Value of serum brain-derived neurotrophic factor and glial fibrillary acidic protein for detecting depression in patients with Helicobacter pylori infection

OBJECTIVE

Infection with helicobacter pylori (H. pylori) is associated with depression, and depression can affect the outcome of H. pylori treatment. This study aimed to evaluate the value of serum brain-derived neurotrophic factor (BDNF) and glial fibrillary acidic protein (GFAP) for predicting depression in H. pylori-positive patients.

METHOD

A total of 82H. pylori-positive and 82H. pylori-negative patients were recruited for this study. All patients underwent neuropsychological and gastrointestinal assessments and blood sampling. BDNF and GFAP levels were measured in serum. The least absolute shrinkage and selection operator (LASSO) model was used to determine a composite marker.

RESULTS

H. pylori-positive patients showed significantly increased serum GFAP levels and significantly decreased serum BDNF levels compared to H. pylori-negative patients. Among H. pylori-positive patients, serum levels of gastrin 17 (G-17), pepsinogen (PG) I/PGII, BDNF, and GFAP, as well as Gastrointestinal Symptom Rating Scale (GSRS) scores, were significantly correlated with Hamilton Depression Scale (HAMD-24) overall scores and factor scores. Interactions between serum BDNF/GFAP and gastrointestinal serum indices or GSRS scores were significantly associated with HAMD-24 scores in H. pylori-positive patients. The LASSO model indicated that the combination of serum BDNF, GFAP, and G-17 and GSRS scores could identify H. pylori-positive patients with depression with an area under the curve of 0.879.

CONCLUSION

Circulating changes in BDNF and GFAP were associated with the occurrence of depression in H. pylori-positive patients. A composite marker including neural and gastrointestinal function-related indices may be of value for identifying depression among H. pylori-positive patients.

A novel predictive formula for highly accurate discrimination between truly Helicobacter pylori-uninfected and currently infected/spontaneously eradicated individuals for gastric cancer screening

The ABC classification, which categorizes gastric cancer risk based on serum Helicobacter pylori (H pylori) antibody and pepsinogen levels, has a limitation of potentially misclassifying high-risk individuals as low risk. To overcome the problem, we previously developed a 4-parameter predictive formula (age, serum H pylori antibody, PGI, and PGII) using logistic regression analysis to accurately identify low-risk truly H pylori-uninfected status. Our predictive formula demonstrated superior sensitivity and specificity in distinguishing between low-risk truly uninfected individuals and high-risk currently/spontaneously eradicated status individuals, compared to the modified ABC classification based on latex immunoassay kits (traditional 3-parameter model). This study aimed to revalidate the diagnostic accuracy of the predictive formula in a new and different study population. We applied the predictive formula to the target population and compared the sensitivity and specificity with those of the traditional 3-parameter model. A total of 788 enrollees were analyzed: 703 were classified as truly uninfected, 45 as currently infected, and 40 as spontaneously eradicated according to the results of stool antigen testing and endoscopic findings. The sensitivities and specificities of the predictive formula and the traditional 3-parameter model were 89.5% and 87.1% versus 89.8% and 80.0%, respectively. The specificity of the predictive formula was superior in the 70 to 89 age range and H pylori antibody < 3 U/mL groups. The predictive formula had higher specificity than the traditional 3-parameter model. The results should contribute to efficient gastric cancer screening by predicting H pylori infection status.

Correlation of chronic atrophic gastritis with gastric-specific circulating biomarkers

BACKGROUND AND STUDY AIMS

It has been suggested that the combined detection of multiple serum biomarkers can effectively screen out the high-risk population of chronic atrophic gastritis in the general population. Therefore, it is necessary to establish an effective predictive model of chronic atrophic gastritis.

PATIENTS AND METHODS

Serum biopsies were assessed using five stomach-specific circulating biomarkers pepsinogen I (PGI), PGII, PGI/II ratio, anti- H. pylori antibody, and gastrin-17 (G-17) to identify high-risk individuals and evaluate the risk of developing chronic atrophic gastritis.

RESULTS

In the cross-sectional analysis, PGII, the PG ratio, G17, anti- H. pylori IgG were positively associated with the presence of chronic atrophic gastritis, and combined prediction of the five biomarkers was more accurate than single-factor prediction ((0.692 vs 0.54(PG1), 0.604 (PGⅡ), 0.616(PGI/II ratio), 0.629(G-17)).

CONCLUSION

The combination of PGI, PGII, the PGI/II ratio, G17, and anti-H. pylori antibodies for serological analysis are helpful to screen chronic atrophic gastritis high-risk subjects from the general population and recommend that these people carry out further endoscopy and biopsy.

B12 deficiency-related glossitis is highly associated with high gastrin-17 and low pepsinogen I

BACKGROUND

The causes of vitamin B12 (B12) deficiency are varied and mainly related to gastric disorders. Glossitis is a common oral manifestation of B12 deficiency and is often first seen by dentists. This study aimed to investigate the correlation between B12 deficiency-related glossitis (B12-def glossitis) and gastric serum biomarkers [gastrin-17(G17), pepsinogen I (PGI), pepsinogen II (PGII), and anti-Helicobacter pylori (H. pylori) antibodies], and preliminarily discuss the etiology of B12-def glossitis.

METHODS

A cross-sectional study was conducted in patients complaining of glossodynia, burning sensation, or severe recurrent oral ulcers, but patients with a history of gastrectomy were excluded. All subjects underwent a uniform oral examination and hematological tests.

RESULTS

Of 243 patients, 133 with B12-def glossitis were in the case group, and 110 with other oral mucosal diseases (non-glossitis) and normal B12 levels were in the control group. In the case group, 84.2% (112/133) showed high G17 and low PGI levels (G17hi PGIlow ). Univariate logistic regression showed that G17hi PGIlow was a high-risk factor for B12-def glossitis (OR: 92.44; 95% CI: 35.91, 238.02). Subgroup analyses in the case group showed that the G17hi PGIlow group presented with lower B12 levels and a lower positive rate of anti-H. pylori antibodies compared to the non-G17hi PGIlow group.

CONCLUSION

Gastric serum biomarkers in patients with B12-def glossitis generally showed G17hi PGIlow , suggesting possible atrophy of gastric corpus and fundus mucosa. The G17hi PGIlow and non-G17hi PGIlow groups may represent different etiologies of B12 deficiency.

Utilization of an Automated Latex Agglutination Turbidity Assay for Assessing Gastric Mucosal Alteration during Helicobacter pylori Infection

Background/Aims

: A latex agglutination turbidity (LA) assay to test for serum antibodies has been approved in Japan and Korea for mass screening of Helicobacter pylori infection. In this study, we evaluated the LA assay for diagnosing H. pylori infection and predicting gastric mucosal changes in a Mongolian population.

Methods

: In total, 484 individuals were classified into H. pylori-positive (n=356) and H. pylori-negative (n=128) groups, as determined by histology and H. pylori culture.

Results

: The best cutoff, sensitivity, and specificity values for the LA assay were 18.35 U/mL, 74.2%, and 65.6%, respectively. The LA values in the atrophic gastritis group were statistically higher than those in the other groups (healthy, chronic gastritis, intestinal metaplasia, and gastric cancer, p<0.0001). The cutoff value to distinguish the atrophic gastritis group from the other four groups was 32.0 U/mL, and its area under the curve was 0.673, which was the highest among the E-plate, pepsinogen (PG) I, PG II, and PG I/II ratio tests in our data. The odds ratios for atrophic gastritis determined by the LA assay and PG I test in multiple logistic regression were 2.5 and 1.9, respectively, which were significantly higher than for the other tests.

Conclusions

: The LA assay can determine the risk of atrophic gastritis, which in turn is a considerable risk factor for gastric cancer. We propose using this assay in combination with the PG I/II ratio to avoid missing gastric cancer patients who have a low LA value (less than 32.0 U/mL).

Comparison between the GastroPanel test and the serum pepsinogen assay interpreted with the ABC method-A prospective study

BACKGROUND AND AIMS

This study aimed to validate Helicobacter pylori serological and pepsinogen (PG) assays for detecting infection and gastric neoplasm.

METHODS

Individuals who underwent serum Chorus H. pylori and HBI PG assays were included from May to September 2023. The GastroPanel test was performed using the same blood sample. HBI assay findings were interpreted with the ABC method using the criteria of corpus atrophy (PG I ≤ 70 ng/mL & I/II ≤3) and advanced corpus atrophy (PG I ≤ 30 ng/mL & I/II ≤2).

RESULTS

A total of 144 H. pylori-infected and 184 non-infected Koreans were analyzed. The Chorus test (sensitivity 97.2%, specificity 89.1%) showed higher area under the curve (0.993 vs. 0.972, p = 0.003) than the GastroPanel test (sensitivity 95.8%, specificity 86.4%). Using the GastroSoft application, the incidence of gastric neoplasms was highest in the corpus atrophy group (50%), followed by the low acid-output (25.8%), H. pylori infection (11.6%), and antral atrophy (9.1%) groups. There were no gastric neoplasms in the normal and high acid output groups. Using the ABC method, the incidence of gastric neoplasms was highest in the corpus atrophy groups (23.8% in Groups C and D), followed by Group B (12.3%) and Group A (2.4%). Corpus atrophy interpreted with the GastroSoft showed poor agreement (k = 0.225) with corpus atrophy interpreted with the ABC method, whereas it showed excellent agreement (k = 0.854) with advanced corpus atrophy.

CONCLUSIONS

Although the Chorus test was more accurate than the GastroPanel test, both assays discriminated high-risk individuals by detecting atrophy or infection. There were no gastric neoplasms in the normal or high acid-output groups (GastroSoft application), and gastric neoplasm incidence was lowest in Group A (ABC method). Corpus atrophy determined by GastroSoft application is more consistent with advanced corpus atrophy determined by the ABC method than is corpus atrophy.

Randomized controlled trial comparing the costs of gastric cancer screening systems between serological risk-based upper gastrointestinal endoscopy and the existing barium photofluorography: gastric cancer screening labeled by serum examination in place of aged gastric cancer organized screening systems (GALAPAGOS study)

BACKGROUND

Although the risk of gastric cancer can be stratified according to Helicobacter pylori (H. pylori) IgG antibody titer and pepsinogen levels (ABC classification), a population-based gastric cancer screening system combining serological tests and endoscopy has not been introduced. This study aimed to compare the total testing cost per participant between the ABC classification method and the existing protocol.

METHODS

Using the minimization method with sex and age as allocation factors, 1206 participants were randomly assigned to the following two methods for a 5-year intervention: barium photofluorography as primary examination followed by detailed examination with upper gastrointestinal endoscopy (Ba-Endo) and risk-based upper gastrointestinal endoscopy by ABC classification (ABC-Endo). The primary endpoint was the total testing cost per participant over a 5-year period. The secondary endpoint was the expense required to detect one gastric cancer.

RESULTS

The total testing cost per participant was 39,711 yen in Ba-Endo (604 participants) and 45,227 yen in ABC-Endo (602 participants), with the latter being significantly higher (p < 0.001). During the intervention period, gastric cancer was found in 11 and eight participants in Ba-Endo and ABC-Endo, respectively. The expenses required to detect one gastric cancer were 2,240,931 yen in Ba-Endo and 3,486,662 yen in ABC-Endo.

CONCLUSIONS

The testing cost per participant turned out to be higher in the ABC-Endo group than in the Ba-Endo group. This superiority trial, based on the hypothesis that the cost of testing is lower for ABC-Endo than for Ba-Endo, was rejected.

Ultrasensitive fluorescence immunoassay of pepsinogen I based on enzyme-triggered decomposition of AuNCs/MnO2

Gastric cancer is a prevalent malignant tumor of the gastrointestinal tract accompanied by a high mortality rate; therefore, early gastric cancer screening is critical for improving patient survival. In this study, we present a facile fluorescence immunoassay for highly sensitive screening of pepsinogen I (PG I) based on a one-pot biomimetic mineralization process for the synthesis of gold nanocluster-anchored manganese dioxide (AuNCs/MnO2) nanosheets. MnO2 first quenches the fluorescence of AuNCs through the Förster resonance energy transfer effect, whereas the introduction of ascorbic acid (AA) leads to the decomposition of MnO2 and rapidly recovers the fluorescence of AuNCs. Based on the above principles and phenomena, we developed a sensitive fluorescence immunoassay for the in situ generation of AA to detect PG I. Specifically, in the presence of PG I, the sandwich-type immunoreactivity-enriched alkaline phosphatase-labeled secondary antibody catalyzes the production of AA from the substrate, which enhances the fluorescence intensity. Under optimized conditions, the fluorescence intensity increased linearly with the concentration of PG I (0.05 to 200 ng mL-1) with a limit of detection (LOD) of 0.013 ng mL-1 (S/N = 3). The designed sensing platform has good stability (more than one year) and excellent anti-interference capability and demonstrates satisfactory accuracy for detection in real samples compared to commercial ELISA kits.

Pepsinogen ratio and brachial-ankle pulse wave velocity: a cross-sectional study on their interrelationship in atherosclerosis

BACKGROUND

Existing research has established the pepsinogen ratio (PGR) as a complex biomarker, not only as an independent predictor for various gastrointestinal diseases but also in its association with atherosclerotic cardiovascular diseases. However, the precise mechanism linking changes in PGR to cardiovascular pathologies remains unclear. The objective of this study is to quantitatively elucidate the association between PGR and brachial-ankle pulse wave velocity (baPWV) as an indicator of atherosclerotic progression.

METHODS

We conducted a cross-sectional study that analyzed clinical data from 465 patients who underwent health screenings. One-way Analysis of Variance (ANOVA) identified potential risk factors affecting baPWV. Multiple logistic regression was employed to evaluate if PGR serves as an independent risk factor for elevated baPWV after accounting for these variables. Generalized additive models and smoothed curve fitting were utilized to investigate the possibility of a nonlinear association between PGR and baPWV. When such nonlinearity was found, threshold effect analysis pinpointed the inflection point in this relationship, followed by segmented correlation analyses.

RESULTS

PGR negatively correlated with both right baPWV (RbaPWV) and left baPWV (LbaPWV) after adjusting for confounders. Smoothed curve analyses revealed nonlinear relationships, with inflection points at 22.5 for RbaPWV and 22.3 for LbaPWV. For PGR values below 22.5, a significant negative correlation with RbaPWV was observed (β = - 6.3 cm/s, P < 0.001). Conversely, for PGR values above 22.5, no significant linear relationship was found (P = 0.141). Similarly, when PGR was below 22.3, a strong negative correlation with LbaPWV was detected (β = - 7.0 cm/s, P < 0.001), but such correlation was absent for higher PGR levels (P = 0.273).

CONCLUSION

The study reveals that PGR is associated with RbaPWV and LbaPWV in a nonlinear manner. Specifically, lower levels of PGR were linearly and inversely correlated with baPWV, but this relationship became nonlinear at higher PGR levels. These findings suggest that modulating PGR levels may offer a therapeutic strategy for managing atherosclerosis.

Sex-specific disparities of serum pepsinogen I in relation to body mass index

OBJECTIVES

The clinical significance of serum pepsinogen (PG) for screening gastric cancer has been a controversial topic. Serum PG I levels have been demonstrated to be correlated with age, sex, and the Helicobacter pylori (HP) infection. However, the underlying factors that influence serum PG I variations remain to be fully elucidated. We aimed to evaluate the impacts of sex and body mass index (BMI) on PG I in Chinese population.

METHODS

The cross-sectional study recruited 4,299 apparently healthy participants in Fujian Province. Serum PG levels were automatically measured using ELISA method. Serum H. pylori-IgG antibody was detected by the colloidal gold immunoassay. Clinical characteristics were obtained by questionnaire.

RESULTS

Totally, 2,263 participants who had tests of serum PG and anti-HP IgG antibody were enrolled. Increased BMI and serum uric acid were observed in males with low PG I value (<70 μg/L). Multiple logistic regression showed the presence of overweight was the independent risk factor for male participants with low PG I level (odds ratio [OR] 1.519; p=0.017). However, the association was not found in females.

CONCLUSIONS

Sex-specific association of serum low PG I with overweight was observed in the southeast coastal areas of China. Thus, effects of sexual dimorphism should not be ignored during the clinical utilization of serum PG I.

Identification of serologically active Helicobacter pylori antigens related to alterations in serum pepsinogen levels

Gastric adenocarcinoma is associated with Helicobacter pylori infection. The transition to a carcinogenic process is preceded by glandular atrophy and serum levels of pepsinogen I and II (PGI and PGII) correlate with this type of gastric lesions. Possible associations of serum PG levels in relation to the frequency of serological activity against H. pylori antigens were studied. Serum samples from patients with gastric pathology associated with H. pylori (n=26) and asymptomatic individuals as controls (n=37) were used. Seroactive antigens were identified by immunoblot using a protein extract of H. pylori. The antibody titers anti-H. pylori and the concentration of PGs in serum was determined by ELISA. Thirty-one seroactive antigens were identified, nine of which exhibited a differential frequency between both groups (116.7, 68.8, 61.9, 54.9, 45.6, 38.3, 36.5, 33.8 and 30.1kDa) and only 3 were related to altered levels of PGs in serum. In the control group, the seropositivity of the 33.8kDa antigen was related to an increase in PGII, while the 68.8kDa antigen was related to normal PG values (decreased PGII and elevated PGI/PGII levels) indicating that seropositivity to this antigen could be a protective factor to gastric pathology. The seropositivity of the 54.9kDa antigen was related to altered values of PGs indicative of inflammation and gastric atrophy (increased in PGII and decreased in PGI/PGII). The identification of serum alterations in pepsinogen levels related to seropositivity to H. pylori 33.8, 54.9 and 68.8kDa antigens sets a precedent for further study as possible prognostic serological biomarkers.

Serum pepsinogens can help to discriminate between H. pylori-induced and auto-immune atrophic gastritis: Results from a prospective multicenter study

BACKGROUND

Serum pepsinogen (PG) testing is recommended by the European guidelines for diagnosis of chronic atrophic gastritis (CAG). However, wide variations in diagnostic performances are observed, due to the differences in the extent of gastric atrophy, and possibly in its origin (Helicobacter pylori-, autoimmune (AIG)).

AIM

To analyze the diagnostic performances of PGs testing according to these different parameters, using enzyme-linked-immunosorbent serologic assay (ELISA) and chemiluminescent immunoassay (CLEIA).

METHODS

Serum samples from patients having undergone gastroscopy with biopsies in five French centers were collected prospectively. Sensitivity (Se), specificity (Sp), and Area Under Curve were analyzed according to the extent and origin of CAG.

RESULTS

Overall, 344 patients (156 males [45%]; mean age 58.8 [±14.2] years) were included, among whom 44 had AIG. Diagnostic performances of PG I for the detection of corpus CAG were excellent, with Se and Sp of 92.7% and 99.1% for ELISA and 90.5% and 98.2% for CLEIA, respectively. For AIG, corresponding values were 97.7% and 97.4% for ELISA, and 95.6% and 97.1% for CLEIA. In multivariate analysis, PG levels were associated with the auto-immune origin (p<0.001) but not with the extent of the atrophic gastritis.

CONCLUSIONS

Pepsinogens are highly efficient for the diagnosis of corpus-limited CAG and allow to discriminate AIG from H. pylori-induced gastritis.

Development and validation of LightGBM algorithm for optimizing of Helicobacter pylori antibody during the minimum living guarantee crowd based gastric cancer screening program in Taizhou, China

Gastric cancer continues to be a significant health concern in China, with a high incidence rate. To mitigate its impact, early detection and treatment is key. However, conducting large-scale endoscopic gastric cancer screening is not feasible in China. Instead, a more appropriate approach would be to initially screen high-risk groups and follow up with endoscopic testing as needed. We conducted a study on 25,622 asymptomatic participants aged 45-70 years from a free gastric cancer screening program in the Taizhou city government's Minimum Living Guarantee Crowd (MLGC) initiative. Participants completed questionnaires, blood tests, and underwent gastrin-17 (G-17), pepsinogen I and II (PGI and PGII), and H. pylori IgG antibody (IgG) assessments. Using the light gradient boosting machine (lightGBM) algorithm, we developed a predictive model for gastric cancer risk. In the full model, F1 score was 2.66%, precision was 1.36%, and recall was 58.14%. In the high-risk model, F1 score was 2.51%, precision was 1.27%, and recall was 94.55%. Excluding IgG, the F1 score was 2.73%, precision was 1.40%, and recall was 68.62%. We conclude that H. pylori IgG appears to be able to be excluded from the prediction model without significantly affecting its performance, which is important from a health economic point of view. It suggests that screening indicators can be optimized, and expenditures reduced. These findings can have important implications for policymakers, as we can focus resources on other important aspects of gastric cancer prevention and control.

Endoscopic evaluation by the Kyoto classification of gastritis combined with serum anti-Helicobacter pylori antibody testing reliably risk-stratifies subjects in a population-based gastric cancer screening program

BACKGROUND

We previously demonstrated that the Kyoto classification of gastritis was useful for judging the status of Helicobacter pylori infection in a population-based screening program, and that adding H. pylori antibody test improved its accuracy (UMIN000028629). Here, we tested whether our endoscopic diagnosis of H. pylori infection status reliably estimated gastric cancer risk in the program.

METHODS

Data were collected from1345 subjects who underwent endoscopic follow-up 4 years after the end of the registration. We analyzed the association of three diagnostic methods of H. pylori infection with gastric cancer detection: (1) endoscopic diagnosis based on the Kyoto classification of gastritis; (2) serum diagnosis according to the ABC method (H. pylori antibody and pepsinogen I and II); and (3) endoscopic diagnosis together with H. pylori antibody test.

RESULTS

During the follow-up, 19 cases of gastric cancer were detected. By Kaplan-Meier analysis, the detection rates of cancer were significantly higher in the past or current H. pylori infection groups than in the never-infected group with all 3 methods. By the Cox proportional hazards model, the hazard ratio for cancer detection was highest in evaluation with the combined endoscopic diagnosis and the antibody test (method 3; hazard ratio 22.6, 95% confidence interval 2.99-171) among the three methods (the endoscopic diagnosis (method 1); 11.3, 2.58-49.8, and the ABC method (method 2); 7.52, 2.49-22.7).

CONCLUSIONS

Endoscopic evaluation of H. pylori status with the Kyoto classification of gastritis, especially combined with serum anti-Helicobacter pylori antibody testing, reliably risk-stratified subjects in a population-based gastric cancer screening program.

Application of serum gastric function markers and digestive tumor indices to the diagnosis of early gastric cancer and precancerous lesions

OBJECTIVES

To study the levels of carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 199, CA724, CA242, pepsinogen (PG) I, PGII, gastrin-17 (G-17), the PGI/PGII ratio (PGR), as well as the expression of p27 and Ki67, in patients suffering from early gastric cancer and intraepithelial neoplasia and to provide new markers for the diagnosis of early gastric cancer and precancerous lesions.

METHODS

A retrospective study where the blood serum concentration of CEA, CA199, CA724, CA242, PGI, PGII, G-17 and PGR were tested and also the protein expression of p27 and Ki67 was detected in patients tissues by immunohistochemistry in the Gastrointestinal Endoscopy Center of the Affiliated Hospital of Xuzhou Medical University, Xuzhou, China, from March 2018 to March 2021.

RESULTS

Carbohydrate antigen 242 and CA199 levels in tumor tissue significantly differed among the groups. Pepsinogen I levels decreased with increasing disease severity, G-17 levels increased with the aggravation of severity, and p27 expression decreased with the severity.

CONCLUSION

The combination of serum gastric function markers (PGI and G-17) and p27 digestive tumor indices can serve as markers for the diagnosis of early gastric cancer and intraepithelial neoplasia.

Appropriateness of Proton Pump Inhibitor Prescription Evaluated by Using Serological Markers

Inappropriate prescription of proton pump inhibitors (PPI) has been widely reported, often lacking initial exclusion of Helicobacter pylori (HP) infection and evaluation of gastric functional status. The aim of this study was to evaluate the utility of gastric functional tests to define the acid output, as well as HP status, in order to better direct PPI therapy prescription. Dyspeptic patients without alarm symptoms from a primary care population were evaluated. For each patient, serum Pepsinogen I (PGI) and II (PGII), gastrin 17 (G17) and anti-HP IgG antibodies (Biohit, Oyj, Finland) were determined. For each subject, data were collected regarding symptoms, past medical history of HP infection, and PPI use. Therapeutic response to PPIs was determined according to PGI and G17 values, where G17 > 7 in the presence of elevated PGI and absence of chronic atrophic gastritis (CAG) was considered an adequate response. Among 2583 dyspeptic patients, 1015/2583 (39.3%) were on PPI therapy for at least 3 months before serum sampling, and were therefore included in the study. Active HP infection and CAG were diagnosed in 206 (20.2%) and 37 (3.6%) patients, respectively. Overall, an adequate therapeutic response to PPIs was observed in 34.9%, reaching 66.7% at the highest dose. However, 41.1% and 20.4% of patients showed low (G17 1-7) or absent (G17 < 1) response to PPI, regardless of the dosage used. According to gastric functional response, most patients currently on PPI maintenance therapy lack a proper indication for continuing this medication, either because acid output is absent (as in CAG) or because gastrin levels fail to rise, indicating absence of gastric acid negative feedback. Lastly, HP eradication is warranted in all patients, and gastric function testing ensures this pathogen is sought for and adequately treated prior to initiating long-term PPI therapy.

[Diagnostic Value of Serum Pepsinogen Ⅰ/Pepsinogen Ⅱ Combined with Tumor Markers for Helicobacter pylori-Positive Early-Stage Gastric Cancer]

Objective

To investigate the diagnostic value of serum pepsinogen (PG) Ⅰ/PGⅡ combined with tumor markers for Helicobacter pylori ( Hp)-positive early-stage gastric cancer.

Methods

A retrospective study was conducted with the clinical data of 109 patients with gastric cancer (the gastric cancer group), 115 patients with chronic atrophic gastritis (the benign group), 112 cases of low-grade intraepithelial neoplasia (the low grade group), 109 cases of high-grade intraepithelial neoplasia (the high grade group), and 104 healthy subjects who underwent the relevant screening tests as part of their general physical examination (the healthy group). All the subjects were admitted to or received care at our hospital between May 2018 and April 2021. The levels of serum PGⅠ, PGⅡ, carcinoembryonic antigen (CEA), carbohydrate antigen 199 (CA199), and carbohydrate antigen 724 (CA724), and Hp infection status were examined. The findings for these indicators were compared among the groups, and the differences in serum indicators in Hp-positive and Hp-negative patients were compared. The diagnostic value of serum PGⅠ/PGⅡ combined with tumor markers for Hp-positive early-stage gastric cancer was assessed with receiver operating characteristic (ROC) curve.

Results

The serum levels of PGⅠ and PGⅠ/PGⅡ decreased in successive order in the healthy group, the benign group, the low grade group, the high grade group, and the gastric cancer group ( P<0.05). The serum levels of PGⅡ, CEA, CA199, and CA724 in the gastric cancer group, the high grade group, and the low grade group were all higher than those in the healthy group and the benign group ( P<0.05). The Hp-positive rates of the gastric cancer group, the high grade group, the low grade group and the benign group were higher than that of the healthy group ( P<0.01). The levels of serum PGⅠ, PGⅡ, CEA, CA199, and CA724 of the Hp-positive subjects of the healthy group, the benign group, the low grade group, the high grade group, and the gastric cancer group were higher than those of the Hp-negative subjects ( P<0.05), while their PGⅠ/PGⅡ levels were always lower than those of the Hp-negative persons ( P<0.05). The specificity and area under the curve ( AUC) of serum PGⅠ/PGⅡ, CEA, CA199, and CA724 in the combined diagnosis of Hp-positive early-stage gastric cancer were higher than those of each indicator used alone in diagnosis ( P<0.05). In the gastric cancer group, the proportion of patients with PGⅠ/PGⅡ>2.32 was lower in the Hp-positive patients than that in the Hp-negative patients ( P<0.05), while the proportions of patients with CEA>66.99 ng/mL, CA199>110.35 U/mL, and CA724>44.20 U/mL were higher in the Hp-positive patients than those in the Hp-negative patients ( P<0.05).

Conclusion

Testing PGⅠ/PGⅡ in combination with CEA, CA199, and CA724 results in better diagnostic value for Hp-positive early-stage gastric cancer.

Collagenous gastritis in a young Chinese woman: A case report

BACKGROUND

Collagenous gastritis (CG) is a rare condition whose pathogenesis may be related to immune abnormalities. We report a case of CG from China.

CASE SUMMARY

A 24-year-old woman presented with recurrent abdominal distension and discomfort for 3 mo. Upper gastrointestinal endoscopy found diffuse nodular elevation-depression changes in the mucosa of the entire gastric corpus. Endoscopic ultrasound showed predominant involvement of the lamina propria and submucosa, and computed tomography imaging showed mild enhancement of the gastric wall. Pathological histology revealed that the thickness of the subepithelial collagen band was about 40 μm, and the Masson trichrome staining result was positive and the Congo red staining result was negative. This case is consistent with the child-adolescent type of CG.

CONCLUSION

Serum pepsinogen I, pepsinogen II, pepsinogen I/II ratio, and gastrin-17 may be potential non-invasive monitoring markers. Currently, treatments for CG vary, and the likely prognosis is unknown. Individual cases of gastric cancer in patients with CG have been reported.

Clinical characteristics and predictors of esophagogastric variceal bleeding among patients with HCV-induced liver cirrhosis: An observational comparative study

OBJECTIVES

To investigate the clinical characteristics, risk factors, and predictors of esophagogastric variceal bleeding in patients with hepatitis C virus (HCV)-induced liver cirrhosis.

METHODS

This comparative observational study was carried out on 100 patients suffering from post hepatitis cirrhosis and portal hypertension who were admitted to the Internal Medicine Department, Al-Azhar University Hospital, Damietta Egypt. Patients were classified into two groups: 50 of them presented with esophagogastric varices with acute variceal bleeding, and 50 patients presented without bleeding. Data were collected, coded, revised, and entered into the Stata software version 16.

RESULTS

The mean age of patients with bleeding was slightly higher than those without bleeding (55.58 ± 5.89 vs. 52.54 ± 9.01 years), p = 0.049. Mild ascites, positive H.Pylori, and Child-Pugh score B and C were an independent predictors of esophagogastric variceal bleeding (OR = 0.036, 95% CI: 0.0004-0.36; p = 0.005), (OR = 7.36, 95% CI: 1.44-37.59; p = 0.016), (OR = 19.0, 95% CI: 2.02-186.3; p = 0.010), and (OR = 40.51, 95% CI: 2.18-751.31; p = 0.013). The sensitivity of this model was 93.88%, specificity was 53.85%, PPV was 88.46%, NPV was 70.0%, correctly classified patients were 85.48%, and AUC was 90.27%. In the second model, pepsinogen level higher than 43.5 μg/l, AST (>54.5), Bilirubin (>1.45), and Hemoglobin (>11.5) were a significant independent predictors of esophagogastric variceal bleeding (OR = 1.18, 95% CI: 1.09-1.27; p<0.001), (OR = 1.14, 95% CI: 1.03-1.27; p = 0.007), (OR = 5.55, 95% CI: 1.21-25.43; p = 0.027), and (OR = 0.05, 95% CI: 0.008-0.32; p = 0.002), respectively. The sensitivity of this model was 92%, specificity was 98%, PPV was 97.87%, NPV was 92.45%, correctly classified patients were 95%, and AUC was 98.68%.

CONCLUSION

The independent predictors of esophagogastric variceal bleeding were ascites, positive H. pylori, Child-Pugh score B and C, pepsinogen level higher than 43.5 μg/l, AST (>54.5), bilirubin (>1.45), and hemoglobin (>11.5). Laboratory investigations are more reliable in predicting variceal bleeding and excluding non-variceal bleeding; however, clinical symptoms should not be neglected, especially H. pylori infection, ascites, and Child-Pugh score.

Correlation Analysis of Serum Pepsinogen, Interleukin, and TNF-α with Hp Infection in Patients with Gastric Cancer: A Randomized Parallel Controlled Clinical Study

Background

Gastric cancer pathological biopsy and visual examination have been the gold standard for gastric cancer diagnosis, but their operation is costly, demanding, and risky, so it is especially important to find an effective examination method in clinical practice.

Aims

To investigate the correlation between serum pepsinogen I (PGI), pepsinogen II (PGII), pepsinogen I and II ratio (PGR), IL-6, and TNF-α and Helicobacter pylori (Hp) infection in patients with gastric cancer.

Materials and Methods

Fifty patients with Hp-infected gastric cancer admitted to the Department of Gastroenterology of our hospital from January 2019 to December 2021 were selected for the study as the observation group, and another 50 patients without Hp-infected gastric cancer were selected as the comparison group to compare the correlation analysis of PGI, PGII, PGR, IL-6, and TNF-α with Hp infection between the two groups after admission and treatment.

Results

After measurement, PGI and PGII in the observation group were significantly lower than those in the comparison group, and TNF-α, IL-18, and IL-6 in the observation group were significantly higher than those in the comparison group, and the comparative differences were all statistically significant (P < 0.05). The results of multivariate logistic regression model analysis of independent risk factors for gastric cancer showed that IL-18, hs-CRP, and tumor necrosis factor- (TNF-) α were risk factors for Hp infection in gastric cancer.

Conclusion

The expression of IL-18, hs-CRP, and TNF-α factors in Hp-infected gastric cancer patients is correlated. IL-6, IL-18, and TNF-α are involved in the entire process from the onset to the development of Hp-positive gastric mucosal inflammation in patients, which is of great value in the diagnosis of gastric cancer and helps to assess the degree of progression and prognosis of gastric cancer.

Lifestyle and dietary factors associated with serologically detected gastric atrophy in a Caucasian population in the GISTAR study

OBJECTIVE

To identify dietary and lifestyle factors associated with decreased pepsinogen levels indicative of gastric atrophy.

METHODS

Participants aged 40 to 64 from the "Multicentric randomized study of H. pylori eradication and pepsinogen testing for prevention of gastric cancer mortality (GISTAR study)" in Latvia tested for serum pepsinogen, as well as for Helicobacter pylori infection by 13 C-urea breath test or serology were included. Data on sex, age, education, employment, diet, smoking, alcohol and proton pump inhibitor use were obtained by survey and compared for participants with and without serologically detected gastric atrophy defined as pepsinogen I/pepsinogen II ≤ 2 and pepsinogen I ≤ 30 ng/mL.

RESULTS

Of 3001 participants (median age 53, interquartile range, 11.0, 36.9% male) 52.8% had H. pylori and 7.7% had serologically detected gastric atrophy. In multivariate analysis, increasing age, consumption of alcohol, coffee, and onions were positively, while H. pylori , former smoking, pickled product and proton pump inhibitor use were inversely associated with gastric atrophy. Pepsinogen values were higher in smokers and those with H. pylori . Pepsinogen ratio was lower in those with H. pylori . When stratifying by H. pylori presence, significantly higher pepsinogen levels remained for smokers without H. pylori .

CONCLUSION

Several dietary factors and smoking were associated with serologically detected gastric atrophy. Pepsinogen levels differed by smoking and H. pylori status, which may affect the serologic detection of gastric atrophy. There seems to be a complicated interaction between multiple factors. A prospective study including atrophy determined by both serology and histology is necessary.

Association of serum pepsinogens and gastrin-17 with Helicobacter pylori infection assessed by urea breath test

Background

Association of gastric atrophy or cancer with levels of serum pepsinogens, gastrin-17 and anti-Helicobacter pylori IgG antibody have been extensively studied. However, the association of serum pepsinogen and gastrin-17 with H. pylori infection has not been studied in a large population.

Aim

To investigate the impact of H. pylori infection on serum levels of pepsinogens and gastrin-17.

Methods

A total of 354, 972 subjects who underwent health check-ups were included. Serum levels of pepsinogens and gastrin-17 were measured using the enzyme-linked immunosorbent assay. H. pylori infection was detected using ¹⁴C-urea breath test (UBT). Multivariable logistic regression analysis was used to investigate the association of serum pepsinogen and gastrin-17 with H. pylori infection.

Results

H. pylori prevalence was 33.18% in this study. The mean levels of pepsinogens and gastrin-17 were higher, while the mean pepsinogen-I/II ratio were lower among H. pylori-positive than -negative subjects. In H. pylori-positive subjects, pepsinogen and gastrin-17 levels correlated positively, whereas the pepsinogen-I/II ratio correlated negatively with UBT values (e.g., the mean serum level of pepsinogen-I in subjects with UBT values in the range of 100-499dpm, 500-1499dpm, and ≥1500dpm was 94.77 ± 38.99, 102.77 ± 43.59, and 111.53 ± 47.47 ng/mL, respectively). Compared with H. pylori-negative subjects, the adjusted odds ratio (aOR) of having pepsinogen-I ≤ 70 ng/mL in the three H. pylori-positive but with different UBT value groups was 0.31 (p<0.001), 0.16 (p<0.001), and 0.08 (p<0.001), respectively; while the aOR of having G-17>5.70 pmol/L was 4.56 (p<0.001), 7.43 (p<0.001), and 7.12 (p<0.001). This suggested that H. pylori-positive subjects with higher UBT values were less likely to have pepsinogen-I ≤70 ng/mL (a serum marker for gastric atrophy), but more likely to have gastrin-17 >5.70 pmol/L (a marker for peptic ulcer).

Conclusions

H. pylori-positive subjects with higher UBT values are unlikely to have gastric atrophy, but may have greater risk of severe gastritis or peptic ulcers. Our study suggests that H. pylori-positive patients with high UBT values may benefit the most from H. pylori eradication.

Family-based Helicobacter pylori infection status and transmission pattern in central China, and its clinical implications for related disease prevention

BACKGROUND

Helicobacter pylori (H. pylori) has characteristics of family cluster infection; however, its family-based infection status, related factors, and transmission pattern in central China, a high-risk area for H. pylori infection and gastric cancer, have not been evaluated. We investigated family-based H. pylori infection in healthy households to understand its infection status, related factors, and patterns of transmission for related disease prevention.

AIM

To investigate family-based H. pylori infection status, related factors, and patterns of transmission in healthy households for related disease prevention.

METHODS

Blood samples and survey questionnaires were collected from 282 families including 772 individuals. The recruited families were from 10 selected communities in the greater Zhengzhou area with different living standards, and the family members’ general data, H. pylori infection status, related factors, and transmission pattern were analyzed. H. pylori infection was confirmed primarily by serum H. pylori antibody arrays; if patients previously underwent H. pylori eradication therapy, an additional ¹³C-urea breath test was performed to obtain their current infection status. Serum gastrin and pepsinogens (PGs) were also analyzed.

RESULTS

Among the 772 individuals examined, H. pylori infection rate was 54.27%. These infected individuals were from 246 families, accounting for 87.23% of all 282 families examined, and 34.55% of these families were infected by the same strains. In 27.24% of infected families, all members were infected, and 68.66% of them were infected with type I strains. Among the 244 families that included both husband and wife, spouse co-infection rate was 34.84%, and in only 17.21% of these spouses, none were infected. The infection rate increased with duration of marriage, but annual household income, history of smoking, history of alcohol consumption, dining location, presence of gastrointestinal symptoms, and family history of gastric disease or GC did not affect infection rates; however, individuals who had a higher education level showed lower infection rates. The levels of gastrin-17, PGI, and PGII were significantly higher, and PGI/II ratio was significantly lower in H. pylori-infected groups than in H. pylori-negative groups.

CONCLUSION

In our study sample from the general public of central China, H. pylori infection rate was 54.27%, but in 87.23% of healthy households, there was at least 1 H. pylori-infected person; in 27.24% of these infected families, all members were infected. Type I H. pylori was the dominant strain in this area. Individuals with a higher education level showed significantly lower infection rates; no other variables affected infection rates.

Pepsinogens and Gastrin Demonstrate Low Discrimination for Gastric Precancerous Lesions in a Multi-Ethnic United States Cohort

Early identification of gastric precancerous lesions, including atrophic gastritis (AG) and intestinal metaplasia (IM), may improve gastric cancer detection and prevention. Because AG and IM are generally asymptomatic, many of the estimated 15 million Americans who carry these lesions remain undiagnosed.¹ AG and IM are associated with either active or prior Helicobacter pylori (Hp) infection. Hp infection leads to perturbations in the serum concentration of gastric hormones pepsinogen I (PGI), pepsinogen II, the pepsinogen I/II ratio (PGR), gastrin-17 (G-17), and Hp IgG.^2,3 In East Asia and other regions with high burden of Hp infection and gastric cancer, these biomarkers have been used as screening tools for AG and IM.⁴ However, there exists limited data on the sensitivity and discrimination of these serologic markers in low-Hp-prevalence populations, such as the United States.

Serum Pepsinogen and Gastrin Levels: Reliable Markers to Predict Small Intestinal Bacterial Overgrowth

BACKGROUND

Serum pepsinogen, a useful indicator of gastric acidity, could reflect small intestinal bacterial overgrowth. The aim of this study is to evaluate the relationship between small intestinal bacterial overgrowth and profiles including pepsinogen or gastrin.

METHODS

We conducted a prospective study with 62 patients with a functional gastrointestinal disorder. All patients underwent glucose breath test for small intestinal bacterial overgrowth, immediately followed by upper endoscopy to survey gastric injury and Campylobacter-like organism test for Helicobacter pylori and serum laboratory tests including gastrin, pepsinogen I and II.

RESULTS

The positivity to small intestinal bacterial overgrowth was 17.7%. Significantly, low total hydrogen concentration during a glucose breath test, low prevalence for gastric injury, and high H. pylori positivity rate were shown in groups with pepsinogen I/II ratio ≤ 3.5 compared to those with pepsinogen I/II ratio > 3.5 or in groups with serum gastrin > 35.4 pg/mL comparing to those with serum ≤ 35.4 pg/mL, respectively. A high gastrin level was independently associated with H. pylori infection. A proportionally correlated tendency between pepsinogen I/II ratio and total hydrogen concentration was shown, whereas that of inverse proportion between H2 and gastrin was observed. Old age was solely independent predicting factor for small intestinal bacterial overgrowth (P = .03) in the multivariate analysis.

CONCLUSION

Old age was significantly related to the presence of small intestinal bacterial overgrowth in functional gastrointestinal disorder patients. Although pepsinogen and small intestinal bacterial overgrowth seem irrelevant, elevated gastrin level may cautiously indicate a decreased breath hydrogen concentration. Further studies should consider the function of intestinal motility and gastric acidity in patients with hydrogen-producing small intestinal bacterial overgrowth.

Helicobacter pylori Infection and Serum Pepsinogen Level With the Risk of Gastric Precancerous Conditions: A Cross-sectional Study of High-risk Gastric Cancer Population in China

BACKGROUND AND AIM

Gastric precancerous conditions are generally considered to play an essential role in the gastric carcinogenesis cascade. This study identified risk factors of gastric precancerous conditions in a nationwide multicenter cross-sectional study.

METHODS

Individuals who made their visit to 115 hospitals in China for gastric cancer screening were recruited. Lifestyle habits and personal information were collected through a series of questionnaires. Serum biomarker test (pepsinogen I, pepsinogen II, gastrin-17, and anti-Helicobacter pylori immunoglobulin G antibody) and endoscopy were then performed. Risk factors for gastric precancerous conditions were identified by univariate and multivariate analyses.

RESULTS

Of 14,929 subjects eligible for analysis, 4477 (30.0%) developed gastric precancerous conditions and 405 (2.71%) developed gastric cancer. In multiple logistic regression, precancerous conditions were associated with advanced age [odds ratio (OR)=1.027; 95% confidence interval (Cl), 1.023-1.032; P<0.001], male gender (OR=1.303; 95% Cl, 1.188-1.429; P<0.001), H. pylori infection (OR=1.377; 95% Cl, 1.272-1.490, P<0.001), and smoking (OR=1.142; 95% Cl, 1.005-1.298, P=0.004), whereas they were inversely correlated with white meat intake (OR=0.731; 95% Cl, 0.673-0.794; P<0.001) and pepsinogen I level (30 to 70 subgroup OR=1.536; 95% Cl, 1.163-2.028; P=0.002; <30 subgroup OR=1.354; 95% Cl, 1.206-1.520; P<0.001). Also, the authors observed a statistically lower prevalence of reflux esophagitis (2.8% vs. 4.7%) and of gastric polyps (11.0% vs. 13.7%) in H. pylori-infected population.

CONCLUSIONS

Patients with H. pylori have a 1.4-fold higher risk of having gastric precancerous conditions. Besides, precancerous conditions were associated with advanced age, male gender, H. pylori infection, and smoking in a large population. However, regular white meat intake and higher pepsinogen I level were associated with reduced risk of having precancerous lesions.

Association Between Laryngopharyngeal Reflux and Media Otitis: A Systematic Review

OBJECTIVES

To investigate the relationship between laryngopharyngeal reflux (LPR) and recurrent (ROM) or chronic otitis media with effusion (COME).

DATABASES

PubMed, Scopus, and Cochrane Library.

METHODS

Three authors searched articles published between January 1980 and September 2020 about the association between LPR and the development of recurrent or chronic otitis media. Inclusion, exclusion, diagnostic criteria, and clinical outcome evaluation of included studies were analyzed using PRISMA criteria. The bias analysis of included studies was evaluated with the Tool to assess Risk of Bias of the CLARITY group.

RESULTS

Twenty-six clinical and three experimental articles met our inclusion criteria, accounting for 1,624 children and 144 adults with COME or ROM. According to the pH study type, the prevalence of LPR and gastroesophageal reflux disease (GERD) in OM patients were 28.7% (range, 8-100%) and 40.7 (range, 18-64%), respectively. The majority of studies identified pepsin or pepsinogen in middle ear effusion, with a range of mean concentrations depending on the technique used to measure pepsin. There was an important heterogeneity between studies regarding definition of COME, ROM, and LPR, exclusion criteria, methods used to measure pepsin/pepsinogen in middle ear secretions and outcome assessments.

CONCLUSION

The association between LPR and OM is still unclear. Future clinical and experimental studies are needed to investigate the association between LPR and OM in both children and adults through extensive gastric content analysis in middle ear suppurations and impedance-pH monitoring considering acid, weakly acid, and alkaline reflux events.

Significance of pepsinogen in screening for gastric intestinal metaplasia in Guangdong, China

OBJECTIVE

Diagnosis of gastric intestinal metaplasia (GIM) relies on gastroscopy and histopathologic biopsy, but their application in screening for GIM is limited. We aimed to identify serological biomarkers of GIM via screening in Guangdong, China.

METHODS

Cross-sectional field and questionnaire data, demographic information, past medical history, and other relevant data were collected. Blood samples were collected for pepsinogen (PG)I, PGII, gastrin-17, and Helicobacter pylori antibody testing, and gastroscopy and histopathologic biopsy were performed. Single factor and logistic regression analyses were used to evaluate the correlation between these indicators and GIM, and decision tree models were used to determine the cut-off points between indicators.

RESULTS

Of 443 participants enrolled, 87 (19.6%) were diagnosed with GIM. Single factor analysis showed that pepsin indicators (PGI, PGII, and PGI/PGII ratio) and the factors Mandarin as native language, urban residency, hyperlipidemia, and age were associated with GIM. Logistic regression analysis showed that PGI and age were associated with GIM.

CONCLUSIONS

Age is an important factor for predicting GIM progression; age >60 years increased its risk. Detection of GIM was higher in individuals with PGI levels >127.20 ng/mL, which could be used as a threshold indicating the need to perform gastroscopy and histopathologic biopsy.

Type I and type II Helicobacter pylori infection status and their impact on gastrin and pepsinogen level in a gastric cancer prevalent area

BACKGROUND

Type I Helicobacter pylori (H. pylori) infection causes severe gastric inflammation and is a predisposing factor for gastric carcinogenesis. However, its infection status in stepwise gastric disease progression in this gastric cancer prevalent area has not been evaluated; it is also not known its impact on commonly used epidemiological gastric cancer risk markers such as gastrin-17 (G-17) and pepsinogens (PGs) during clinical practice.

AIM

To explore the prevalence of type I and type II H. pylori infection status and their impact on G-17 and PG levels in clinical practice.

METHODS

Thirty-five hundred and seventy-two hospital admitted patients with upper gastrointestinal symptoms were examined, and 523 patients were enrolled in this study. H. pylori infection was confirmed by both ¹³C-urea breath test and serological assay. Patients were divided into non-atrophic gastritis (NAG), non-atrophic gastritis with erosion (NAGE), chronic atrophic gastritis (CAG), peptic ulcers (PU) and gastric cancer (GC) groups. Their serological G-17, PG I and PG II values and PG I/PG II ratio were also measured.

RESULTS

A total H. pylori infection rate of 3572 examined patients was 75.9%, the infection rate of 523 enrolled patients was 76.9%, among which type I H. pylori infection accounted for 72.4% (291/402) and type II was 27.6%; 88.4% of GC patients were H. pylori positive, and 84.2% of them were type I infection, only 11.6% of GC patients were H. pylori negative. Infection rates of type I H. pylori in NAG, NAGE, CAG, PU and GC groups were 67.9%, 62.7%, 79.7%, 77.6% and 84.2%, respectively. H. pylori infection resulted in significantly higher G-17 and PG II values and decreased PG I/PG II ratio. Both types of H. pylori induced higher G-17 level, but type I strain infection resulted in an increased PG II level and decreased PG I/PG II ratio in NAG, NAGE and CAG groups over uninfected controls. Overall PG I levels showed no difference among all disease groups and in the presence or absence of H. pylori; in stratified analysis, its level was increased in GC and PU patients in H. pylori and type I H. pylori-positive groups.

CONCLUSION

Type I H. pylori infection is the major form of infection in this geographic region, and a very low percentage (11.6%) of GC patients are not infected by H. pylori. Both types of H. pylori induce an increase in G-17 level, while type I H. pylori is the major strain that affects PG I and PG IIs level and PG I/PG II ratio in stepwise chronic gastric disease. The data provide insights into H. pylori infection status and indicate the necessity and urgency for bacteria eradication and disease prevention in clinical practice.

Characteristics of Helicobacter pylori-seropositive subjects according to the stool antigen test findings: a prospective study

BACKGROUND/AIMS

In countries with a higher risk of gastric atrophic gastritis, noninvasive tests are helpful for a more reliable diagnosis of Helicobacter pylori infection. The aim of this study was to evaluate the characteristics of seropositive subjects according to their stool H. pylori antigen test, serum pepsinogen (PG) assay, and endoscopic findings.

METHODS

Consecutive subjects who visited Konkuk University Medical Center for upper gastrointestinal endoscopy for a regular check-up were included in a prospective setting if the serum anti-H. pylori immunoglobulin G assay was positive. A H. pylori antigen stool test was measured using a stool H. pylori antigen enzyme-linked immunosorbent assay kit on the same day as a serum PG assay and endoscopy.

RESULTS

Of 318 seropositive subjects, 256 (80.5%) showed positive stool test findings. Subjects with a negative stool test result showed lower serum PG I (p < 0.001) and PG II (p < 0.001) levels and higher PG I/II ratio (p < 0.001) than those with a positive stool test. Chronic atrophic gastritis was more common in the positive stool test group than the negative stool test group on endoscopic finding (p = 0.009). A higher serum PG I level (p = 0.001) and a lower serum PG I/II ratio (p = 0.001) were independent risk factors for the presence of H. pylori antigen in stool.

CONCLUSION

A high serum PG level denotes an ongoing current H. pylori infection with positive stool H. pylori antigen test findings. Seropositive subjects with increased gastric secreting ability tend to have H. pylori in their fecal material as reflected by a positive stool H. pylori antigen test finding.

Immunochemical studies on the components of the pepsinogen system

Rabbit antisera to pepsin and pepsinogen were characterized by several immunological criteria. Both antisera inhibited the rennet activity of pepsin. Antipepsinogen protected pepsin from alkaline denaturation. Using antipepsinogen, precipitin analysis at pH 5.5 indicated that the native enzyme resembles the precursor more closely than did the denatured enzyme. However, all three proteins have some antigenic sites in common. Both antisera reacted more efficiently with their homologous antigens. When measured by C' fixation, the pepsinogen-antipepsinogen system was inhibited by pepsin and to a greater degree, by the activation mixture and the pepsin-inhibitor complex. Pepsin-antipepsin was inhibited by pepsinogen. The specificity of these two antibodies toward pepsin and pepsinogen conformation was used to measure the disappearance of pepsinogen and the concomitant appearance of pepsin during autocatalytic conversion at pH 4.6. The experimental results obtained during the conversion could be duplicated by using varying proportions of pepsin and pepsinogen in the model system. The potentialities of employing these antisera to detect conformational changes such as the unmasking of the pepsin moiety in pepsinogen molecules modified by physical or chemical reagents are discussed.

Antimicrobial peptides derived from pepsinogens in the stomach of the bullfrog, Rana catesbeiana

Three antimicrobial peptides, which had strong antimicrobial activity against a broad spectrum of microorganisms, were isolated from the stomach of the bullfrog, Rana catesbeiana. Two of the antimicrobial peptides were found to be derived from the N-terminal sequences of pepsinogen A and C prosequences. The amino acid sequences of the new antimicrobial peptides, named bullfrog pepsinogen A-derived antimicrobial peptide (bPaAP) and bullfrog pepsinogen C-derived antimicrobial peptide (bPcAP), were Gly-Val-Val-Lys-Val-Ser-Arg-Leu-Lys-Gly-Glu-Ser-Leu-Arg-Ala-Arg-Leu (MW 1865.5) and Ile-Ile-Lys-Val-Pro-Leu-Lys-Lys-Phe-Lys-Ser-Met-Arg-Glu-Val-Met-Arg-A sp-His-Gly-Ile-Lys-Ala-Pro-Val-Val-Asp-Pro-Ala-Thr-Lys-Tyr (MW 3691.6), respectively. The bPaAP and bPcAP adopted 35% and 42% amphipathic alpha-helical structure in 50% trifluoroethanol, respectively, and were non-hemolytic up to a concentration of 200 microg/ml. Synthesized pepsinogen C prosequences of monkey and human, which had similar structural characteristics as bPaAP and bPcAP, also showed antimicrobial activity at concentrations of 10-200 microg/ml. The third peptide was buforin I, previously found in the stomach of the Asian toad, Bufo bufo gargarizans. These findings strongly suggest that peptides derived from the prosequences of pepsinogens, along with buforin I, may contribute to the antimicrobial function of the gastrointestinal mucosa of vertebrates, including human.

Genetic polymorphisms detectable in human urine: their application to forensic individualization

This review describes several types of genetic polymorphism, which have recently been identified in human urine in our laboratory, and have also been found in other human body fluids such as blood, saliva and semen. These include uropepsinogen, ribonuclease, deoxyribonuclease I (DNase I), deoxyribonuclease II (DNase II), 43-kDa glycoprotein, alpha-L-fucosidase, glutamate pyruvate transaminase, alpha-2-HS-glycoprotein, transferrin and vitamin D-binding protein. Several substances can be detected more easily in urine than in plasma. The concentrations of uropepsinogen, DNase I and DNase II in blood plasma are too low for analysis, whereas those in urine are high enough for easy typing. In practice, DNase I-polymorphism is one of the most useful genetic markers for practical purposes, because of its higher content in various body fluids including urine, a well-balanced gene frequency, and its easy and accurate detectability. Furthermore, several genetic markers previously identified in blood and/or other forensic samples can be phenotyped reproducibly and easily from the corresponding urine samples. Thus, urine, in addition to the convenience and non-invasive nature of its collection, is by no means inferior to blood as a sample source for typing in the field of forensic science. Biochemical and serological typing of genetic polymorphisms present in human urine could offer useful information to practising forensic biologists for forensic individualization of urine samples.