Breath Fingerprint of Colorectal Cancer Patients Based on the Gas Chromatography-Mass Spectrometry Analysis.

The human body emits a multitude of volatile organic compounds (VOCs) via tissues and various bodily fluids or exhaled breath. These compounds collectively create a distinctive chemical profile, which can potentially be employed to identify changes in human metabolism associated with colorectal cancer (CRC) and, consequently, facilitate the diagnosis of this disease. The main goal of this study was to investigate and characterize the VOCs' chemical patterns associated with the breath of CRC patients and controls and identify potential expiratory markers of this disease. For this purpose, gas chromatography-mass spectrometry was applied. Collectively, 1656 distinct compounds were identified in the breath samples provided by 152 subjects. Twenty-two statistically significant VOCs (p-xylene; hexanal; 2-methyl-1,3-dioxolane; 2,2,4-trimethyl-1,3-pentanediol diisobutyrate; hexadecane; nonane; ethylbenzene; cyclohexanone; diethyl phthalate; 6-methyl-5-hepten-2-one; tetrahydro-2H-pyran-2-one; 2-butanone; benzaldehyde; dodecanal; benzothiazole; tetradecane; 1-dodecanol; 1-benzene; 3-methylcyclopentyl acetate; 1-nonene; toluene) were observed at higher concentrations in the exhaled breath of the CRC group. The elevated levels of these VOCs in CRC patients' breath suggest the potential for these compounds to serve as biomarkers for CRC.

Age-Based Comparative Analysis of Colorectal Cancer Colonoscopy Screening Findings.

Background and Objectives: Colorectal cancer (CRC) incidence is rapidly emerging among individuals <50 years, termed as early-onset colorectal cancer (EOCRC). This study aimed to probe variations in tumorigenic pathology and relevant manifestations (polyp and adenoma incidence) between suspected cases of EOCRC and late-onset CRC (LOCRC; ≥50 years of age). Materials and Methods: Between September 2022 and February 2023, colonoscopy-based screening data from 1653 patients were included in this study. All eligible participants were divided into two groups, depending upon patient age, where Group 1 consisted of 1021 patients aged <50 years while Group 2 consisted of 632 patients aged ≥ 50 years. Polyp samples were collected when identified peri-procedurally and characterized according to World Health Organization criteria. Results: Polyp detection rate was 42% for the <50-year age group, while this was 76% for the ≥50-year age group. Additionally, the <50-year age group predominated in hyperplastic polyp manifestation, particularly within the rectum and sigmoid colon. In addition, the ≥50-year age group had increased prevalence of serrated polyps and differing adenoma manifestations. Conclusions: This investigation served to highlight the importance of age stratification for CRC colonoscopy-based screening effectiveness, with particular reference to evaluations that are based on polyp localization within differing colon regions.

Biopsy Sampling in Upper Gastrointestinal Endoscopy: A Survey from 10 Tertiary Referral Centres Across Europe.

BACKGROUND: Guidelines give robust recommendations on which biopsies should be taken when there is endoscopic suggestion of gastric inflammation. Adherence to these guidelines often seems arbitrary. This study aimed to give an overview on current practice in tertiary referral centres across Europe. METHODS: Data were collected at 10 tertiary referral centres. Demographic data, the indication for each procedure, endoscopic findings, and the number and sampling site of biopsies were recorded. Findings were compared between centres, and factors influencing the decision to take biopsies were explored. RESULTS: Biopsies were taken in 56.6% of 9,425 procedures, with significant variation between centres (p < 0.001). Gastric biopsies were taken in 43.8% of all procedures. Sampling location varied with the procedure indication (p < 0.001) without consistent pattern across the centres. Fewer biopsies were taken in centres which routinely applied the updated Sydney classification for gastritis assessment (46.0%), compared to centres where this was done only upon request (75.3%, p < 0.001). This was the same for centres stratifying patients according to the OLGA system (51.8 vs. 73.0%, p < 0.001). More biopsies were taken in centres following the MAPS guidelines on stomach surveillance (68.1 vs. 37.1%, p < 0.001). Biopsy sampling was more likely in younger patients in 8 centres (p < 0.05), but this was not true for the whole cohort (p = 0.537). The percentage of procedures with biopsies correlated directly with additional costs charged in case of biopsies (r = 0.709, p = 0.022). CONCLUSION: Adherence to guideline recommendations for biopsy sampling at gastroscopy was inconsistent across the participating centres. Our data suggest that centre-specific policies are applied instead.

Accuracy of two plasma antibody tests and faecal antigen test for non-invasive detection of H. pylori in middle-aged Caucasian general population sample.

OBJECTIVE: The aim of the study was to assess the accuracy of two plasma Helicobacter pylori (H. pylori) antibody test-systems and a stool antigen test (SAT) system in a general population sample in Latvia. MATERIALS AND METHODS: Blood and faecal samples were analysed in healthy individuals (40-64 years), referred for upper gastrointestinal endoscopy according to pilot study protocol within a population-based study investigating gastric cancer prevention strategies (GISTAR pilot study). Antibodies to H. pylori were assessed in plasma by latex-agglutination test and enzyme-linked immunosorbent assay (ELISA). H. pylori antigen in faecal samples was detected by a monoclonal enzyme immunoassay-based SAT. Histological assessment of H. pylori based on a modified Giemsa staining method was used as the gold standard. Individuals having received H. pylori eradication within one year prior to enrolment were excluded. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and overall accuracy were calculated. Receiver-operating characteristic curves were designed to estimate the optimal diagnostic cut-off value of tests. RESULTS: The analysis included 779 participants for latex-agglutination test, 1002 for ELISA and 672 individual samples for SAT. The sensitivity, specificity, PPV, NPV and overall accuracy were as follows: latex-agglutination test (86;81;87;80;84%), ELISA (97;72;83;94;86%) and SAT (87;81;87;81;85%), respectively. The optimal diagnostic cut-off value for ELISA test was ≥50.26 g/L. CONCLUSIONS: Although the performance of the three tests was comparable to each other, the three test systems showed suboptimal accuracy, with important implications for public health programs based on 'test-and-treat' strategy.

Detection of gastric atrophy by circulating pepsinogens: A comparison of three assays.

BACKGROUND: Circulating levels of pepsinogens have been used in high gastric cancer-risk Asian and European populations to triage endoscopic evaluation for more severe pathology. There are different analytic methods with uncertain correlations. We therefore compared diagnostic performance of three commonly used pepsinogen assays to detect histologically confirmed gastric atrophy. METHODS: We tested plasma samples from adult patients with (n=50) and without (n=755) moderate or severe gastric corpus atrophy, as determined histologically by consensus of three expert pathologists. A single laboratory measured pepsinogens I (PgI) and II (PgII) using commercially available assays: two ELISA assays produced by Biohit (Finland) and Vector Best (Russia), and a latex agglutination assay from Eiken (Japan). Quantitative correlations were assessed by Spearman statistics. Receiver operating characteristic (ROC) curves vs histological diagnosis were calculated using both the manufacturers' and optimized cutoffs. RESULTS: Pepsinogen levels were highly correlated among the assays (pairwise Rhos: PgI≥0.84, PgII≥0.87; all P-values<.01). Based on manufacturers' cutoffs, sensitivities, specificities and areas under the ROC curve for detecting moderate to severe histological corpus atrophy by PgI/PgII were 44%/91%/0.70, 56%/84%/0.76, and 52%/90%/0.77 for Biohit, Vector Best and Eiken, respectively. Cutoffs optimized by ROC or data mining analyses did not substantially improve test performance. CONCLUSIONS: Commercial assays for pepsinogen have good relative agreement but are imperfect tests for clinical diagnosis of gastric atrophy. IMPACT: Pepsinogen testing alone does not provide sufficient information for gastric cancer risk stratification. Future investigations should focus on other potential markers, in combination with pepsinogens.

Breath testing as potential colorectal cancer screening tool.

Although colorectal cancer (CRC) screening is included in organized programs of many countries worldwide, there is still a place for better screening tools. In this study, 418 breath samples were collected from 65 patients with CRC, 22 with advanced or nonadvanced adenomas, and 122 control cases. All patients, including the controls, had undergone colonoscopy. The samples were analysed with two different techniques. The first technique relied on gas chromatography coupled with mass spectrometry (GC-MS) for identification and quantification of volatile organic compounds (VOCs). The T-test was used to identify significant VOCs (p values < 0.017). The second technique relied on sensor analysis with a pattern recognition method for building a breath pattern to identify different groups. Blind analysis or leave-one-out cross validation was conducted for validation. The GC-MS analysis revealed four significant VOCs that identified the tested groups; these were acetone and ethyl acetate (higher in CRC), ethanol and 4-methyl octane (lower in CRC). The sensor-analysis distinguished CRC from the control group with 85% sensitivity, 94% specificity and 91% accuracy. The performance of the sensors in identifying the advanced adenoma group from the non-advanced adenomas was 88% sensitivity, 100% specificity, and 94% accuracy. The performance of the sensors in identifying the advanced adenoma group was distinguished from the control group was 100% sensitivity, 88% specificity, and 94% accuracy. For summary, volatile marker testing by using sensor analysis is a promising noninvasive approach for CRC screening.

Pepsinogen testing for evaluation of the success of Helicobacter pylori eradication at 4 weeks after completion of therapy.

BACKGROUND AND OBJECTIVE: Pepsinogen levels in plasma are increased by inflammation in the gastric mucosa, including inflammation resulting from Helicobacter pylori infection. A decrease in pepsinogen II level has been suggested as a reliable marker to confirm the successful eradication of infection. The aim of our study was to evaluate the potential role of pepsinogens I and II, gastrin-17 and H. pylori antibodies in confirming successful eradication. MATERIAL AND METHODS: Altogether 42 patients (25 women, 17 men), mean age 45 years (range 23-74), were enrolled. Pepsinogens I and II, gastrin-17 and H. pylori IgG antibodies were measured in plasma samples using an ELISA test (Biohit, Oyj., Finland) before the eradication and 4 weeks after completing the treatment. The success of eradication was determined by a urea breath test. RESULTS: Eradication was successful in 31 patients (74%) and unsuccessful in 11 patients (26%). Pepsinogen II decreased significantly in both the successful (P=0.029) and unsuccessful (P=0.042) eradication groups. Pepsinogen I decreased significantly in the successful (P=0.025) but not the unsuccessful (P=0.29) eradication group. The pepsinogen I/II ratio increased in the successful eradication group (P=0.0018) but not in the group in which treatment failed (P=0.12). There were no differences in gastrin-17 or H. pylori antibody values. CONCLUSIONS: A decrease in pepsinogen II levels cannot be used as a reliable marker for the successful eradication of H. pylori 4 weeks after the completion of treatment. The increase in pepsinogen I/II ratio reflects differences in pepsinogen production following the eradication irrespective of improvement in atrophy.

Autoimmune gastritis serological biomarkers in gastric cancer patients.

The role of autoimmunity in the pathogenesis of gastric cancer remains controversial. We studied antiparietal cell antibody (anti-PCA) and anti-intrinsic factor antibody (anti-IFA) levels and their associations with pepsinogen I/pepsinogen II levels in patients with gastric adenocarcinoma compared to a control group with mild or no atrophy of the stomach mucosa. Plasma levels of anti-PCA and anti-IFA were measured by ELISA (Inova Diagnostics Inc, San Diego, California, USA). The cutoff value for anti-PCA and anti-IFA positivity was ≥25 units. Altogether 214 patients (126 men, 88 women, median age 64.46, range: 35-86) with confirmed gastric adenocarcinoma and 214 control cases paired for age and sex were included in the study. Positive anti-PCA was present in 22 (10.3%) gastric cancer patients and controls (P ≥ 0.999); positive anti-IFA in 6 (2.8%) and 4 (1.9.%), P < 0.232, respectively. We did not find significant differences in anti-PCA and anti-IFA positivity between gastric cancer patients and the control group; further investigation is required to better understand the potential involvement of autoimmune gastritis in the development of gastric cancer.

Role of pre-existing incomplete intestinal metaplasia in gastric adenocarcinoma: A retrospective case series analysis.

BACKGROUND: Risk stratification for patients with gastric precancerous lesions for endoscopic surveillance remains controversial. AIM: To analysis of patients having developed gastric adenocarcinoma during the period of follow-up. METHODS: We conducted a retrospective study on patients having undergone upper endoscopy prior to the development of gastric adenocarcinoma. The presence and stage of precancerous lesions as well as subtype of intestinal metaplasia at the baseline endoscopy got evaluated. Literature mini-review was performed. RESULTS: Out of 1681 subjects in the Biobank, gastric adenocarcinoma was detected in five cases in whom previous endoscopy data with biopsies either from the corpus or antral part were available. All of the patients had incomplete intestinal metaplasia during the baseline endoscopy; all three subjects in whom intestinal metaplasia subtyping was performed according to Filipe et al, had Type III intestinal metaplasia. Two of the five cases had low Operative Link on Gastritis Assessment (OLGA) and Operative Link on Gastritis Intestinal Metaplasia Assessment (OLGIM) stages (I-II) at the baseline. CONCLUSION: The presence of incomplete intestinal metaplasia, in particular, that of Type III is a better predictor for gastric adenocarcinoma development than OLGA/OLGIM staging system. Subtyping of intestinal metaplasia have an important role in the risk stratification for surveillance decisions.

The Role of an Artificial Intelligence Method of Improving the Diagnosis of Neoplasms by Colonoscopy.

BACKGROUND: Colorectal cancer (CRC) is the third most common cancer worldwide. Colonoscopy is the gold standard examination that reduces the morbidity and mortality of CRC. Artificial intelligence (AI) could be useful in reducing the errors of the specialist and in drawing attention to the suspicious area. METHODS: A prospective single-center randomized controlled study was conducted in an outpatient endoscopy unit with the aim of evaluating the usefulness of AI-assisted colonoscopy in PDR and ADR during the day time. It is important to understand how already available CADe systems improve the detection of polyps and adenomas in order to make a decision about their routine use in practice. In the period from October 2021 to February 2022, 400 examinations (patients) were included in the study. One hundred and ninety-four patients were examined using the ENDO-AID CADe artificial intelligence device (study group), and 206 patients were examined without the artificial intelligence (control group). RESULTS: None of the analyzed indicators (PDR and ADR during morning and afternoon colonoscopies) showed differences between the study and control groups. There was an increase in PDR during afternoon colonoscopies, as well as ADR during morning and afternoon colonoscopies. CONCLUSIONS: Based on our results, the use of AI systems in colonoscopies is recommended, especially in circumstances of an increase of examinations. Additional studies with larger groups of patients at night are needed to confirm the already available data.

The Association of Circulating L-Carnitine, γ-Butyrobetaine and Trimethylamine N-Oxide Levels with Gastric Cancer.

Our study aimed to evaluate the association between gastric cancer (GC) and higher concentrations of the metabolites L-carnitine, γ-butyrobetaine (GBB) and gut microbiota-mediated trimethylamine N-oxide (TMAO) in the circulation. There is evidence suggesting that higher levels of TMAO and its precursors in blood can be indicative of either a higher risk of malignancy or indeed its presence; however, GC has not been studied in this regard until now. Our study included 83 controls without high-risk stomach lesions and 105 GC cases. Blood serum L-carnitine, GBB and TMAO levels were measured by ultra-high-performance liquid chromatography-mass spectrometry (UPLC/MS/MS). Although there were no significant differences between female control and GC groups, we found a significant difference in circulating levels of metabolites between the male control group and the male GC group, with median levels of L-carnitine reaching 30.22 (25.78-37.57) nmol/mL vs. 37.38 (32.73-42.61) nmol/mL (p < 0.001), GBB-0.79 (0.73-0.97) nmol/mL vs. 0.97 (0.78-1.16) nmol/mL (p < 0.05) and TMAO-2.49 (2.00-2.97) nmol/mL vs. 3.12 (2.08-5.83) nmol/mL (p < 0.05). Thus, our study demonstrated the association between higher blood levels of L-carnitine, GBB, TMAO and GC in males, but not in females. Furthermore, correlations of any two investigated metabolites were stronger in the GC groups of both genders in comparison to the control groups. Our findings reveal the potential role of L-carnitine, GBB and TMAO in GC and suggest metabolic differences between genders. In addition, the logistic regression analysis revealed that the only significant factor in terms of predicting whether the patient belonged to the control or to the GC group was the blood level of L-carnitine in males only. Hence, carnitine might be important as a biomarker or a risk factor for GC, especially in males.

The Detection of Colorectal Cancer through Machine Learning-Based Breath Sensor Analysis.

Colorectal cancer (CRC) is the third most common malignancy and the second most common cause of cancer-related deaths worldwide. While CRC screening is already part of organized programs in many countries, there remains a need for improved screening tools. In recent years, a potential approach for cancer diagnosis has emerged via the analysis of volatile organic compounds (VOCs) using sensor technologies. The main goal of this study was to demonstrate and evaluate the diagnostic potential of a table-top breath analyzer for detecting CRC. Breath sampling was conducted and CRC vs. non-cancer groups (105 patients with CRC, 186 non-cancer subjects) were included in analysis. The obtained data were analyzed using supervised machine learning methods (i.e., Random Forest, C4.5, Artificial Neural Network, and Naïve Bayes). Superior accuracy was achieved using Random Forest and Evolutionary Search for Features (79.3%, sensitivity 53.3%, specificity 93.0%, AUC ROC 0.734), and Artificial Neural Networks and Greedy Search for Features (78.2%, sensitivity 43.3%, specificity 96.5%, AUC ROC 0.735). Our results confirm the potential of the developed breath analyzer as a promising tool for identifying and categorizing CRC within a point-of-care clinical context. The combination of MOX sensors provided promising results in distinguishing healthy vs. diseased breath samples. Its capacity for rapid, non-invasive, and targeted CRC detection suggests encouraging prospects for future clinical screening applications.

Assessment of Serum Pepsinogens with and without Co-Testing with Gastrin-17 in Gastric Cancer Risk Assessment-Results from the GISTAR Pilot Study.

Introduction−−Serum pepsinogen tests for gastric cancer screening have been debated for decades. We assessed the performance of two pepsinogen assays with or without gastrin-17 for the detection of different precancerous lesions alone or as a composite endpoint in a Latvian cohort. Methods−−Within the intervention arm of the GISTAR population-based study, participants with abnormal pepsinogen values by ELISA or latex-agglutination tests, or abnormal gastrin-17 by ELISA and a subset of subjects with all normal biomarker values were referred for upper endoscopy with biopsies. Performance of biomarkers, corrected by verification bias, to detect five composite outcomes based on atrophy, intestinal metaplasia, dysplasia or cancer was explored. Results−−Data from 1045 subjects were analysed, of those 273 with normal biomarker results. Both pepsinogen assays showed high specificity (>93%) but poor sensitivity (range: 18.4−31.1%) that slightly improved when lesions were restricted to corpus location (40.5%) but decreased when dysplasia and prevalent cancer cases were included (23.8%). Adding gastrin-17 detection, sensitivity reached 33−45% while specificity decreased (range: 61.1−62%) and referral rate for upper endoscopy increased to 38.6%. Conclusions−−Low sensitivity of pepsinogen assays is a limiting factor for their use in population-based primary gastric cancer screening, however their high specificity could be useful for triage.

Modular Point-of-Care Breath Analyzer and Shape Taxonomy-Based Machine Learning for Gastric Cancer Detection.

BACKGROUND: Gastric cancer is one of the deadliest malignant diseases, and the non-invasive screening and diagnostics options for it are limited. In this article, we present a multi-modular device for breath analysis coupled with a machine learning approach for the detection of cancer-specific breath from the shapes of sensor response curves (taxonomies of clusters). METHODS: We analyzed the breaths of 54 gastric cancer patients and 85 control group participants. The analysis was carried out using a breath analyzer with gold nanoparticle and metal oxide sensors. The response of the sensors was analyzed on the basis of the curve shapes and other features commonly used for comparison. These features were then used to train machine learning models using Naïve Bayes classifiers, Support Vector Machines and Random Forests. RESULTS: The accuracy of the trained models reached 77.8% (sensitivity: up to 66.54%; specificity: up to 92.39%). The use of the proposed shape-based features improved the accuracy in most cases, especially the overall accuracy and sensitivity. CONCLUSIONS: The results show that this point-of-care breath analyzer and data analysis approach constitute a promising combination for the detection of gastric cancer-specific breath. The cluster taxonomy-based sensor reaction curve representation improved the results, and could be used in other similar applications.

Who Could Be Blamed in the Case of Discrepant Histology and Serology Results for Helicobacter pylori Detection?

BACKGROUND: Discrepancies between histology and serology results for Helicobacter pylori detection could be caused by a variety of factors, including a biopsy sampling error, expertise of the pathologist, natural loss of infection due to advanced atrophy, or a false-positive serology in the case of a previous infection, since antibodies may be present in blood following recovery from the infection. AIMS: To identify true H. pylori-positive individuals in discrepant cases by serology and histology using real time polymerase chain reaction (RT-PCR) as a gold standard. METHODS: Study subjects with discrepant histology and serology results were selected from the GISTAR pilot study data base in Latvia. Subjects having received previous H. pylori eradication therapy or reporting use of proton pump inhibitors, antibacterial medications, or bismuth containing drugs one month prior to upper endoscopy were excluded. We compared the discrepant cases to the corresponding results of RT-PCR performed on gastric biopsies. RESULTS: In total, 97 individuals with discrepant results were identified: 81 subjects were serology-positive/histology-negative, while 16 were serology-negative/histology-positive. Among the serology-positive/histology-negative cases, 64/81 (79.0%) were false-positives by serology and, for the majority, inflammation was absent in all biopsies, while, in the serology-negative/histology-positive group, only 6.2% were proven false-positives by histology. CONCLUSIONS: Among this high H. pylori prevalent, middle-aged population, the majority of discrepant cases between serology and histology were due to false positive-serology, rather than false-negative histology. This confirms the available evidence that the choice of treatment should not be based solely on the serological results, but also after excluding previous, self-reported eradication therapy.

The Diagnostic Value of Anti-Parietal Cell and Intrinsic Factor Antibodies, Pepsinogens, and Gastrin-17 in Corpus-Restricted Atrophic Gastritis.

We aimed to determine the diagnostic value of anti-parietal cell antibodies (anti-PCA), anti-intrinsic factor antibodies (anti-IFA), pepsinogen ratio (PGI/II), and gastrin-17 (G-17) in corpus-restricted atrophic gastritis (CRAG) detected by ELISA (Inova, Biohit). Our study compared 29 CRAG cases against 58 age- and sex-matched controls with mild or no atrophy. Anti-PCA and anti-IFA positive cutoff values were ≥25 units for both. PGI/II value <3 was considered characteristic for atrophy; positive cutoff values for G-17 and anti-H. pylori IgG were >5 pg/L and >30 EIU. Anti-PCA was positive in 65.5% For CRAG cases and 13.8% of the controls (p < 0.0001), anti-IFA was positive in 13.8% and 0% (p = 0.01), respectively. Decreased pepsinogen levels were present in 79.3% of CRAG cases and 10.3% of the controls (p < 0.0001). PGI/II ratio was the best single biomarker, with sensitivity = 79%, specificity = 90%, and AUC 0.90. The combined use of PGI/II and anti-PCA resulted in AUC 0.93 for detecting CRAG. Our study suggests that the best combination of non-invasive biomarkers for detecting CRAG is PGI/II with anti-PCA. The addition of G-17 and anti-IFA is of little utility in clinical application.

High-risk individuals for gastric cancer would be missed for surveillance without subtyping of intestinal metaplasia.

The use of Operative Link on Gastritis Assessment (OLGA) and Operative Link on Gastritis Assessment based on Intestinal Metaplasia (OLGIM) staging system is recommended for identifying subjects at risk for developing gastric cancer; usually high-risk lesions are considered only as stages III and IV. Accumulating evidence suggests that incomplete intestinal metaplasia (IM) is important in the development of gastric cancer. Our aim has been to identify the prevalence of incomplete IM in patients with low-risk OLGA/OLGIM stages among a high-risk general population. Healthy adult volunteers aged 40-64 years were invited to undergo upper endoscopy within a regional GISTAR pilot study in Kazakhstan (n = 166). Gastric lesions were staged according to OLGA/OLGIM staging system. High iron diamine-alcian blue (HID-AB) was used for subtyping IM. IM prevalence overall was 45.8%. Incomplete IM was present in 52.6% (type II in 30.3% and type III in 22.3%), whereas complete IM was found in 47.4% individuals. The prevalence of OLGIM I and II stage were 39.8 and 4.8%, respectively, whereas OLGIM III was observed in 1.2%. The prevalence of incomplete IM in patients stratified to OLGIM I was 54.5% (type II in 31.8% and type III in 22.7%). High prevalence of incomplete IM was detected not only in subjects with extensive IM, but in those stratified as at the OLGIM I stage. Without IM subtyping, patients with high risk of gastric cancer development would be missed for surveillance.

Low Prevalence of Celiac Disease among Patients with Functional Gastrointestinal Disorders in Latvia.

BACKGROUND AND AIMS: Studies suggest that the prevalence of celiac disease (CD) is increased in individuals with functional gastrointestinal disorders (FGIDs), in particular, irritable bowel syndrome (IBS); however, the evidence is conflicting. We aimed to analyze the prevalence of CD in patients with FGIDs in Latvia. METHODS: This retrospective study included patients with FGIDs, referred for a gastroenterologist consultation in a secondary gastroenterology practice unit. Patients were divided into three groups - patients only with IBS (IBS group), patients only with functional dyspepsia (FD) (FD group), patients with mixed symptoms IBS and FD (Mixed group). Patient levels of tissue transglutaminase IgA (tTG-IgA) and/or antiendomysial IgA group antibodies (EMA-IgA) were evaluated. Four duodenal biopsies were obtained and reported according to Marsh classification. Patients diagnosed or being referred for confirmation of CD were excluded from the study. RESULTS: Overall, 1,833 FGIDs patients were enrolled. Celiac serology was available for 1,570 patients, duodenal histology for 582 patients, both histology and serology for 319 patients. In total, celiac seropositivity was present in 1.78% (28/1570) (3.18% in IBS group, 0.90% in FD group and 1.11% of cases in the mixed group). Fifteen patients had histopathological changes (2.58%; 15/582). Three IBS patients (2.36%) were both serology and biopsy positive. None of the FD patients had CD. CONCLUSION: Prevalence of biopsy-proven CD in patients from Latvia with FGIDs was low. Routine screening for CD could be considered only among patients with IBS.

Pepsinogen test for the evaluation of precancerous changes in gastric mucosa: a population-based study.

AIMS: The aim of the study was to evaluate the rationale of blood pepsinogen (PG) testing in population based screening settings. METHODS: Participants from a cross-sectional population-based study of cardiovascular risk factors in Latvia were invited to participate in the current study. Pepsinogen I and II were measured in blood samples taken during the initial study and at follow-up; upper gastrointestinal endoscopy was performed. There were three groups of patients: with moderately decreased (PG I< 70 ng/ml and PG I/PG II ratio < 3), with strongly decreased (PG I< 30 ng/ml and PG I/PG II ratio < 2), and with normal PG level. Biopsy with H. pylori detection was performed (updated Sydney system). RESULTS: Results from 259 patients were analyzed. Pepsinogens were decreased in 133 (51.4%), H. pylori was positive in 177 (66.0%) cases. Mean age was significantly lower in patients with normal compared to strongly decreased PG level group (52.8 vs. 64.1 years, p<0.001). Prevalence of severe corpus atrophy was higher in the strongly decreased compared to the normal PG test group: 7.0% vs. 0%; the same tendency was noted in the distribution of OLGA stages III-IV - 10.5% and 0.0%, OLGIM stages III-IV - 3.5% and 0%, and low-grade dysplasia - 15.8% and 2.4% (p<0.05). Two cases of gastric cancer were found; both presented decreased PG levels. A strong association between H. pylori eradication and PG ratio dynamics was found (p<0.05). CONCLUSIONS: All high-risk lesions were found in the decreased PG test groups; two cancer cases were revealed. However, PG demonstrated low specificity and low value of repeated testing. The value of PG as a sole test for gastric cancer risk is limited.

Precancerous gastric conditions in high Helicobacter pylori prevalence areas: comparison between Eastern European (Lithuanian, Latvian) and Asian (Taiwanese) patients.

UNLABELLED: The aim of the study was to compare the prevalence and severity of precancerous condition--gastric atrophy and intestinal metaplasia (IM) between Eastern European (Lithuania and Latvia) and Asian (Taiwan) countries in population older than 55 years. METHODS: Patients aged 55 years and older, referred for upper endoscopy due to dyspeptic symptoms, were included in the study. Gastric biopsies were histological investigated according modified Sydney classification. Helicobacter pylori (H. pylori) was detected if any two of three methods (urease test, histology, and serology) were positive. RESULTS: Overall 322 patients included: 52 from Taiwan (TW), 171 from Latvia (LV) and 99 from Lithuania (LT). There were 227 (70%) females and 95 (30%) males. The mean age of TW patients was significantly lower (61.0+/-5.8 years), than of LV (68.1+/-7.3 years) and LT (66.5+/-7.5 years) patients. H. pylori was established in 224 (69.6%) patients. H. pylori positivity was established in 43 (82.7%) TW patients, in 112 (65.5%) LV patients, and in 69 (69.7%) LT patients (P>0.05). In H. pylori-infected patients, any atrophy either in the corpus or in the antrum of the stomach was detected in 26 (60.5%) TW patients, in 40 (35.7%) LV patients, and in 36 (52.2%) LT patients (between TW and LV patients P<0.005). Severe atrophy (grade 2 or 3) detected in 8 (18.6%) TW patients, in 17 (15.2%) LV patients, and in 18 (26.1%) LT patients (P>0.05). Intestinal metaplasia was detected in 22 (51.2%) TW patients, in 37 (33.0%) LV patients and in 31 (44.9%) LT patients among countries (P>0.05). There were no significant differences in proportions of different degrees of both atrophy and intestinal metaplasia among countries. Intestinal metaplasia was found in 79 (77.5%) of 102 patients with any degree of atrophy and in 11 (9.0%) of 122 patients without atrophy (P<0.0001). We found strong statistically significant correlations between atrophy and intestinal metaplasia in antrum (r=0.89), P<0.01, and corpus (r= 0.73), P<0.01. CONCLUSIONS: The prevalence of H. pylori in the elderly population is still high in LT, LV, and TW. There are no significant differences in prevalence of gastric atrophy and intestinal metaplasia among TW, LT, and LV. There is a strong correlation between gastric atrophy and intestinal metaplasia.