Helicobacter pylori and some aspects of gut microbiota in children.

Helicobacter pylori infection in children differs from infection in adults in many aspects. The rate of infection, epidemiology, clinical presentations and complications, the applicability of diagnostic tests, antibiotic resistance, treatment options, and success rates differ significantly. Due to all these differences, management guidelines for children and adults differ also substantially. In 2017, the Updated ESPGHAN and NASPGHAN Guidelines on the management of H. pylori infection in children were published, emphasizing the differences in clinical presentation and indications for treatment, stating that the primary goal of clinical investigation in children is to identify the cause of upper gastrointestinal symptoms rather than the presence of H. pylori infection. Therefore, the diagnosis should be based on upper endoscopy, and the "test and treat strategy" should not be used in children. Due to an increasing rate of antibiotic resistance worldwide, the updated guidelines recommend broader use of antimicrobial susceptibility testing for H. pylori strains in order to tailor eradication treatment accordingly. Moreover, treatment in children should be prescribed only when indicated and should be based on the rate of eradication in local populations aiming for treatment success above 90%. During the last two decades there has been a steady decrease in the rate of H. pylori infection in both children and adults in the Western world. Two recent publications studying the incidence of H. pylori infection confirmed that early childhood is a time for acquisition of infection both in industrialized and nonindustrialized countries. In addition, they showed that H. pylori could be acquired outside the family. In respect to the inverse association between H. pylori and allergy, a longitudinal study demonstrated that early exposure to H. pylori at any age was inversely associated with atopy and allergic conditions.

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.

Prevalence of Helicobacter pylori infection among preschool children in Latvia: no significant decrease in prevalence during a ten year period.

AIMS: Published data show a trend of decreasing prevalence of Helicobacter pylori in Eastern European countries due to socioeconomic changes. The aim of this study was to determine the prevalence of H. pylori infection among children in Latvia and to compare these results with previous studies in the same population. The risk factors associated with infection were also analysed. METHODS: Preschool children in kindergartens and primary health care centres were investigated using a stool antigen test. Their parents were asked to fill out a questionnaire about possible risk factors. Statistical analysis included Pearson's χ(2) test and linear regression analysis. RESULTS: The prevalence of H. pylori infection determined by the monoclonal stool antigen test in children aged 1-6 years (median 5 years) was 15.5% (15/101) (95% confidence interval 8.67-23.48%). In the regression analysis, H. pylori positivity was significantly negatively associated with the consumption of imported fruit at least once per week (p=0.02). CONCLUSIONS THE PREVALENCE OF H PYLORI IN THE STUDIED POPULATION HAS NOT DECREASED SIGNIFICANTLY DURING THE LAST DECADE AND IS STILL ASSOCIATED WITH SOCIOECONOMIC FACTORS THE ROLE OF SOME DIETARY FACTORS EG THE CONSUMPTION OF FRUIT IN THE SPREAD OF INFECTION SHOULD BE STUDIED FURTHER.

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.

Reply to Kocsmár, É.; Lotz, G. Comment on "Skrebinska et al. Who Could Be Blamed in the Case of Discrepant Histology and Serology Results for Helicobacter pylori Detection? Diagnostics 2022, 12, 133".

Dr. Kocsmár and Dr. Lotz have made important comments [...].

Randomised clinical trial: comparison of efficacy and adverse effects of a standard triple clarithromycin-containing regimen with high-dose amoxicillin and bismuth therapy in Helicobacter pylori eradication.

BACKGROUND: The clarithromycin-based triple therapy is the most prescribed Helicobacter pylori eradication regimen in Europe; it causes adverse effects in a significant proportion of subjects, leading to discontinuation. Alternative therapies are required because of increasing clarithromycin resistance or to decrease the adverse effects. AIMS: We compared the efficacy and spectrum of adverse effects of clarithromycin-based triple therapy with the high-dose amoxicillin/bismuth regimen. METHODS: A randomised clinical trial enrolled healthy individuals aged 40-64 years. H. pylori was assessed with a 13C-urea breath test. In total 579 H. pylori-positive subjects were randomly allocated in two groups: group 1: clarithromycin 500 mg, amoxicillin 1000 mg, esomeprazole 40 mg, all twice daily; group 2: bismuth subcitrate 240 mg twice daily, amoxicillin 1000 mg three times daily, esomeprazole 40 mg twice daily. Regimens were administered for 14 days.Information on treatment completion and adverse effects were collected via a telephone interview at 21-28 days after medication delivery. The efficacy was assessed by UBT 6 months after the treatment. RESULTS: We analysed 483 subjects for adverse effects (248 vs. 235 respectively). Furthermore, 316 subjects were analysed for efficacy. In per-protocol analysis, a higher efficacy was seen in group 1 (88.4 vs. 77.0%; P < 0.001); no difference was observed in compliance (90.3 and 91.2%). Therapy-related adverse effects were more common in group 1 (56.9 vs. 40.0%; P < 0.01). In intention-to-treat analysis no statistical difference in efficacy was revealed. CONCLUSIONS: Bismuth-based high-dose amoxicillin therapy showed a lower efficacy but was less frequently associated with adverse effects. Further research is required to examine the high-dose amoxicillin and bismuth-containing regimens in various populations to maximise eradication efficacy.

Factors Associated with False Negative Results in Serum Pepsinogen Testing for Precancerous Gastric Lesions in a European Population in the GISTAR Study.

The accuracy of plasma pepsinogen (Pg) as a marker for precancerous gastric lesions (PGL) has shown variable results. We aimed to identify factors associated with false negative (FN) cases in Pg testing and to adjust cut-off values for these factors in order to improve Pg yield. Plasma Pg was measured and upper endoscopy with biopsy was performed within the "Multicentric randomized study of Helicobacter pylori eradication and pepsinogen testing for prevention of gastric cancer mortality: the GISTAR study". A multivariable logistic model was built for FN and multiple factors. Values of Pg were compared and sensitivity and specificity were calculated using pre-existing Pg cut-offs for factors showing strong associations with FN. New cut-offs were calculated for factors that showed substantially lower sensitivity. Of 1210 participants, 364 (30.1%) had histologically confirmed PGL, of which 160 (44.0%) were FN. Current smokers, men, and H. pylori positives were more likely FN. Smoking in H. pylori negatives was associated with a higher Pg I/II ratio and substantially lower sensitivity of Pg testing than in other groups. Adjusting Pg cut-offs for current smokers by H. pylori presence improved sensitivity for detecting PGL in this group. Our study suggests that adjusting Pg cut-offs for current smokers by H. pylori status could improve Pg test performance.

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.

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.

Factors influencing participation in preventive interventions for gastric cancer: the results from the GISTAR study.

OBJECTIVES: Search-and-treat strategy for Helicobacter pylori and surveillance of patients with precancerous lesions are recommended to decrease the burden of gastric cancer in high-risk areas. We aimed to evaluate the acceptance of the target population to these strategies. METHODS: We applied a search-and-treat strategy combined with biomarker screening (pepsinogens I and II, gastrin-17) for atrophic gastritis to healthy individuals aged 40-64 years within the GISTAR Pilot study. Different means of invitation were evaluated - direct telephone calls, letters of invitation via the general practitioners. Participants with altered biomarker results were invited to undergo upper gastrointestinal endoscopy. H.pylori positive individuals were offered eradication therapy. Data on the compliance to the treatment and reasons for noncompliance were collected via telephone. RESULTS: Altogether 3453 participants were enrolled. The attendance of women participants was 1.9 times higher although active invitation strategies were mainly targeting men. The yield for the telephone invitations was higher than for mail-delivered invitations (2.1 calls vs. 7.7 letters required to recruit one study subject). Out of 661 individuals reached with the invitation to undergo upper endoscopy, 520 (78.7%) attended the procedure. Out of 1185 study subjects eligible for eradication, 810 (68.4%) accepted it. Of those having received the medication, 765(94.4%) completed it. The reasons for nonparticipation were the overall misconception of the importance of screening, busy schedule and others. CONCLUSIONS: While only the minority of the target population participated in the gastric cancer prevention strategy, relatively high compliance was seen among the participants. The acceptance rate and the identified reasons for refusing to participate in our study indicate that there is a need to raise gastric cancer awareness and its existent preventive strategies within the general population for their successful implementation in the community.

Prevalence and Potential Risk Factors of Helicobacter pylori Infection among Asymptomatic Individuals in Kazakhstan.

BACKGROUND: Helicobacter pylori (H. pylori) infection is associated with several risk factors such as demographic, socioeconomic status and personal habits, which vary in different populations. This is the most up-to-date data on H. pylori prevalence and potential risk factors for H. pylori infection among asymptomatic middle-aged individuals in Kazakhstan. METHODS: Apparently healthy individuals aged 40 to 64, who took part in the health control in the outpatient clinic, were invited to participate in the study; answered a questionnaire, donated a blood sample. The antibodies to H. pylori were analysed by latex agglutination method. The baseline characteristics of study subjects with or without H. pylori infection were compared using the Chi-square test. Odds ratio (OR) and 95% confidence intervals (CI) for the association between H. pylori infection and potential risk factors were estimated using multivariable logistic regression models. RESULTS: Altogether 166 subjects (59% male; the median age - 51 years old) were included; 104 (62.7%) were H. pylori positive. There were no statistically significant differences between H. pylori positive and H. pylori negative groups in respect to the gender, anthropometric measurements, socioeconomic factors and personal habits. The multiple variable analysis showed that age (OR, 1.99; 95% CI, 1.03 - 3.86; P=0.04) and increased salt intake (OR, 2.21; 95% CI, 1.12 - 4.35; P=0.02) were associated with H. pylori infection. CONCLUSIONS: More than half of the study subjects were infected with H. pylori in Kazakhstan. The prevalence of H. pylori infection was independently associated with older age and regular high salt consumption.

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.

Helicobacter pylori infection in children.

The review summarizes the articles published on Helicobacter pylori in children between April 2007 and March 2008. Evidence is emerging in different populations including developing countries that the prevalence of H. pylori is declining in all age groups. The reasons for this are unclear but it is unlikely that treatment of infection or improvement in socioeconomic conditions fully explains the decline. For the first time, differences in the inflammatory response between adults and children have been well characterized in a group of adults and children from Chile with similar levels of H. pylori infection. This study suggests that the reduced inflammatory response to H. pylori at a cellular level in children could be the consequence of an enhanced Treg cell response, which in turn down-regulates H. pylori-induced inflammation. The publication of the Paediatric European Register for Treatment of Helicobacter pylori study (PERTH) is important as it demonstrates the advantages of different centers working in collaboration for the benefit of children. It also highlights the fact that while bismuth-based treatment is more effective than proton pump inhibitor-based treatment in children, bismuth preparations are not widely available for use in children.

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.

Helicobacter pylori Infection and Risk Factors in Relation to Allergy in Children.

PURPOSE: To analyze presence of Helicobacter pylori infection and environmental risk factors among children with and without allergy. METHODS: Parents of children at primary health care centres/kindergartens and allergologist consultation were asked to answer a questionnaire and to bring a faecal sample. H. pylori infection was detected by monoclonal stool antigen test. Prevalence of H. pylori infection and risk factors were compared between individuals with and without allergy using χ2 test, ANOVA test and parameters and logistic regression. RESULTS: Among 220 children (mean age, 4.7 years; ±standard deviation 2.3 years) H. pylori positivity was non-significantly lower among patients with allergy (n=122) compared to individuals without allergy (n=98): 13.9% (17/122) vs. 22.4% (22/98); p=0.106. In logistic regression analysis presence of allergy was significantly associated with family history of allergy (odds ratio [OR], 8.038; 95% confidence interval [CI], 4.067-15.886; p<0.0001), delivery by Caesarean section (OR, 2.980; 95% CI, 1.300-6.831; p=0.009), exclusive breast feeding for five months (OR, 2.601; 95% CI, 1.316-5.142; p=0.006), antibacterial treatment during the previous year (OR, 2.381; 95% CI, 1.186-4.782; p=0.015). CONCLUSION: Prevalence of H. pylori infection did not differ significantly between children with and without allergy. Significant association of allergy with delivery by Caesarean section and antibacterial therapy possibly suggests the role of gastrointestinal flora in the development of allergy, while association with family history of allergy indicates the importance of genetic factors in the arise of allergy.

Multicentric randomised study of Helicobacter pylori eradication and pepsinogen testing for prevention of gastric cancer mortality: the GISTAR study.

INTRODUCTION: Population-based eradication of Helicobacter pylori has been suggested to be cost-effective and is recommended by international guidelines. However, the potential adverse effects of widespread antibiotic use that this would entail have not been sufficiently studied. An alternative way to decrease gastric cancer mortality is by non-invasive search for precancerous lesions, in particular gastric atrophy; pepsinogen tests are the best currently available alternative. The primary objective of GISTAR is to determine whether H pylori eradication combined with pepsinogen testing reduces mortality from gastric cancer among 40-64-year-old individuals. The secondary objectives include evaluation of H pylori eradication effectiveness in gastric cancer prevention in patients with precancerous lesions and evaluation of the potential adverse events, including effects on microbiome. METHODS AND ANALYSIS: Individuals are recruited from general population (50% men) in areas with high gastric cancer risk in Europe and undergo detailed lifestyle and medical history questionnaire before being randomly allocated to intervention or control groups. The intervention group undergoes H pylori testing and is offered eradication therapy if positive; in addition, pepsinogen levels are detected in plasma and those with decreased levels are referred for upper endoscopy. All participants are offered faecal occult blood testing as an incentive for study participation. Effectiveness of eradication and the spectrum of adverse events are evaluated in study subpopulations. A 35% difference in gastric cancer mortality between the groups is expected to be detectable at 90% power after 15 years if 30 000 individuals are recruited. Biological materials are biobanked for the main and ancillary studies. The study procedure and assumptions will be tested during the pilot phase. ETHICS AND DISSEMINATION: The study was approved by the respective ethics committees. An independent Data Safety and Monitoring Board has been established. The findings will be published in peer-reviewed journals and presented at scientific meetings. TRIAL REGISTRATION NUMBER: NCT02047994.

Helicobacter pylori and allergy: Update of research.

Recently a lot of literature has been published about the possible preventive action of Helicobacter pylori (H. pylori) against allergy. The present review summarizes research data about the association between H. pylori and allergic diseases, as well as discusses possible hypotheses about the preventive action of H. pylori against atopy. There is evidence from observational studies to support a weak inverse association between prevalence of H. pylori infection and allergy. However, confounders like some unidentified socioeconomic factors, antibiotic use and others could bias the association. Although data from cohort studies point to a possible association of H. pylori with some of the allergic diseases, no definite proof for causal relationship has been clearly demonstrated yet. A biological mechanism proposed to explain the preventive action of H. pylori to allergy is reduced exposure to a major stimulus for the generation of Treg cells in individuals without H. pylori infection. In addition, H. pylori could be an indicator for changes in gut microbiome, reflecting the complex interaction between microbes and immune system.

Long-term dynamics of gastric biomarkers after eradication of Helicobacter pylori infection.

BACKGROUND: Secretion of pepsinogen I (PgI), pepsinogen II (PgII), fasting gastrin-17 (fG-17) and stimulated gastrin-17 (sG-17) changes after Helicobacter pylori eradication. Few data are available on the long-term dynamics of gastric biomarkers after H. pylori eradication.The aim of this study was to investigate the dynamics of gastric biomarkers in H. pylori-positive patients after eradication over a 3-year period and to compare the levels with initially H. pylori-negative patients. MATERIALS AND METHODS: Blood samples for the detection of gastric biomarkers were obtained from dyspeptic patients coming for upper gastrointestinal endoscopy. In H. pylori-positive patients, after eradication therapy, three follow-up blood samples were drawn after 12, 24 and 36 months; in H. pylori-negative patients, two samples were taken - at 12 and after 30 months. Median values of biomarkers in follow-up samples were compared with the baseline sample. RESULTS: The final sample included 110 patients (median age 67 years, M/F ratio 27/83). In patients after H. pylori eradication (n=83) PgI, PgII, fG-17 and sG-17 had decreased significantly during a 36-month period, whereas the PgI/PgII ratio had increased significantly from 5.59 to 11.64. CONCLUSION: In H. pylori-positive dyspeptic patients, after eradication therapy, a decrease in PgI, PgII, fG-17 and sG-17 was observed after 36 months whereas an increase in the PgI/II ratio suggested an improvement in gastric atrophy. The median levels of gastric biomarkers in patients after H. pylori eradication therapy may become similar to biomarker levels among initially H. pylori-negative individuals.

Prevalence estimation of celiac disease in the general adult population of Latvia using serology and HLA genotyping.

BACKGROUND: Prevalence estimates for celiac disease (CD) depend on the method used. The role of deamidated gliadin peptide (DGP) and genetic testing in epidemiological studies and diagnostic settings of celiac disease (CD) has still to be established. OBJECTIVES: The objective of this article is to assess the prevalence of CD in Latvia by combining serological tests with DQ2.5/DQ8 testing. METHODS: A total of 1444 adults from a randomly selected cross-sectional general population sample were tested by ELISA for tTG IgA, DGP IgA and IgG antibodies (QUANTA Lite®, Inova Diagnostics Inc). Samples with tTG IgA ≥20U were tested for EMA IgA by indirect immunofluorescence assay, and all specimens with tTG IgA ≥15U were tested by QUANTA-Flash® chemiluminescent assays (CIA) (Inova Diagnostics Inc) for tTG IgA, DGP IgA and IgG. DQ2.5/8 was detected in individuals with any positive ELISA test and a subgroup of controls. RESULTS: Forty-three individuals (2.98%; 95% CI: 2.10-3.86%) tested positive by at least one ELISA test; 41.86% of the serology-positive individuals (any test above the cutoff) were DQ positive. Six individuals (0.42%; 95% CI: 0.09-0.75%) were triple ELISA positive, and DQ2.5 or DQ8 was positive in all; 0.35% (95% CI: 0.05-0.65%) were tTG IgA and EMA positive. Two tTG IgA-negative cases were both DGP IgG and IgA positive, both being DQ positive; including them in the "serology-positive" group would increase the prevalence to 0.49% (95% CI: 0.13-0.85%). CIA tests revealed 2 tTG IgA-positive and EMA-negative cases with a positive genotype. DQ2.5 or DQ8 genotype was positive in 28.6% of the serology-negative population. CONCLUSIONS: Estimates of the prevalence of CD in Latvia based on the serogenetic testing approach range from 0.35% to 0.49% depending on the criteria used. There is a rationale for combining serological tests and DQ2.5/8 genotyping.

Association of obesity with proteasomal gene polymorphisms in children.

The aim of this study was to ascertain possible associations between childhood obesity, its anthropometric and clinical parameters, and three loci of proteasomal genes rs2277460 (PSMA6 c.-110C>A), rs1048990 (PSMA6 c.-8C>G), and rs2348071 (PSMA3 c. 543+138G>A) implicated in obesity-related diseases. Obese subjects included 94 otherwise healthy children in Latvia. Loci were genotyped and then analyzed using polymerase chain reactions, with results compared to those of 191 nonobese controls. PSMA3 SNP frequency differences between obese children and controls, while not reaching significance, suggested a trend. These differences, however, proved highly significant (P < 0.002) in the subset of children reporting a family history of obesity. Among obese children denying such history, PSMA6 c.-8C>G SNP differences, while being nonsignificant, likewise suggested a trend in comparison to the nonobese controls. No PSMA6 c.-110C>A SNP differences were detected in the obese group or its subsets. Finally, PSMA3 SNP differences were significantly associated (P < 0.05) with circulating low-density lipoprotein cholesterol (LDL) levels. Our results clearly implicate the PSMA3 gene locus as an obesity risk factor in those Latvian children with a family history of obesity. While being speculative, the clinical results are suggestive of altered circulatory LDL levels playing a possible role in the etiology of obesity in the young.