% and 99.90%. Therefore, we concluded that the definition of the pepsinogen test should include the pepsinogen I/II ratio, as consistency was obtained for both the population-based studies and the selected groups for those studies that used pepsinogen I serum levels together with the pepsinogen I/II ratio for screening for gastric cancer in high-incidence regions other than Japan. Individuals testing positive for extensive atrophic gastritis by serum pepsinogen levels undergo endoscopic examination to test for the presence of gastric cancer. We should increase the efficacy and cost-effectiveness of the gastric cancer screening system, by the identification of groups, at low-risk, as well as those at high-risk, of developing gastric cancer, using a combination of assays of serum Helicobacter pylori antibody titers and the concentration of pepsinogen I and II. In conclusion, the pepsinogen test method can be used as a screening test for high-risk subjects, rather than as a tool for screening for cancer itself. I hope that this pepsinogen test method will become a world standard for gastric cancer prevention in the near future, in other countries, as well as in Japan.

Why is the hyperplastic polyp a marker for the precancerous condition of the gastric mucosa?

It is well known from the older literature that gastric carcinomas are more likely to develop in a stomach containing hyperplastic polyps. The reason why such a stomach should represent a precancerous condition is, however, largely unexplained. The aim of this study was to determine the disorders of the gastric mucosa in which hyperplastic polyps occur. In 244 patients with hyperplastic polyp, in whom at least two additional biopsies each from the antrum and corpus were available, gastritis was classified on the basis of the updated Sydney System. In none of the 244 patients was the gastric mucosa found to be normal. The most common disorder, at 51.3%, was autoimmune gastritis of the corpus mucosa, while chronic active Helicobacter pylori (Hp) gastritis was seen in 37.3% of the patients. Of the patients with Hp gastritis, 56.1% had corpus-dominant Hp gastritis. Other forms were relatively rare: when A-gastritis, corpus-dominant Hp gastritis and any other form of Hp gastritis were lumped together as a precancerous condition, these changes were found in 88.6% of the patients with hyperplastic polyps of the stomach. In the presence of hyperplastic polyps of the gastric mucosa, additional biopsies obtained from the antrum and corpus should always be performed to obtain a basis for deciding whether to apply Hp eradication treatment as potential carcinoma prophylaxis.

Biomarkers in various types of atrophic gastritis and their diagnostic usefulness

Atrophic gastritis has been shown to involve either the oxyntic gland area, resulting in hypergastrinemia and hypopepsinogenemia I, the antral gland area, causing hypogastrinemia without change in serum pepsinogen I (diffuse antral gastritis; DAG), or the entire gastric mucosa (multifocal atrophic gastritis; MAG), resulting in both hypogastrinemia and hypopepsinogenemia I; and rare atrophic gastritis limited to the oxyntic gland area, with antibodies against oxyntic cells and/or intrinsic factor (autoimmune metaplastic atrophic gastritis; AMAG). This study was performed on 126 patients with various forms of gastritis and on 126 age- and gender-matched controls, who were subjected to endoscopy with biopsy, H. pylori testing (13C-UBT, serology), assays for serum gastrin and pepsinogen I, and testing for basal and pentagastrin-induced gastric acid secretion. The following groups of patients were examined: group I (N = 22), with AMAG; group II (N = 53), with DAG; group III (N = 51), with MAG; and group IV (N = 126), age- and gender-matched controls without gastritis. The following changes were found. In group I very high serum gastrin and very low pepsinogen I were observed, and all patients were achlorhydric and H. pylori negative. In group II, with low serum gastrin and normal pepsinogenemia and gastric chlorhydria, all patients were H. pylori positive. In group III, with lower serum gastrin and lower pepsinogen I levels and reduced chlorhydria, all patients were also H. pylori positive. And all group IV controls, with normal serum gastrin and pepsinogen I and normal gastric acid secretion without antral or fundic gastritis, were H. pylori negative. We conclude that measurements of serum gastrin and pepsinogen I and gastric acid secretion as well as testing for H. pylori infection may be useful in noninvasive diagnosis of various types of atrophic gastritis and in identification of patients with premalignant gastritis and a high risk of gastric cancerogenesis.

Serological markers for gastric atrophy in asymptomatic patients infected with Helicobacter pylori

OBJECTIVE

Atrophic gastritis is a precancerous condition that is commonly caused by chronic Helicobacter pylori (H. pylori) infection. This blinded, controlled study was designed to determine if serum gastrin and pepsinogens were reliable markers of atrophy in asymptomatic patients.

METHODS

One hundred and forty-seven asymptomatic patients underwent endoscopy with multiple gastric biopsies obtained for histology, culture, and rapid urease test. Fasting serum gastrin (total and G-17) and serum pepsinogens (I-II) were determined by standard immunoassays. Gastric atrophy was histologically assessed in accordance with internationally accepted criteria; three main patterns of gastritis were distinguished: (a) nonatrophic gastritis, (b) atrophic antrum-restricted and antrum-predominant gastritis, and (c) corpus-restricted gastritis. Receiving operating characteristic (ROC) analysis was used to determine the best cut-off for each serum test in nonatrophic gastritis versus antrum-restricted/antrum-predominant atrophic gastritis.

RESULTS

No significant differences in serum gastrin and pepsinogens I-II were detected in nonatrophic gastritis versus patients with antrum-restricted/antrum-predominant atrophic gastritis. The positive likelihood ratios for an abnormal serum test to detect antrum-restricted/antrum-predominant atrophy in the gastric body were total serum gastrin 2.13 (95% CI 0.99, 4.6), gastrin-17: 1.55 (95% CI 0.75, 36.17), pepsinogen I: 2.74 (1.4, 5.4), pepsinogen II: 1.74 (1.27, 2.39), and the ratio of pepsinogen I and II: 1.8 (1.2-2.8). Negative likelihood ratios ranged from 0.20 to 0.65.

CONCLUSION

In an asymptomatic population, serum gastrin (total and G-17) and pepsinogens I-II (and their ratio) do not discriminate nonatrophic versus antrum-restricted/predominant atrophic gastritis.

Development and analytical validation of an enzyme linked immunosorbent assay for the measurement of canine gastric lipase immunoreactivity in serum

The objective of this study was to develop and analytically validate an enzyme linked immunosorbent assay (ELISA) for measurement of canine gastric lipase immunoreactivity (cGLI). A sandwich ELISA was developed using canine gastric lipase (cGL) purified from canine stomachs and polyclonal antibodies directed against cGL, raised in rabbits and purified by affinity chromatography. The assay was validated by determination of sensitivity, working range, linearity, accuracy, precision, reproducibility, and the upper limit of the control range by determining the 97.5th percentile of serum cGLI concentration in 74 healthy canines. Sensitivity and working range in serum were 200 ng/L and 200 to 39 160 ng/L, respectively. Observed to expected ratios for dilutional parallelism for 3 serum samples and 3 dilutions ranged from 86.1% to 244.2% (mean +/- standard deviation [s]; 125.4% +/- 48.2%). Observed to expected ratios for spiking recoveries for 3 serum samples and 6 spiking concentrations ranged from 66.4% to 152.5% (mean +/- s; 104.5% +/- 22.9%). Intra-assay and interassay variabilities for 3 different serum samples were 25.5%, 9.4%, and 13.4% and 26.0%, 17.2%, and 14.4%, respectively. The upper limit of the control range for serum cGLI was 662 ng/L. We concluded that the ELISA for cGLI described here is highly sensitive and shows a wide working range. However, the validation characteristics for this assay are suboptimal and below values of approximately 2.000 ng/L the assay is more semiquantitative in nature. Despite its limitations, whether this assay is useful for the diagnosis of canine gastric disorders remains to be determined.

Improvement in serum pepsinogens and gastrin in long-term monitoring after eradication of Helicobacter pylori: comparison with H. pylori-negative patients

BACKGROUND

A decrease in pepsinogen and gastrin levels 1-3 months after Helicobacter pylori eradication is well known. However, few data are available on the long-term progression of these decreases beyond 1 year after eradication, and there has been no investigation into whether pepsinogen and gastrin levels return to normal levels as defined by data from H. pylori-negative patients with dyspepsia.

AIM

We studied the effect of H. pylori eradication on pepsinogen and gastrin levels for more than 1 year, and compared levels to those in H. pylori-negative patients with dyspepsia. We also investigated the effect of H. pylori eradication on the course of atrophic corpus gastritis as reflected by histology, and on PGI levels and PG I/II ratio.

METHODS

We enrolled 172 H. pylori-positive patients with dyspepsia who had undergone successful eradication therapy of more than 1 year's duration and 101 non-treated H. pylori-negative patients with dyspepsia. H. pylori status was assessed at entry and at each endoscopy after eradication by culture, histological results, the rapid urease test and the urea breath test. In both groups, patients were evaluated for fasting serum pepsinogen I and II and gastrin using a radioimmunoassay technique, and underwent detailed histological assessment according to the updated Sydney System.

RESULTS

In the H. pylori-negative patients, mean serum pepsinogen I and II, I/II ratio and gastrin levels were 52.6 +/- 20.8 ng/mL, 9.2 +/- 4.2 ng/mL, 6.0 +/- 1.7 and 53.5 +/- 29.2 pg/mL, respectively. In H. pylori-positive patients with long-term eradication, pepsinogen I and II, I/II ratio and gastrin levels were 81.3 +/- 46.6 ng/mL, 25.9 +/- 17.1 ng/mL, 3.4 +/- 1.3 and 131.9 +/- 130.8 pg/mL, respectively, before treatment. At 1-3 months after eradication, serum pepsinogen I and II levels in the H. pylori-positive patients decreased to levels similar to those in the negative patients, whereas pepsinogen I/II ratio and gastrin levels remained lower and higher, respectively, than in the negative patients. Serum pepsinogen I/II ratio and gastrin levels then became similar between the groups at 12-15 months after eradication. In histological findings, inflammation and neutrophil activity decreased by 1-3 months, and atrophy in the corpus and metaplasia in the antrum decreased by 12-15 months.

CONCLUSION

The results suggest that atrophic corpus gastritis and superficial gastritis are reversible, as indicated by both histological and serological findings in a long-term follow-up study.

'Serological biopsy' in first-degree relatives of patients with gastric cancer affected by Helicobacter pylori infection

BACKGROUND

Relatives of patients with gastric cancer are at increased risk of developing this disease, especially if they are infected by Helicobacter pylori. Moreover, H. pylori-related atrophic gastritis and hypochlorhydria are well-documented risk factors for noncardia gastric cancer. Serum pepsinogen I (sPGI) and II (sPGII) levels are low in this condition. The aim of our study was to assess by means of a 'Gastropanel' blood test, including sPGI, sPGII, gastrin-17 (G-17) and antibodies anti-H. pylori (IgG-Hp). both functional and morphological features of gastric mucosa in Hp + ve subjects with a family history of gastric cancer.

MATERIALS AND METHODS

Twenty-five Hp + ve subjects consecutively referred to our department for gastrointestinal complaints, selected as first-degree relatives of patients suffering from gastric cancer, were enrolled in the study and then matched for sex and age with 25 dyspeptic and Hp + ve subjects with no family history of gastric neoplasia. Blood samples were taken for determination of gastropanel in all patients; in addition, antibodies against CagA were analysed.

RESULTS

No statistically significant differences were detected between the two groups as regards alcohol consumption, coffee intake and smoking habits. Mean sPGI levels in Group A (83.4 +/- 58.4 microg/L) were significantly lower than those in Group B (sPGI 159.5 +/- 80.6 microg/L; P < 0.0001) as well as sPGII (12.5 microg/L = 6.24 versus 20.6 +/- 58 microg/L; P < 0.006). No statistical difference was found between the two groups in relation to G-17 levels, IgG-Hp titres and antibodies against CagA.

CONCLUSION

First-degree relatives of patients with noncardia gastric cancer affected by H. pylori infection present lower sPGI and sPGII levels, possibly due to the increased frequency of atrophic lesions in these patients.

Pepsinogen A, pepsinogen C, and gastrin as markers of atrophic chronic gastritis in European dyspeptics

Serum levels of pepsinogen and gastrin are parameters that can be used as biomarkers for gastric mucosa. The aim of this study was to validate these serum biomarkers, that is pepsinogen A (PGA), pepsinogen C (PGC), PGA/PGC ratio, and gastrin, as screening tests for precancerous lesions: atrophic chronic gastritis (ACG) or Helicobacter pylori-related corpus-predominant or multifocal atrophy. The study population was comprised of a subsample of 284 patients from the 451 included in the Eurohepygast cohort, between 1995 and 1997. The concentrations of PGA, PGC, and gastrin were measured by radioimmunoassays. Histological diagnosis was the gold standard. Cut-off points were calculated using receiving operator characteristics (ROC) curves. Factors linked to variation of biomarkers were identified using multivariate linear regression. The mean of each biomarker in the sample was: PGA, 77.4 microg x l(-1); PGC, 13.2 microg x l(-1); PGA/PGC, 6.7; and gastrin, 62.4 ng x l(-1). For ACG patients, the areas under the PGA, PGC, PGA/PGC, and gastrin ROC curves were 0.55, 0.62, 0.73, and 0.58, respectively. The best cut-off point for PGA/PGC was 5.6, with sensitivity 65% and specificity 77.9%. For H. pylori-related corpus-predominant or multifocal atrophy, the areas under the respective ROC curves were 0.57, 0.67, 0.84, and 0.69. The best cut-off point for PGA/PGC was 4.7, with sensitivity 77.1% and specificity 87.4%. The results suggested that only the PGA/PGC ratio can be considered as a biomarker for precancerous lesions of the stomach, and may be useful as a screening test.

Ratio between serum IL-8 and pepsinogen A/C: a marker for atrophic body gastritis

BACKGROUND AND AIMS

Elevated serum gastrin and a low pepsinogen A/C ratio are well-recognized markers for atrophic body gastritis (ABG). We have shown that the presence of body atrophy is also associated with elevated serum pro-inflammatory cytokines. This study tested the hypothesis that serum cytokines provide additional information to gastrin and pepsinogens in screening for ABG.

METHODS

Two hundred and twenty-six consecutive patients were investigated on referral for upper gastrointestinal endoscopy: 150 were patients with gastro-oesophageal reflux disease, receiving acid inhibitory medication either with proton pump inhibitors (n = 113) or with histamine2-receptor antagonists (n = 37), and 76 were nontreated controls, who had normal endoscopic findings. Gastric mucosal biopsies were sampled for histological examination (Sydney classification). Serum samples were analyzed for gastrin, chromogranin A (CgA), and pepsinogens A and C by RIA, and for the interleukins (IL)-1beta, IL-6, and IL-8 by ELISA.

RESULTS

Subjects with ABG had significantly higher serum gastrin (P < 0.01) and serum CgA (P < 0.01) levels and significantly lower pepsinogen A/C ratios (P < 0.001) than those without ABG. Additionally, serum IL-1beta, IL-6 and, especially, IL-8 levels were significantly higher in the subjects with than in those without ABG (P < 0.0001, for all cytokines). To optimize the detection of body atrophy we defined the ABG index: the ratio between the simultaneously measured IL-8 and pepsinogen A/C. The area under the ROC curve for the ABG index was significantly greater than that for serum gastrin and for serum pepsinogen A/C alone (0.91 +/- 0.029 vs. 0.72 +/- 0.042, and vs. 0.83 +/- 0.031, P = 0.018 and P = 0.049). Using the ABG index at a cut-off value of 1.8 pg mL-1, 91% of the cases were classified correctly.

CONCLUSIONS

The ratio between serum IL-8 and pepsinogen A/C accurately predicts the presence of ABG. We therefore propose the ABG index as a noninvasive screening test for ABG in population-based studies.

Gastric carcinoid tumors without autoimmune gastritis in Japan: a relationship with Helicobacter pylori infection

In Japan, most cases of gastric carcinoid tumor (GCT) are unassociated with either autoimmune gastritis (AIG) showing type-A chronic atrophic gastritis (CAG-A) or Zollinger-Ellison syndrome (ZES). However, the pathogenesis of this tumor remains unknown. Recent studies have determined that Helicobacter pylori infection induces gastric carcinoid in Mongolian gerbils and that H. pylori lipopolysaccharide exerts a mitogenic effect on ECL cells. We examined five patients with histologically diagnosed GCT, 40 patients with H. pylori-positive gastric ulcer (Hp+GU), 24 patients with H. pylori-positive duodenal ulcer (Hp+DU), and 12 patients with AIG showing CAG-A topographically. We compared the prevalence of H. pylori infection, and the levels of gastrin and pepsinogen (PG) in the serum of patients with GCT with those of patients with Hp+GU, or Hp+DU, and AIG. We also investigated the histological characteristics of the tumor and the gastric corpus mucosa in the GCT patients. The levels of serum gastrin and PG I and II were measured using an RIA kit. In all five (100%) patients with GCT, H. pylori infection was present, without any evidence of AIG or ZES. The serum levels of gastrin in the GCT patients were higher than those in either Hp+GU or Hp+DU patients and lower than those in the AIG patients. In contrast, serum PG I levels and the PG I/II ratio were lower in the GCT group than in the Hp+GU or Hp+DU groups. Histologically, all GCTs were ECL cell tumors and peritumoral corporal mucosal atrophy was observed in four of the five patients with GCT. In conclusions, H. pylori infection and hypergastrinemia were found in the patients with GCT without AIG. This finding suggests that H. pylori infection may induce corporal mucosal atrophy and hypergastrinemia that can produce a GCT with time.

The prevalence of Helicobacter pylori infection in benign laryngeal disorders

Helicobacter pylori (HP) is an accepted cause of chronic active gastritis and has a major causative role in peptic ulcers. It is a gastric carcinogen. Its role in nonulcer dyspepsia (NUD) is less clear, yet 50% of patients with NUD are infected with HP, and some recent literature demonstrates long-term improvement of symptoms following eradication. HP has been investigated in several other organ systems, but has not been investigated to any major degree in laryngeal disorders, a region that could be directly exposed to the bacterium from pharyngolaryngeal reflux. This study represents one arm of a larger study designed to investigate such a relationship. Of 101 patients with nonmalignant voice disorders presenting to our voice clinics, 54.5% tested positive for the H. pylori organism. Of the controls, 47.1% tested positive. When striated into age groups of < 45 years, 46-61 years, and > 62 years, and then age-matched with the controls, the likelihood of infection with the H. pylori organism was greater in both the experimental middle group, and in the middle group when combined with the elder group, than in the matched controls, and this difference demonstrated a trend approaching statistical significance. This finding is discussed in the light of other studies on HP and on gastroesophageal reflex (GER).

Variation in serum pepsinogens with severity and topography of Helicobacter pylori-associated chronic gastritis in dyspeptic patients referred for endoscopy

BACKGROUND

It has long been recognised that specific patterns of gastritis are linked with different gastroduodenal diseases and that serum pepsinogens vary with the histological state of the gastric mucosa. With the discovery of the role of Helicobacter pylori in chronic gastritis and the availability of noninvasive tests for H. pylori infection, individuals with H. pylori gastritis can now be identified without endoscopic biopsy. However, without a knowledge of the pattern and severity of gastritis it is impossible to predict the likelihood of significant associated gastroduodenal pathology.

AIMS

The aim of this study was to evaluate the diagnostic potential of serum pepsinogens I and II in predicting the topography and severity of gastritis in H. pylori-infected dyspeptic patients attending for endoscopy.

METHODS

Fasting serum was obtained from consecutive dyspeptic patients attending for endoscopy, and pairs of gastric biopsies obtained from the mid-body and antrum. Gastritis was graded according to the Sydney System, and serum pepsinogen levels determined by radio-immunoassay.

RESULTS

Sixty-nine dyspeptic patients were studied (mean age: 49.6 years) of whom 34 had H. pylori-associated chronic gastritis (Hp-gastritis) - antral predominant gastritis (APG) in 41.2%, pangastritis (PAN) in 52.9%, and corpus predominant (CPG) in 5.9%. Serum pepsinogen II levels were significantly higher, and the serum pepsinogen I : II ratio significantly lower, in the H. pylori positive group than in other groups. Within the Hp-gastritis group, there was a step-wise decrease in serum pepsinogen I levels with progression from APG through PAN to CPG pattern (a cut-off value of > or = 100 ng/ml would have identified APG with a positive predictive value of 77%, though with low sensitivity). Within the Hp-gastritis group, serum pepsinogen I and II levels were correlated with antral chronic inflammation score and serum pepsinogen II levels also with antral activity score. Serum pepsinogen I and the pepsinogen I : II ratio were lowest in severe gastric corpus atrophy.

CONCLUSION

In dyspeptic patients known to be infected with H. pylori, serum pepsinogen values provide an assessment of the overall topography of gastritis, the severity of antral inflammation and the presence of severe corpus atrophy.

Review article: the cost of diagnosing Helicobacter pylori infection

Non-invasive testing and treatment for Helicobacter pylori has been recommended for dyspeptic patients in primary care and a number of recent studies have demonstrated the cost-effectiveness of this approach. As the prevalence of H. pylori infection declines, the positive and negative predictive values of individual tests will change. Cost-effectiveness is important in determining the appropriate test in individual populations. Recent studies have shown that the stool antigen test and the urea breath test have high sensitivity and specificity in the detection of H. pylori infection before and after therapy. Cost-effectiveness studies have shown that when the prevalence of H. pylori infection is low or intermediate, serological tests have relatively poor accuracy compared with the stool test or the urea breath test. In populations with low or intermediate prevalence (<60%) these tests should be preferred to ELISA serology or office-based whole-blood test or serology. This is particularly true when the prevalence of H. pylori infection is less than 30% as is seen in many developed countries. When the prevalence of H. pylori infection is high (>60%), low-cost antibody tests are cost-effective.

Effect of smoking on serum pepsinogen I level depends on serological status of Helicobacter pylori

Serum pepsinogen (sPG) levels are used in gastric cancer screening programs. However, modification of sPG levels by smoking habit, according to the status of Helicobacter pylori (H. pylori) infection has been little investigated. This study investigated the effects of smoking on serum levels of pepsinogen I (PG I), pepsinogen II (PG II), and gastrin by IgG titer of antibody against H. pylori (Hp-IgG titer) using the data from 356 current-smokers and 262 non-smokers (133 never-smokers and 129 ex-smokers) in a cross-sectional study of 618 men aged 40 to 49 years. PG I, PG II, PG I / PG II ratio and gastrin were significantly associated with Hp-IgG titer in never-smokers [Spearman's correlation coefficient (95% confidence interval): 0.23 (0.07, 0.39), 0.52 (0.41, 0.63), -0.40 (-0.54,-0.27), and 0.25 (0.10, 0.41), respectively]. However, the correlation coefficients of PG I and PG II decreased in current-smokers, 0.02 (-0.1, 0.13) and 0.32 (0.22, 0.42), respectively. In H. pylori seronegative and low titer cases, the mean PG I level was significantly (P < 0.01) higher in current-smokers, compared with non-smokers. However, in high titer cases, the mean PG I level was lower in current-smokers. Mean PG II and gastrin levels, and PG I / PG II ratio did not differ according to smoking habits by Hp-IgG titer. The gastrin level was significantly correlated with PG II, but not PG I. These data indicate that current smoking influences the serum PG I level depending on Hp-IgG titer and the associations between sPGs and Hp-IgG titer. Gastrin is not involved in the modification of PG I levels by smoking.

Implications of serum pepsinogen I in early endoscopic diagnosis of gastric cancer and dysplasia. Helsinki Gastritis Study Group

BACKGROUND AND AIMS

The risk of gastric cancer (GCA) is increased in atrophic gastritis. A low serum pepsinogen group I (SPGI) level is a good serologic indicator of atrophic gastritis of the gastric corpus and fundus, and can be used for diagnosis of subjects with atrophic gastritis and of increased risk for GCA. The present study was undertaken to investigate whether SPGI assay and a diagnostic gastroscopy could enable the diagnosis of GCA at an early stage.

MATERIAL AND METHODS

The study was carried out as part of the Alpha-Tocopherol, Beta-Carotene Cancer prevention study (ATBC study) in Finland, in which 22,436 male smokers aged 50-69 years were screened by SPGI. Low SPGI levels (< 25 microg/l) were found in 2196 (9.8%) men. Upper GI endoscopy (gastroscopy) was performed in 1344 men (61%) and 78% of these had moderate or severe atrophic corpus gastritis in endoscopic biopsies. A control series of 136 men from the ATBC study cohort with abdominal symptoms, but with SPGI > or = 50 microg/l were similarly endoscopied, and 2.2% of these had corpus atrophy.

RESULTS

Neoplastic alterations were found in 63 (4.7%; 95% CI: 3.6%-5.8%) of the 1344 endoscopied men with low SPGI levels. Of these, 42 were definite dysplasias of low grade, 7 dysplasias of high grade, 11 invasive carcinomas, of which 7 were 'early' cancers, and 3 carcinoid tumors. In the control series, 1 man (0.7%) of the 136 men had a definite low-grade dysplasia. Thus, 18 (1.3%; 95% CI 0.7%-2.0%) cases with 'severe' neoplastic lesions (4 advanced cancers, 7 early cancers and 7 dysplasias of high grade) were found in the low SPGI group, but there were none in the control group. All four patients with advanced cancer died from the malignancy within 5 years (mean survival time 2.5 years), whereas surgical treatment in all those with early cancer or high-grade dysplasia was curative. One of the seven patients with early cancer and two of the seven with high-grade dysplasia died within 5 years, but none died from the gastric cancer. Thus, curative treatment was given to 14 of 18 men in whom a malignant lesion was found in gastroscopy. This is about 15% of all gastric cancer cases (92 cases) which were diagnosed within 5 years after SPGI screening in the 22,436 men. Among the gastric cancer cases of the main ATBC study, the 5-year survival rate was 33% (85% of the non-survivors died from gastric cancer).

CONCLUSIONS

We conclude that assay of SPGI followed by endoscopy is an approach which can enable the early diagnosis of gastric cancer at a curable stage.

Evaluation of blood tests to predict normal gastric mucosa

BACKGROUND

To determine the accuracy of blood tests in predicting normal gastric mucosa confirmed by histological examination of gastric biopsy specimens.

METHODS

In total, 207 consecutive patients referred for upper endoscopy were included. Two biopsy specimens each from the antrum and corpus were assessed histologically for the presence of Helicobacter pylori, gastritis, and atrophy. Serum samples were studied for H. pylori antibodies by enzyme immunoassay (Pyloriset EIA-G and EIA-A) and by a rapid latex agglutination test (Pyloriset Dry); pepsinogen I was measured by an immunoenzymometric assay (Gastroset PGI), gastrin by radioimmunoassay, and parietal cell antibodies by indirect immunofluorescence.

RESULTS

In 101 (49%) of 207 patients, the gastric mucosa on histologic examination was normal. In the 63 patients aged 45 years or less, H. pylori IgG serology was negative in all 47 patients with normal gastric mucosa and none had low serum pepsinogen I levels. Among 144 patients over age 45 years, 72 had negative H. pylori IgG serology. Combining the serum pepsinogen I assay with the results of H. pylori IgG serology, 12 patients with normal serology but low serum pepsinogen I were found. Thus, 60 patients, 52 of whom showed normal gastric histology, had normal IgG serology and serum pepsinogen 1. In the remaining eight patients with normal blood tests, the histologic changes were very mild.

CONCLUSIONS

Although negative H. pylori IgG serology alone in younger patients, and in combination with normal serum pepsinogen I levels in older patients, reliably predicted the presence of normal gastric mucosa, gastroscopy is still recommended for patients over 45 years.

The cost-effectiveness of diagnostic testing strategies for Helicobacter pylori

OBJECTIVE

Several noninvasive methods are now available for diagnosing Helicobacter pylori infection. Because the prevalence of H. pylori infection is variable in patients requiring testing, the optimal testing strategies may vary under different conditions. The aim of this study was to evaluate the cost-effectiveness of competing diagnostic strategies for H. pylori in patients with varying H. pylori prevalence.

METHODS

A decision analysis was performed comparing the costs per number of correct diagnoses achieved by alternative sequential testing strategies. Estimates of H. pylori prevalence and test characteristics were derived from a systematic review of the MEDLINE bibliographic database. Cost estimates were derived from the 2000 Medicare Fee Schedule.

RESULTS

The enzyme-linked immunosorbent assay (ELISA) test had the lowest cost per correct diagnosis at low (30%), intermediate (60%), and high (90%) prevalence ($90-$95/correct diagnosis), but its diagnostic accuracy was low (80-84%). At low and intermediate prevalence the stool test was more accurate (93%), with an average cost of $126-$127 per correct diagnosis. Additional confirmatory testing of positive or negative tests increased the diagnostic accuracy of the stool test, but had high incremental costs. ELISA testing was preferable when prevalence rates were very high (90%), and using a confirmatory urea breath test for negative ELISA tests increased the diagnostic accuracy to 96%, with modest incremental costs. If the cost of the breath test was <$50 or if the cost of the stool test is >$82, breath testing became preferable to stool testing. If the cost of the stool test fell to <$20, it became preferable to ELISA. Similarly, if the cost of the ELISA serology was >$39 then stool testing became preferable at all prevalence rates. Fingerstick whole blood tests were not cost-effective.

CONCLUSIONS

The choice of an initial test for H. pylori detection depends on the prevalence of H. pylori infection and the value placed on increased diagnostic accuracy. Although ELISA results in the lowest cost-effectiveness ratios, in patients at low-intermediate pretest probability of infection, the stool test provides increased accuracy, with modest incremental costs.

Serologic screening before endoscopy: the value of Helicobacter pylori serology, serum recognition of the CagA and VacA proteins, and serum pepsinogen I

BACKGROUND

We wanted to assess the diagnostic value of pre-endoscopy screening by Helicobacter pylori serology, serum recognition of the CagA and VacA proteins, and serum pepsinogen I levels (sPGI) in patients up to 55 years of age with uncomplicated simple dyspepsia.

METHODS

Consecutive dyspeptic patients referred for open-access endoscopy, excluding patients with alarm symptoms, recent intake of acid suppressants, or ingestion of non-steroidal anti-inflammatory drugs. H. pylori status was determined by histology and urease testing. H. pylori serologic status was determined with the enzyme-linked immunosorbent assay (ELISA) and Western blotting, serum recognition of CagA and VacA with Western blot, and sPGI levels by radioimmunoassay.

RESULTS

One hundred and fifteen patients were studied (mean age, 40 years: range, 20-55 years), of whom 58 were H. pylori-positive in biopsy-based tests. Twenty-one patients (18%) had significant gastroduodenal lesions (erosions, ulcers, or cancer). The sensitivity (specificity) of the ELISA (optimized) and Western blot in determining H. pylori status was 94.8% (89.5%) and 100% (96.4%), respectively. Screening strategies based on the ELISA or Western blot for determining H. pylori serologic status would have detected 95% or 100% of significant lesions, respectively, and each 'saved' 47% of endoscopies for simple dyspepsia. Serum recognition of the CagA protein would have detected 95% of significant lesions and 'saved' 55% of endoscopies, whereas recognition of the VacA protein would have detected only 81% of the lesions. Screening by H. pylori serology plus a 'low' (<55 ng/ml) or 'high' sPGI (>125 ng/ml) would detect only 57% of significant lesions, although the only case of cancer was included in the hypopepsinogenaemic subgroup of just 11 patients.

CONCLUSIONS

In patients with uncomplicated, simple dyspepsia up to 55 years of age, screening by H. pylori serology identified 95%-100% of patients with significant gastroduodenal lesions while potentially saving 46.9% of endoscopies. Serum recognition of the CagA protein identified 95% of lesions and would have saved an additional number of endoscopies (7.9%) compared with basic serology. Measurement of sPGI was of limited diagnostic value.

Helicobacter pylori genotypes influence serum pepsinogen C levels

BACKGROUND

Infection from Helicobacter pylori significantly influences pepsinogen A (PGA) and C (PGC) levels in serum. Increased PGA and PGC serum levels are observed in H. pylori positive patients, while a significant decrease is observed after eradication. Little is known about the relative role of H. pylori cytotoxic strains in this phenomenon. The aim of our study was to assess the influence of cagA genotype on circulating levels of PGA and PGC.

MATERIALS AND METHODS

We studied 81 consecutive H. pylori positive patients, 64 H. pylori negative patients and 18 healthy controls. H. pylori was evaluated histologically in two antral and two body biopsies (Giemsa and/or Warthin Starry staining). Extracted DNA was then submitted for PCR amplification of both the urease A and cagA genes. A serum obtained from each patient before endoscopy was used for specific radioimmunoassay measurement of PGA and PGC.

RESULTS

The urease A gene was found in all H. pylori positive patients, the cagA gene was detected in 55 H. pylori positive patients and in none of the H. pylori negative patients. PGA and PGC levels were significantly higher in H. pylori positive than in H. pylori negative patients. A significant association was found between cagA and raised serum PGC levels in patients with antral gastritis but not in patients with peptic ulcer. Serum PGA levels were not affected by cagA.

CONCLUSIONS

Our results indicate that cagA positivity may influence the circulating PGC levels, probably because it causes a higher grade of mucosal inflammation.

Is the study of human cancer-associated factors, the best or the only model for human carcinogenesis research? I. The question of Helicobacter pylori infection as an accused human gastric carcinogen

Experimental carcinogenesis has discovered and analyzed the inductive effect for one type of cancer, of single factors in given animal strains. Human carcinogenesis analyses the effect of associated factors on one cancer type incidence. It does not find any direct correlation and finds a lot of intermediary effects and mechanism between the factor and established carcinogenesis. Regarding Helicobacter pylori (HP), one realizes there is no statistical correlation between gastric infection and carcinoma. The only data which sustain its role is its possible effect in promoting atrophic gastritis with intestinal metaplasia, via the serum pepsinogen 1 reduction due to anti-HP immunoglobulin A (IgA) antibody. Intestinal metaplasia of the stomach is a condition increasing cell proliferation.