Serum pepsinogen levels indicate the requirement of upper gastrointestinal endoscopy among Group A subjects of ABC classification: a multicenter study

Factors Predicting Effectiveness of Eradication Therapy for Helicobacter pylori-Associated Dyspepsia Symptoms

Functional dyspepsia is distinguishable from Helicobacter pylori-associated dyspepsia. However, distinguishing H. pylori-associated dyspepsia from functional dyspepsia before H. pylori eradication is difficult. Therefore, in the present study, we aimed to investigate whether serum pepsinogen levels before H. pylori eradication are associated with the amelioration of dyspepsia after successful H. pylori eradication. Additionally, we examined the usefulness of serum pepsinogen levels and other factors in predicting dyspepsia outcomes. H. pylori eradication was effective in 14 patients (Responders) and ineffective in 19 patients (Non-responders). The pepsinogen I/II ratio in Responders (3.4 ± 1.2) and Non-responders (2.3 ± 1.0) differed significantly (p = 0.006). The optimal cut-off pepsinogen I/II value was 2.3. Multivariate logistic regression analysis showed that the adjusted odds ratio for Non-responders was 26.1 (95% confidence interval: 2.0-338.0, p = 0.012) for a pepsinogen I/II ratio ≤ 2.3 and 8.10 (95% confidence interval: 1.1-57.6, p = 0.037) for smoking habits. The pepsinogen I/II ratio and smoking habits were associated with the effects of H. pylori eradication on dyspeptic symptoms. Thus, the pepsinogen I/II ratio cut-off value can be used to identify patients likely to respond to H. pylori eradication after the resolution of dyspeptic symptoms.

Gastric cancer detection rates using GI endoscopy with serologic risk stratification: a randomized controlled trial

BACKGROUND AND AIMS

Efforts have been made to develop an endoscopic screening system incorporating serologic gastric cancer (GC) risk stratification (ABC classification) alongside annual population-based GC screening using barium. We conducted a randomized controlled trial (RCT) to compare GC detection rates between the Ba-Endo group, which underwent annual barium tests for primary screening followed by detailed endoscopic examinations, and the ABC-Endo group, where endoscopy intervals were determined based on individual gastric cancer risk in the ABC classification.

METHODS

In total, 1206 individuals from Yurihonjo and Nikaho City, Akita Prefecture, were randomized through the minimization method using sex and age as allocation factors. The intervention study was conducted for both groups over 5 years. The Ba-Endo group received annual barium tests, and the ABC-Endo group underwent EGD at different intervals: group A, EGD only at entry; group B, EGD once every 3 years; group C, EGD once every 2 years; and group D, EGD every year.

RESULTS

There were 24 detected GC lesions, with a GC detection rate of 1.9%. GC detection rates in the Ba-Endo and ABC-Endo groups were 2.0% and 1.8%, respectively, with no significant differences between groups (P = 1.0). However, the rate of GC cured by endoscopic resection alone was 41.6% in the Ba-Endo group and was significantly higher at 90.9% in the ABC-Endo group (P = .02).

CONCLUSIONS

There were no differences between the Ba-Endo and ABC-Endo groups in GC detection rates. However, the rate of detected GCs that could be cured by endoscopic resection alone was significantly higher in the ABC-Endo group. (Clinical trial registration number: UMIN000005962.).

Clinical Characteristics of Patients With Previous Helicobacter pylori Infection-Induced Atrophic Gastritis

AIMS

Patients with atrophic gastritis unrelated to autoimmune gastritis (AIG) and without active Helicobacter pylori (H.pylori) infection or previous eradication therapy are considered to have previous Helicobacter pylori infection-induced atrophic gastritis (PHIG). This study aimed to clarify the clinical characteristics of patients with PHIG.

METHODS

Consecutive patients who underwent upper gastrointestinal endoscopy during the study period were enrolled in the study. Pepsinogen and gastrin levels, H. pylori serology, and endoscopic atrophic grade were assessed. Patients were divided into five groups based on their H. pylori status and disease history (PHIG, without H. pylori infection, with active H. pylori infection, with successful H. pylori eradication, and AIG). Their gastric cancer risk status was classified according to the ABC method of serological gastric cancer screening.

RESULTS

Of 536 consecutive patients who underwent upper gastrointestinal endoscopy during the study period, 318 were included (31 with PHIG, 77 without H. pylori infection, 101 with active H. pylori infection, 80 with successful H. pylori eradication, and 29 with AIG). Of the 31 patients with PHIG, 21 (68%) were H. pylori-seronegative, and 20 (65%) were classified as group A (normal pepsinogen, H. pylori-seronegative). Patients with PHIG accounted for 90.1% of the patients at high risk for gastric cancer misclassified as group A. The pepsinogen and H. pylori serological profiles of patients with PHIG were similar to those of patients with successful H. pylori eradication more than six years previously. A receiver-operating characteristic curve (ROC) analysis that included 13 patients with AIG and without active H. pylori infection and no previous eradication therapy and 31 patients with PHIG revealed that an endoscopic atrophy grade of O-III or greater according to the Kimura-Takemoto classification can predict AIG.

CONCLUSIONS

Two-thirds of the patients with PHIG were misclassified as being at low risk (group A) according to the ABC method, suggesting that endoscopy is necessary for group A patients. The results of the serological evaluation of PHIG indicated that patients with PHIG may have experienced spontaneous H. pylori eradication, possibly because of the use of antibiotics for other conditions. Autoimmune gastritis should be considered in the presence of grade 0-III or greater gastric mucosal atrophy in patients with suspected PHIG, even if the autoantibody and histological findings are not available.

Development of a modified ABC method among Helicobacter pylori infected but serum pepsinogen test-negative individuals

BACKGROUND

Although the ABC method for gastric cancer (GC) screening has been widely adopted in Japan, it may not be suitable for other countries due to population heterogeneity and different tumor histology. We aim to develop a modified ABC method to improve GC screening performance, especially among Helicobacter pylori (Hp) infected but serum pepsinogen (sPG) test-negative individuals.

METHODS

A total of 4745 participants were recruited from Tianjin, China, and were classified into four groups by combined assay for Hp infection and sPG concentrations: Group A (Hp [-], PG [-]), Group B (Hp [+], PG [-]), Group C (Hp [+], PG [+]), and Group D (Hp [-], PG [+]). We used receiver-operating characteristic (ROC) curves analysis and minimum p value method to determine the optimal cutoff point for PG II in Group B. We performed logistic regressions to examine the risk of GC across different subgroups. In addition to the derivation set, the performance of the modified ABC method was also evaluated in an external set involving 16,292 participants from Liaoning, China.

RESULTS

In the modified ABC method, we further classified Group B as low-risk (Group B1) and high-risk subgroups (Group B2) using optimal sPG II cutoff point (20.0 ng/mL) by ROC curves analysis and minimum p value method. Compared with Group B1, Group B2 had a significantly higher risk of GC (adjusted OR = 2.54, 95% CI = 1.94-3.33). The modified ABC method showed good discrimination for GC (AUC = 0.61, 95% CI = 0.59-0.63) and improved risk reclassification (NRI = 0.11, p < .01). Similar results were observed in the validation dataset.

CONCLUSIONS

The modified ABC method can effectively identify high-risk population for GC among Hp-infected but sPG test-negative participants in China.

The Optimal Cut-off of the Latex Immunoassay (LZ Test) for Helicobacter pylori Infection Based on the Stool Antigen Test and Helicobacter pylori-associated Gastritis

Objective Helicobacter pylori antibody kits using the latex immunoassay (LIA) are widely used in Japan. However, the optimal cut-off of the LIA remains unclear. This study clarified the optimal cut-off of the LIA for assessing the current infection status of patients (currently infected, never infected, spontaneously eradicated) in clinical practice. Methods In total, 482 subjects with no history of H. pylori eradication therapy who underwent a medical examination at our hospital were enrolled. The infection status was ascertained using a stool antigen test, and the endoscopic findings of H. pylori-associated gastritis. H. pylori antibody levels were measured using the LIA. Results In total, 414, 38, and 30 subjects were categorized into the never-infected, currently infected, and spontaneously eradicated groups. The optimal cut-off based on receiver operating characteristic curve analysis was 4 U/mL, whereas the area under the curve, sensitivity, and specificity for differentiating never-infected and currently infected subjects were 0.95, 92.1%, and 94.7%, respectively. When applying the cut-off of 4 U/mL to the judgment of current infection in all subjects, the sensitivity and specificity were 92.1% and 92.6%, respectively. Conclusion Our findings suggest that 4 U/mL was the optimal cut-off for differentiating current infection from no prior infection, and the value may be stable because of the exclusion of subjects with spontaneous eradication. The cut-off may be useful in initial screening for current H. pylori infection.

Serum Assay Findings after Successful Helicobacter pylori Eradication

Serum pepsinogen (PG), anti-Helicobacter pylori (H. pylori) immunoglobulin G (IgG), and gastrin-17 (G-17) are plasma biomarkers for gastritis. H. pylori serology titers and PG levels increase during active H. pylori infection; moreover, elevated PG II levels indicate a high risk for diffuse-type gastric cancer in East Asian populations. Serum PG I/II ratios and PG I levels decrease with the progression of gastric corpus atrophy; thus, a combination of serum PG I levels ≤70 ng/mL and a PG I/II ratio ≤3 (serologic atrophy) indicates a high risk of intestinal-type gastric cancer. Serum G-17 is often not used as an indicator in H. pylori-seroprevalent populations because it is usually elevated in subjects with H. pylori infections. When H. pylori is eradicated, most patients show a rapid decrease in serum PG II levels and anti-H. pylori IgG titers within a few months. Seroreversion is required for several months to years after regression of H. pylori. Moreover, seroreversion may not always be achieved in all eradicated cases. The serum PG I/II ratio starts to increase after eradication; therefore, serologic atrophy improves accordingly, unless severe atrophy is present. Thus, some eradicated patients may show normal serum assay findings but have a higher risk for developing gastric cancer than H. pylori-naive subjects. Furthermore, serum PG levels decrease after gastrectomy and increase with the intake of certain drugs (e.g., aspirin or acid suppressants) or in renal failure patients. Due to such wide variations, serum assays are inadequate for the confirmation of H. pylori eradication. It is useful when interpreted with gastroscopy and other H. pylori test findings.

Scoring model for discriminating gastric cancer risk in patients with negative serum pepsinogen and anti-Helicobacter pylori antibody results

BACKGROUND

The ABC test measures serum pepsinogen and anti-Helicobacter pylori IgG antibody levels to predict precancerous conditions in the stomach and gastric cancer. However, a limitation of this test is that the gastric cancer risk is not negligible in patients with a negative result.

METHODS

Based on their ABC results, 1157 patients were classified into Groups A (n = 392), B (n = 479), C (n = 247), and D (n = 39). In Group A, 24.2% of patients had atrophic gastritis and/or intestinal metaplasia and had thus been incorrectly assigned to Group A. Patients in Group A were then assigned to derivation (n = 236) and validation (n = 156) cohorts by 3:2 random sampling. Logistic regression analyses were performed to identify the factors discriminating between a correct (true) and incorrect (false) Group A classification.

RESULTS

A 4-point discriminative model was constructed based on a high-negative H. pylori IgG antibody titer and the patient's age (50-64 and ≥65 years). The areas under the receiver operating characteristic curve for the derivation and validation cohorts were 0.868 and 0.894, respectively. In the validation cohort, the addition of a discriminative model score ≥2 to the ABC method showed a similar accuracy for predicting gastric cancer risk compared with the ABC method alone (93.8% vs. 92.4%).

CONCLUSION

The 4-point discriminative model may help identify patients with a normal serological test who are nonetheless at risk of developing gastric cancer.

What Is New in Helicobacter pylori Diagnosis. An Overview

Helicobacter pylori infection remains one of the most prevalent infections worldwide, especially in low-resource countries, and the major risk factor for peptic ulcer and gastric cancer. The “test-and-treat” strategy is recommended by several guidelines and consensus. The choice of testing method is based on patient age, presence of alarm signs and/or symptoms, use of non-steroidal anti-inflammatory drugs, as well as local availability, test reliability, and cost. Culture is the gold standard to detect H. pylori and, possibly, to perform susceptibility testing, however, it requires upper endoscopy and dedicated labs. Recent advances in molecular biology have provided new strategies in detecting infection and antimicrobial resistance without invasive tests. In this review we attempt to offer a comprehensive panorama on the new diagnostic tools and their potential use in clinical settings, in order to accomplish specific recommendations.

Prediction of true Helicobacter pylori-uninfected status using a combination of age, serum antibody and pepsinogen: Logistic regression analysis

Introduction

To prevent gastric cancer, it is important to accurately determine the presence of Helicobacter pylori (HP) infection. However, correctly identifying HP-uninfected individuals is difficult when using the combination of HP antibody and pepsinogen (PG).

Objective

The aim of this study was to discriminate true HP-uninfected individuals from others without the need for endoscopic examination.

Methods

A total of 684 subjects with no history of HP eradication who underwent a medical checkup at our hospital were enrolled. The “true uninfected individuals” were determined by a negative stool antigen test and no endoscopic findings of HP-associated gastritis. HP antibody was measured by the latex immunoassay method. Logistic regression analysis using a combination of noninvasive parameters was performed to develop a formula for predicting true uninfected individuals.

Results

A total of 528 subjects were classified as true uninfected individuals. Logistic regression analysis showed that statistically significant factors for true uninfected individuals were age (p < 0.001), HP antibody (p <0.001), PGI (p <0.001), and PGII (p = 0.012). The areas under the curve (AUCs) for true uninfected individuals were the highest (0.944) upon applying the prediction formula including four parameters: age, HP antibody, PGI, and PGII. Both the sensitivity and the specificity of the four-parameter prediction formula were higher than those of the traditional three-parameter model using HP antibody, PGI, and PGI/II ratio (sensitivity: 93.2% vs. 86.6% and specificity: 88.5% vs. 82.7%).

Conclusions

Our findings suggest that a model with a combination of four noninvasive parameters is useful for predicting true HP-uninfected individuals without the need for endoscopic examination.

Optimized diagnosis of Helicobacter pylori and tailored eradication therapy for preventing gastric cancer: a proposal for SHAKE strategy

INTRODUCTION

To decrease gastric cancer-related mortality, the Korean National Cancer Screening Program provides biennial screening gastroscopy to all individuals aged >40 years. However, a test-and-treat strategy of Helicobacter pylori for preventing gastric cancer has not been established.

AREAS COVERED

In this review, we present up-to-date results of endoscopic findings of H. pylori gastritis, optimal sites for H. pylori detection, gastric cancer risk assessment using serum pepsinogen, tailored eradication based on the antimicrobial resistance against H. pylori, and post-eradication surveillance.

EXPERT OPINION

Here we propose approaches to H. pylori diagnosis and treatment for preventing gastric cancer, termed 'Screening for H. pylori in Korea and Eradication (SHAKE)' strategy. This strategy consists of the following: (1) optimized H. pylori diagnosis, (2) individualized management based on the H. pylori infection status, and (3) tailored eradication therapy. H. pylori gastritis can be diagnosed by endoscopic observation of the gastric mucosal pattern at the greater curvature of the corpus. Measurement of the serum pepsinogen I/II ratio is useful for assessing the risk of gastric cancer. As a first-line treatment, tailored eradication based on the results of molecular testing is effective in a country with a high rate of clarithromycin-resistant H. pylori.

Lifestyle Factors Rather Than Helicobacter pylori Infection or Estradiol Level are Associated With Osteopenia in Japanese Men

Although decreased calcium absorption, decreased bone formation, alcohol drinking, and smoking have been considered as causes of osteopenia in men, the cause is unknown in half of the cases. Many reports highlighted the association between Helicobacter pylori infection and osteoporosis, mainly in East Asia and Japan. To identify relevant factors of osteoporosis in men, we examined estrogen and calcium intakes and other lifestyle factors together with gastric mucosal atrophy caused by Helicobacter pylori infection. This study is a cross-sectional study design of 268 healthy men who underwent general medical examinations. Multivariate analysis was performed, with age, body mass index, smoking habit, drinking habit, exercise habit, estradiol level, calcium intake, and Helicobacter pylori infection and its associated gastric mucosal atrophy as the independent variables and the presence of osteopenia as the dependent variable. The adjusted odds ratio was 0.74 (95% Confidence Interval [0.29, 1.90], p = .531) and 1.31 (95% Confidence Interval [0.54, 3.21], p = .552), when Helicobacter pylori infection was positive without and with gastric mucosal atrophy, respectively. Helicobacter pylori infection and gastric mucosal atrophy were not significant factors. Low body mass index, smoking habit, and low calcium intake were significantly associated with decreased bone density. In conclusion, Helicobacter pylori infection was not a significant risk, whereas low body mass index, current smoking, and lower calcium intake had a significant influence on the development of osteopenia in men.

ABC Classification Is Less Useful for Older Koreans Born before 1960

Background/Aims

In the ABC classification system, group A consists of seronegative subjects without gastric corpus atrophy. This study aimed to determine the prevalence and characteristics of pseudo group A subjects.

Methods

Group A subjects were identified among consecutive Korean adults who underwent a serum anti-Helicobacter pylori immunoglobulin G (IgG) test and pepsinogen (PG) assay on the day of endoscopy. Past infection was defined as the presence of either eradication history or endoscopic findings suggesting past infection (i.e., gastric xanthoma, metaplastic gastritis, or advanced atrophy >closed-type 1).

Results

Among 2,620 group A subjects, 448 (17.1%) had eradication history, and 133 (5.1%) showed endoscopic findings suggesting past infection. Older age (odds ratio [OR], 1.148; 95% confidence interval [CI], 1.067 to 1.236) and earlier year of birth (OR, 1.086; 95% CI, 1.009 to 1.168) were independent risk factors for classification into pseudo group A, with cutoff points at 50.5 years and birth year of 1959.5, respectively. Positive H. pylori test findings were found in 22 subjects (3.1%) among the 715 subjects who underwent the urea breath test or Giemsa staining on the same day. Current infection was positively correlated with PG I and PG II levels (p<0.001) but not with age, anti-H. pylori IgG titer, or classification into pseudo group A.

Conclusions

Among the group A subjects, 22.2% had past infection. The risk was higher in subjects older than 50 years, especially those born before 1960. Furthermore, current infection was found in 3.1% of the subjects and was correlated with increased gastric secretory ability.

Previous Helicobacter pylori infection-induced atrophic gastritis: A distinct disease entity in an understudied population without a history of eradication

Individuals with chronic atrophic gastritis who are negative for active H. pylori infection with no history of eradication therapy have been identified in clinical practice. By excluding false-negative and autoimmune gastritis cases, it can be surmised that most of these patients have experienced unintentional eradication of H. pylori after antibiotic treatment for other infectious disease, unreported successful eradication, or H. pylori that spontaneously disappeared. These patients are considered to have previous H. pylori infection-induced atrophic gastritis. In this work, we define these cases based on the following criteria: absence of previous H. pylori eradication; atrophic changes on endoscopy or histologic confirmation of glandular atrophy; negative for a current H. pylori infection diagnosed in the absence of proton-pump inhibitors or antibiotics; and absence of localized corpus atrophy, positivity for autoantibodies, or characteristic histologic findings suggestive of autoimmune gastritis. The risk of developing gastric cancer depends on the atrophic grade. The reported rate of developing gastric cancer is 0.31%-0.62% per year for successfully eradicated severely atrophic cases (pathophysiologically equal to unintentionally eradicated cases and unreported eradicated cases), and 0.53%-0.87% per year for spontaneously resolved cases due to severe atrophy. Therefore, for previous H. pylori infection-induced atrophic gastritis cases, we recommend endoscopic surveillance every 3 years for high-risk patients, including those with endoscopically severe atrophy or intestinal metaplasia. Because of the difficulty involved in the endoscopic diagnosis of gastric cancer in cases of previous infection, appropriate monitoring of the high-risk subgroup of this understudied population is especially important.

Diagnosis of Helicobacter pylori infection

The progress this year in Helicobacter pylori diagnosis concerned essentially endoscopy and molecular techniques. New endoscopy techniques such as blue laser imaging and magnifying narrow band imaging allow the visualization of mucosal aspects representing H. pylori infection, intestinal metaplasia, and even ambiguous early gastric cancer. Several real-time PCRs have also been used either to quantify H. pylori or to detect mutations associated with clarithromycin resistance in gastric biopsies or applied on gastric juice, stool specimens, or the oral cavity. The presence of H. pylori in free-living amebae purified from wastewater and drinking water was also determined by PCR and sequencing, as well as culture from a few wastewater samples. Among the noninvasive methods, the urea breath test was used in different conditions, including with a new test meal, which is claimed to avoid the proton-pump inhibitor washout period before testing. Several articles concerning antibody detection and stool antigen test were also published.