Economic impact of inflammatory bowel disease in Catalonia: a population-based analysis.

Background: Inflammatory bowel disease (IBD) has a major economic impact on healthcare costs. Objectives: The aim of this study was to evaluate the current healthcare expenditure associated with IBD in a population-wide study in Catalonia. Design: Retrospective observational study. Methods: All patients with IBD included in the Catalan Health Surveillance System (CHSS) were considered eligible. The CHSS compiles data on more than 7 million individuals in 2020 (34,823 with IBD). Data on the use of healthcare resources and its economic impact were extracted applying the International Classification of Diseases, 10th revision, Clinical Modification codes (ICD-10-CM codes). Health expenditure, comorbidities, and hospitalization were calculated according to the standard costs of each service provided by the Department of Health of the Catalan government. The data on the IBD population were compared with non-IBD population adjusted for age, sex, and income level. IBD costs were recorded separately for Crohn's disease (CD) and ulcerative colitis (UC). Results: Prevalence of comorbidities was higher in patients with IBD than in those without. The risk of hospitalization was twice as high in the IBD population. The overall healthcare expenditure on IBD patients amounted to 164M€. The pharmacy cost represents the 60%. The average annual per capita expenditure on IBD patients was more than 3.4-fold higher (IBD 4200€, non-IBD 1200€). Average costs of UC were 3400€ and 5700€ for CD. Conclusion: The risk of comorbidities was twice as high in patients with IBD and their use of healthcare resources was also higher than that of their non-IBD counterparts. Per capita healthcare expenditure was approximately 3.4 times higher in the population with IBD. Trial registration: The study was not previously registered.

Economic impact of inflammatory bowel disease in Catalonia The manuscript includes data of the most recent epidemiologic data about the high economic impact of IBD in Catalonia.

Incidence of Myelotoxicity and Other Adverse Effects Related to Thiopurine Starting in Patients with Inflammatory Bowel Disease: Retrospective Observational Study in a Third-Level Hospital.

BACKGROUND AND OBJECTIVES: Thiopurines are an effective treatment for the maintenance of remission in inflammatory bowel disease (IBD). They can present adverse effects (AEs), with myelotoxicity being the most relevant. This study aims to determine the incidence of AEs related to the starting of thiopurines in our centre. METHODOLOGY: Retrospective study. The AEs in patients that were started on thiopurines between January 2016 and June 2020 were registered, with a two-year follow-up. The mean and standard deviation were used to describe the quantitative variables, and percentages and confidence intervals were used for the qualitative variables. The statistical significance was set at a p-value < 0.05. RESULTS: 98 patients were included, with 64 AEs detected in 48 patients (49%). Most of the AEs appeared in the first 6 months. The most relevant were: 21 neutropenia (21.4%), 19 hypertransaminasemia (19.4%), 13 digestive intolerances (13.2%), 6 acute pancreatitis (6.12%), 3 phototoxicity (3%), and 2 unknown origin fevers (2%). In 29 patients (29.4%) the treatment had to be suspended due to AEs. In 11 cases (11.2%), azathioprine (AZA) was switched to 6-mercaptopurine (6 MP) as 5 showed tolerance and 6 patients needed suspension due to AEs. Eight patients required hospital admission, but none of them needed intensive care unit admission. There were no fatal adverse effects. CONCLUSIONS: Thiopurines are a safe drug with few AEs, especially after the first months of treatment. These results suggest that periodic analytic follow-up may not be necessary after the initial period of treatment.

Coding and non-coding co-expression network analysis identifies key modules and driver genes associated with precursor lesions of gastric cancer.

BACKGROUND: Helicobacter pylori infection is the most important risk factor for gastric cancer (GC). Human gastric adenocarcinoma develops after long-term H. pylori infection via the Correa cascade. This carcinogenic pathway describes the progression from gastritis to atrophy, intestinal metaplasia (IM), dysplasia and GC. Patients with atrophy and intestinal metaplasia are considered to have precancerous lesions of GC (PLGC). H. pylori eradication and endoscopy surveillance are currently the only interventions for preventing GC. Better knowledge of the biology of human PLGC may help find stratification markers and contribute to better understanding of biological mechanisms. One way to achieve this is by using co-expression network analysis. Weighted gene co-expression network analysis (WGCNA) is often used to identify modules from co-expression networks and relate them to clinical traits. It also allows identification of driver genes that may be critical for PLGC. AIM: The purpose of this study was to identify co-expression modules and differential gene expression in dyspeptic patients at different stages of the Correa pathway. METHODS: We studied 96 gastric biopsies from 78 patients that were clinically classified as: non-active (n = 10) and chronic-active gastritis (n = 20), atrophy (n = 12), and IM (n = 36). Gene expression of coding RNAs was determined by microarrays and non-coding RNAs by RNA-seq. The WGCNA package was used for network construction, module detection, module preservation and hub and driver gene selection. RESULTS: WGCNA identified 20 modules for coding RNAs and 4 for each miRNA and small RNA class. Modules were associated with antrum and corpus gastric locations, chronic gastritis and IM. Notably, coding RNA modules correlated with the Correa cascade. One was associated with the presence of H. pylori. In three modules, the module eigengene (ME) gradually increased in the stages toward IM, while in three others the inverse relationship was found. One miRNA module was negatively correlated to IM and was used for a mRNA-miRNA integration analysis. WGCNA also uncovered driver genes. Driver genes show both high connectivity within a module and are significantly associated with clinical traits. Some of those genes have been previously involved in H. pylori carcinogenesis, but others are new. Lastly, using similar external transcriptomic data, we confirmed that the discovered mRNA modules were highly preserved. CONCLUSION: Our analysis captured co-expression modules that provide valuable information to understand the pathogenesis of the progression of PLGC.

Follow-Up Study Confirms the Presence of Gastric Cancer DNA Methylation Hallmarks in High-Risk Precursor Lesions.

To adopt prevention strategies in gastric cancer, it is imperative to develop robust biomarkers with acceptable costs and feasibility in clinical practice to stratified populations according to risk scores. With this aim, we applied an unbiased genome-wide CpG methylation approach to a discovery cohort composed of gastric cancer (n = 24), and non-malignant precursor lesions (n = 64). Then, candidate-methylation approaches were performed in a validation cohort of precursor lesions obtained from an observational longitudinal study (n = 264), with a 12-year follow-up to identify repression or progression cases. H. pylori stratification and histology were considered to determine their influence on the methylation dynamics. As a result, we ascertained that intestinal metaplasia partially recapitulates patterns of aberrant methylation of intestinal type of gastric cancer, independently of the H. pylori status. Two epigenetically regulated genes in cancer, RPRM and ZNF793, consistently showed increased methylation in intestinal metaplasia with respect to earlier precursor lesions. In summary, our result supports the need to investigate the practical utilities of the quantification of DNA methylation in candidate genes as a marker for disease progression. In addition, the H. pylori-dependent methylation in intestinal metaplasia suggests that pharmacological treatments aimed at H. pylori eradication in the late stages of precursor lesions do not prevent epigenome reprogramming toward a cancer signature.

Whole-Genome Sequencing and Comparative Genomics of Three Helicobacter pylori Strains Isolated from the Stomach of a Patient with Adenocarcinoma.

Helicobacter pylori is a common pathogen associated with several severe digestive diseases. Although multiple virulence factors have been described, it is still unclear the role of virulence factors on H. pylori pathogenesis and disease progression. Whole genome sequencing could help to find genetic markers of virulence strains. In this work, we analyzed three complete genomes from isolates obtained at the same point in time from a stomach of a patient with adenocarcinoma, using multiple available bioinformatics tools. The genome analysis of the strains B508A-S1, B508A-T2A and B508A-T4 revealed that they were cagA, babA and sabB/hopO negative. The differences among the three genomes were mainly related to outer membrane proteins, methylases, restriction modification systems and flagellar biosynthesis proteins. The strain B508A-T2A was the only one presenting the genotype vacA s1, and had the most distinct genome as it exhibited fewer shared genes, higher number of unique genes, and more polymorphisms were found in this genome. With all the accumulated information, no significant differences were found among the isolates regarding virulence and origin of the isolates. Nevertheless, some B508A-T2A genome characteristics could be linked to the pathogenicity of H. pylori.

Analysis of the Association between Fatigue and the Plasma Lipidomic Profile of Inflammatory Bowel Disease Patients.

Inflammatory bowel disease (IBD) is a chronic, relapsing noninfectious inflammatory condition of the intestinal tract with two main phenotypes, ulcerative colitis (UC) and Crohn's disease (CD), and globally increasing incidence and prevalence. Nearly 80% of the IBD patients with active disease and 50% of those with inactive disease suffer fatigue with significant impairment of their quality of life. Fatigue has been associated with multiple factors in IBD patients but, in most cases, no direct cause can be identified, and risk factors in clinically quiescent IBD are contradictory. Furthermore, as the assessment of fatigue is subjective, there is an unmet clinical need for fatigue biomarkers. In this explorative study, we analyzed the plasma lipidomic profiles of 47 quiescent UC and CD patients (23 fatigued, 24 nonfatigued) using ultraperformance liquid chromatography-time-of-flight mass spectrometry (UPLC-TOFMS). The results showed changes in lipids associated with fatigue and IBD. Significantly decreased levels of phosphatidylcholines, plasmanyls, sphingomyelins, lysophosphatidylcholines, phosphatidylethanolamines, phosphatidylinositols, phosphatidylserines, and eicosanoids were observed in patients with fatigue. Network and metabolic pathway analysis indicated a dysregulation of the arachidonic acid and glycerophospholipid metabolisms and the sphingolipid pathway. The protein-metabolite interaction network showed interactions between functionally related metabolites and proteins, displaying 40 disease-associated hidden proteins including ABDH4, GLTP, and LCAT.

Cross-sectional study of human coding- and non-coding RNAs in progressive stages of Helicobacter pylori infection.

Helicobacter pylori infects 4.4 billion individuals worldwide and is considered the most important etiologic agent for peptic ulcers and gastric cancer. Individual response to H. pylori infection is complex and depends on complex interactions between host and environmental factors. The pathway towards gastric cancer is a sequence of events known as Correa's model of gastric carcinogenesis, a stepwise inflammatory process from normal mucosa to chronic-active gastritis, atrophy, metaplasia and gastric adenocarcinoma. This study examines gastric clinical specimens representing different steps of the Correa pathway with the aim of identifying the expression profiles of coding- and non-coding RNAs that may have a role in Correa's model of gastric carcinogenesis. We screened for differentially expressed genes in gastric biopsies by employing RNAseq, microarrays and qRT-PCR. Here we provide a detailed description of the experiments, methods and results generated. The datasets may help other scientists and clinicians to find new clues to the pathogenesis of H. pylori and the mechanisms of progression of the infection to more severe gastric diseases. Data is available via ArrayExpress.

Droplet Digital PCR Detects Low-Density Infection in a Significant Proportion of Helicobacter Pylori-Negative Gastric Biopsies of Dyspeptic Patients.

INTRODUCTION: Helicobacter pylori-infected individuals may present low-density infection, undetectable by conventional tests such as histology, rapid urease test, or urea breath test. Droplet digital polymerase chain reaction (ddPCR) is more sensitive than other polymerase chain reaction methods. We aimed to evaluate the ability of ddPCR to detect H. pylori infection in patients diagnosed as negative by conventional tests. METHODS: Dyspeptic patients (n = 236) were tested for H. pylori by histology, urea breath test, and rapid urease test. Patients were classified as having 3 positive (n = 25, control group), 2 positive (n = 12), one positive (n = 41), or zero positive (n = 158) diagnostic tests. DNA was extracted from gastric biopsies. Triplicate ddPCR testing for each of the 16S rDNA, ureA, and vacA(s) genes was performed using a QX200 ddPCR system (Bio-Rad). A gene was considered positive when detected by at least 2 of 3 repeated ddPCRs. H. pylori positivity was defined as having 2 or more positive genes. RESULTS: All the biopsies of the control patients were positive for all 3 16S rDNA, ureA, and vacA(s) genes. H. pylori infection was detected in 57 (36%), 22 (54%), and 9 (75%) patients with zero, 1, and 2 positive diagnostic tests, respectively. The density of infection was 5, 121, 599, and 3,133 copies of H. pylori genome equivalents for patients with zero, 1, and 2 of 3 positive test results and for the control group, respectively. DISCUSSION: ddPCR detected low-density "occult" H. pylori infection in a significant proportion (36%) of patients diagnosed as negative by conventional methods. The number of conventional positive tests was related to the density of infection.

Prospective, study comparing the accuracy of two different stool antigen tests (Premier Platinum HpSA and novel ImmunoCard STAT rapid test) for the diagnosis of Helicobacter pylori infection / Estudio prospectivo y comparativo entre la exactitud de 2 pruebas de antígenos en heces (Premier Platinum HpSA® y el nuevo test rápido ImmunoCard® STAT) para el diagnóstico de la infección por Helicobacter pylori

BACKGROUND: At present only monoclonal EIA (enzyme-immunoassay) stool antigen-tests have obtained optimal accuracy in the diagnosis of Helicobacter pylori. Our aim was to evaluate the accuracy of two stool antigen-tests, the validated Premier Platinum HpSA PLUS (EIA test) and the newly available ImmunoCard STAT! HpSA HD (rapid test) for the initial diagnosis and the confirmation of eradication of H. pylori infection. PATIENTS AND METHODS: Patients with indication of H. pylori diagnosis, or confirmation after treatment were included. Data were coded to protect personal data and ensure blindness between tests. Accuracy was considered as coincident diagnosis with the gold standard (13C-urea breath test, UBT). The EIA was used as a bench standard. All stool tests were performed in duplicate. RESULTS: 264 patients completed the protocol (100 naïve, 164 post-eradication). Average age was 52 years, 61% women, 11% ulcer. Positive diagnoses by UBT were 41% for naïve and 17% for post-eradication. Overall ImmunoCard and EIA accuracies were respectively 91% (95%C. I. =88-94%) and 89% (86-93%), sensitivities 72% (67-78%) and 72% (67-78%), and specificities 98% (96-100%), and 95% (92-97%). Concordance between ImmunoCard and EIA was 95% (93-98%). DISCUSSION: Our results indicate that the newly available ImmunoCard rapid stool antigen-test achieves 90% accuracy, with high specificity but suboptimal sensitivity. The ImmunoCard attained equivalent accuracies as the EIA bench standard, with 95% concordance

ANTECEDENTES: En la actualidad, únicamente los métodos de detección de antígenos en heces monoclonales basados en enzimoinmunoanálisis (ELISA) han obtenido una adecuada precisión para el diagnóstico de la infección por Helicobacter pylori. Nuestro objetivo fue evaluar la exactitud (sensibilidad y especificidad) de 2 métodos de antígenos en las heces, el previamente validado Premier Platinum HpSA® PLUS (ELISA) y el nuevo ImmunoCard® STAT! HpSA® HD (test rápido), para el diagnóstico inicial y la confirmación de la erradicación de la infección por H. pylori. PACIENTES Y MÉTODOS: Se incluyeron pacientes en los que estaba indicado el diagnóstico inicial de la infección por H. pylori o su confirmación tras el tratamiento. Los datos fueron codificados y los evaluadores de ambos test fueron ciegos para los resultados de las pruebas diagnósticas. El resultado principal fue la coincidencia con el resultado del patrón oro (prueba del aliento con 13C-urea). Los test en heces se realizaron por duplicado. RESULTADOS: Doscientos sesenta y cuatro pacientes completaron el protocolo (100 naïve, 164 posterradicación). La edad media fue de 52 años, el 61% fueron mujeres y el 11% tenían úlcera péptica. La prueba del aliento fue positiva en el 41% de los pacientes naïve y en el 17% posterradicación. La exactitud global del método rápido y del ELISA fue, respectivamente, 91% (IC 95%: 88-94%) y 89% (86-93%), la sensibilidad 72% (67-78%) y 72% (67-78%), y la especificidad 98% (96-100%) y 95% (92-97%). La concordancia entre el método ImmunoCard® y ELISA fue del 95% (93-98%). DISCUSIÓN: El nuevo método rápido de antígenos en heces (ImmunoCard® STAT! HpSA® HD) tiene una exactitud diagnóstica del 90%, con una elevada especificidad, pero una sensibilidad insuficiente. El método ImmunoCard® tiene una exactitud equivalente al método ELISA estándar, con una concordancia del 95%

Detection of Helicobacter pylori Microevolution and Multiple Infection from Gastric Biopsies by Housekeeping Gene Amplicon Sequencing.

Despite the great efforts devoted to research on Helicobacter pylori, the prevalence of single-strain infection or H. pylori mixed infection and its implications in the mode of transmission of this bacterium are still controversial. In this study, we explored the usefulness of housekeeping gene amplicon sequencing in the detection of H. pylori microevolution and multiple infections. DNA was extracted from five gastric biopsies from four patients infected with distinct histopathological diagnoses. PCR amplification of six H. pylori-specific housekeeping genes was then assessed on each sample. Optimal results were obtained for the cgt and luxS genes, which were selected for amplicon sequencing. A total of 11,833 cgt and 403 luxS amplicon sequences were obtained, 2042 and 112 of which were unique sequences, respectively. All cgt and luxS sequences were clustered at 97% to 9 and 13 operational taxonomic units (OTUs), respectively. For each sample from a different patient, a single OTU comprised the majority of sequences in both genes, but more than one OTU was detected in all samples. These results suggest that multiple infections with a predominant strain together with other minority strains are the main way by which H. pylori colonizes the human stomach.

Prospective, study comparing the accuracy of two different stool antigen tests (Premier Platinum HpSA and novel ImmunoCard STAT! rapid test) for the diagnosis of Helicobacter pylori infection.

BACKGROUND: At present only monoclonal EIA (enzyme-immunoassay) stool antigen-tests have obtained optimal accuracy in the diagnosis of Helicobacter pylori. Our aim was to evaluate the accuracy of two stool antigen-tests, the validated Premier Platinum HpSA PLUS (EIA test) and the newly available ImmunoCard STAT! HpSA HD (rapid test) for the initial diagnosis and the confirmation of eradication of H. pylori infection. PATIENTS AND METHODS: Patients with indication of H. pylori diagnosis, or confirmation after treatment were included. Data were coded to protect personal data and ensure blindness between tests. Accuracy was considered as coincident diagnosis with the gold standard (13C-urea breath test, UBT). The EIA was used as a bench standard. All stool tests were performed in duplicate. RESULTS: 264 patients completed the protocol (100 naïve, 164 post-eradication). Average age was 52 years, 61% women, 11% ulcer. Positive diagnoses by UBT were 41% for naïve and 17% for post-eradication. Overall ImmunoCard and EIA accuracies were respectively 91% (95%C.I.=88-94%) and 89% (86-93%), sensitivities 72% (67-78%) and 72% (67-78%), and specificities 98% (96-100%), and 95% (92-97%). Concordance between ImmunoCard and EIA was 95% (93-98%). DISCUSSION: Our results indicate that the newly available ImmunoCard rapid stool antigen-test achieves 90% accuracy, with high specificity but suboptimal sensitivity. The ImmunoCard attained equivalent accuracies as the EIA bench standard, with 95% concordance.

Genetic variation analysis in a follow-up study of gastric cancer precursor lesions confirms the association of MUC2 variants with the evolution of the lesions and identifies a significant association with NFKB1 and CD14.

Gastric carcinogenesis proceeds through a series of gastric cancer precursor lesions (GCPLs) leading to gastric cancer (GC) development. Although Helicobacter pylori infection initiates this process, genetic factors also play a role. We previously reported that genetic variability in MUC2 is associated with the evolution of GCPLs. In order to replicate previous results in an independent sample series and to explore whether genetic variability in other candidate genes plays a role in the evolution of GCPL, genomic DNA from 559 patients with GCPLs, recruited from 9 Spanish hospitals and followed for a mean of 12 years, was genotyped for 141 SNPs in 29 genes. After follow-up, 45.5% of the lesions remained stable, 37% regressed and 17.5% progressed to a more severe lesion. Genetic association with the evolution of the lesions (progression or regression) was analyzed by multinomial and binomial logistic regression. After correction for multiple comparisons, the results obtained confirmed the inverse association between MUC2 variants and the regression of the lesions. A significant association was also observed between NFKB1 and CD14 variants and the evolution of the lesions; interestingly, this association was with both progression and regression in the same direction, which could reflect the dual role of inflammation in cancer. Stratified analyses according to H. pylori virulence factors indicated some significant and differential effects but none of them passed the FDR test. These results confirm that genetic variability in MUC2, NFKB1 and CD14 may have a role in the evolution of the GCPLs along time and in gastric carcinogenesis.

Expression profile of circulating microRNAs in the Correa pathway of progression to gastric cancer.

BACKGROUND: Helicobacter pylori infection causes long-term chronic active gastritis, a risk factor for the intestinal and diffuse forms of gastric cancer. Most gastric cancers develop in a stepwise progression from chronic active gastritis to precursor lesions of gastric cancer. The early detection of gastric cancer improves survival. Studies with recent evidence have proposed circulating-microRNAs as biomarkers of cancer. OBJECTIVE: The purpose of this study was to explore the circulating-microRNA profile from H. pylori infection to gastric adenocarcinoma. METHODS: One hundred and twenty-three patients were enrolled and assigned to the discovery or the validation sets. In the discovery phase, circulating-microRNAs were measured by dye-based quantitative polymerase chain reaction and a selection of circulating-microRNAs was validated by probe-based quantitative polymerase chain reaction. A quality control protocol was used. RESULTS: One hundred and sixty-seven circulating-microRNAs were detected. Precursor lesions of gastric cancer and gastric cancer patients showed the downregulation of eight and five circulating-microRNAs, respectively. We further validated the deregulation of miR-196a-5p in precursor lesions of gastric cancer and the deregulation of miR-134-5p, miR-144-3p and miR-451a in gastric cancer. However, circulating-microRNAs exhibited moderate diagnostic performance due to the overlap of circulating-microRNA expression between non-cancer and cancer patients. miR-144-3p/miR-451a expression levels were correlated. Interestingly, these microRNAs are in 17q11.2, a site of rearrangements associated with gastric cancer. CONCLUSION: Circulating-microRNAs are deregulated in precancerous and gastric cancer patients but efforts are needed to improve their diagnostic accuracy.

Application of Individual qPCR Performance Parameters for Quality Control of Circulating MicroRNA Data.

Although circulating miRNAs are promising candidates for biomarkers, several challenges must be overcome before miRNAs can be used for diagnosis and monitoring. One is quality control for the RNA extraction and quantification process. RNA quality control techniques are unsuitable as circulating miRNAs are in the fM range. Additionally, biofluids may contain inhibitors of the reverse transcriptase and polymerase enzymes, which may survive RNA purification. Herein, we describe the protocol we have used to check the robustness of miRNA purification and measurement by the addition of spike-ins and by evaluating the quality of the qPCR data, respectively.

Plasma sample based analysis of gastric cancer progression using targeted metabolomics.

Gastric carcinogenesis is a multifactorial process described as a stepwise progression from non-active gastritis (NAG), chronic active gastritis (CAG), precursor lesions of gastric cancer (PLGC) and gastric adenocarcinoma. Gastric cancer (GC) 5-year survival rate is highly dependent upon stage of disease at diagnosis, which is based on endoscopy, biopsy and pathological examinations. Non-invasive GC biomarkers would facilitate its diagnosis at early stages leading to improved GC prognosis. We analyzed plasma samples collected from 80 patients diagnosed with NAG without H. pylori infection (NAG-), CAG with H. pylori infection (CAG+), PLGC and GC. A panel of 208 metabolites including acylcarnitines, amino acids and biogenic amines, sphingolipids, glycerophospholipids, hexoses, and tryptophan and phenylalanine metabolites were quantified using two complementary quantitative approaches: Biocrates AbsoluteIDQ®p180 kit and a LC-MS method designed for the analysis of 29 tryptophan pathway and phenylalanine metabolites. Significantly altered metabolic profiles were found in GC patients that allowing discrimination from NAG-, CAG+ and PLGC patients. Pathway analysis showed significantly altered tryptophan and nitrogen metabolic pathways (FDR P < 0.01). Three metabolites (histidine, tryprophan and phenylacetylglutamine) discriminated between non-GC and GC groups. These metabolic signatures open new possibilities to improve surveillance of PLGC patients using a minimally invasive blood analysis.

Metabolomic Analysis of Gastric Cancer Progression within the Correa's Cascade Using Ultraperformance Liquid Chromatography-Mass Spectrometry.

Gastric cancer (GC) is among the most common cancers worldwide. Gastric carcinogenesis is a multistep and multifactorial process beginning with chronic gastritis induced by Helicobacter pylori (H. pylori) infection. This process is often described via a sequence of events known as Correas's cascade, a stepwise progression from nonactive gastritis, chronic active gastritis, precursor lesions of gastric cancer (atrophy, intestinal metaplasia, and dysplasia), and finally adenocarcinoma. Our aim was to identify a plasma metabolic pattern characteristic of GC through disease progression within the Correa's cascade. This study involved the analysis of plasma samples collected from 143 patients classified in four groups: patients with nonactive gastritis and no H. pylori infection, H. pylori infected patients with chronic active gastritis, infected or noninfected patients with precursor lesions of gastric cancer, and GC. Independent partial least-squares-discriminant binary models of UPLC-ESI(+)-TOFMS metabolic profiles, implemented in a decision-directed acyclic graph, allowed the identification of tryptophan and kynurenine as discriminant metabolites that could be attributed to indoleamine-2,3-dioxygenase upregulation in cancer patients leading to tryptophan depletion and kynurenine metabolites generation. Furthermore, phenylacetylglutamine was also classified as a discriminant metabolite. Our data suggest the use of tryptophan, kynurenine, and phenylacetylglutamine as potential GC biomarkers.

Usefulness of Housekeeping Genes for the Diagnosis of Helicobacter pylori Infection, Strain Discrimination and Detection of Multiple Infection.

BACKGROUND: Helicobacter pylori infects human stomachs of over half the world's population, evades the immune response and establishes a chronic infection. Although most people remains asymptomatic, duodenal and gastric ulcers, MALT lymphoma and progression to gastric cancer could be developed. Several virulence factors such as flagella, lipopolysaccharide, adhesins and especially the vacuolating cytotoxin VacA and the oncoprotein CagA have been described for H. pylori. Despite the extensive published data on H. pylori, more research is needed to determine new virulence markers, the exact mode of transmission or the role of multiple infection. MATERIALS AND METHODS: Amplification and sequencing of six housekeeping genes (amiA, cgt, cpn60, cpn70, dnaJ, and luxS) related to H. pylori pathogenesis have been performed in order to evaluate their usefulness for the specific detection of H. pylori, the genetic discrimination at strain level and the detection of multiple infection. A total of 52 H. pylori clones, isolated from 14 gastric biopsies from 11 patients, were analyzed for this purpose. RESULTS: All genes were specifically amplified for H. pylori and all clones isolated from different patients were discriminated, with gene distances ranged from 0.9 to 7.8%. Although most clones isolated from the same patient showed identical gene sequences, an event of multiple infection was detected in all the genes and microevolution events were showed for amiA and cpn60 genes. CONCLUSIONS: These results suggested that housekeeping genes could be useful for H. pylori detection and to elucidate the mode of transmission and the relevance of the multiple infection.

Good diagnostic accuracy of a chemiluminescent immunoassay in stool samples for diagnosis of Helicobacter pylori infection in patients with dyspepsia.

Laboratory-based chemiluminescence immunoassays (CLIA) are widely used in clinical laboratories. Some years ago, a CLIA test was developed for the detection of Helicobacter pylori in stool samples, known as LIAISON H. pylori SA, but little information on its use has been reported. To evaluate the accuracy of the LIAISON H. pylori SA assay for diagnosing H. pylori infection prior to eradication treatment. Diagnostic reliability was evaluated in 252 untreated consecutive patients with dyspepsia. The gold standard for diagnosing H. pylori infection was defined as the concordance of the rapid urease test (RUT), histopathology and urea breath test (UBT). The CLIA assay was performed according to the manufacturer's instructions. Sensitivity, specificity, positive and negative predictive values, and 95% CIs were calculated. According to the gold standard selected, 121 patients were positive for H. pylori infection and 131 negative. LIAISON H. pylori SA had a sensitivity of 90.1% and a specificity of 92.4%, with positive and negative predictive values of 91.6% and 90.1%, respectively. The accuracy of the LIAISON H. pylori SA chemiluminescent diagnostic assay seems comparable to that of ELISA or the best-performing LFIAs. Its sensitivity and specificity, however, seem slightly lower than those of histology, RUT or UBT. The advantages of the assay are that it is cheap, automated, and minimally labor-intensive.

Diagnostic accuracy of three monoclonal stool tests in a large series of untreated Helicobacter pylori infected patients.

OBJECTIVES: Immunochromatographic tests need to be improved in order to enhance their reliability. Recently, several new kits have appeared on the market. The objective was to evaluate the diagnostic accuracy of three monoclonal rapid stool tests - the new Uni-Gold™ H.pylori Antigen (Trinity Biotech, Ireland), the RAPID Hp StAR (Oxoid Ltd., UK) and the ImmunoCard STAT! HpSA (Meridian Diagnostics, USA) - for detecting H. pylori infection prior to eradication treatment. DESIGN AND METHODS: Diagnostic accuracy (sensitivity and specificity) and reliability (concordance between observers) were evaluated in 250 untreated consecutive dyspeptic patients. The gold standard for diagnosing H. pylori infection was defined as the concordance of two or more of rapid urease test (RUT), histopathology and urease breath test (UBT) or positive culture in isolation. Readings of immunochromatographic tests were performed by two different observers. Sensitivity, specificity, positive and negative predictive values and 95% confidence intervals were calculated. Sensitivity and specificity were compared using the McNemar test. RESULTS: The three tests showed a good correlation, with Kappa values>0.9. RAPID Hp StAR had a sensitivity of 91%-92% and a specificity ranging from 77% to 85%. Its sensitivity was higher than that of Uni-Gold™ H.pylori Antigen and ImmunoCard STAT! HpSA (p<0.01). Uni-Gold™ H.pylori Antigen kit showed a sensitivity of 83%, similar to ImmunoCard STAT! HpSA. Specificity of Uni-Gold™ H.pylori Antigen approached 90% (87-89%) and was superior to that of RAPID Hp StAR (p<0.01). CONCLUSIONS: Uni-Gold™ H.pylori Antigen and ImmunoCard STAT! HpSA present similar levels of diagnostic accuracy. RAPID Hp StAR was the most sensitive but less reliable of the three immunochromatographic stool tests. None are as accurate and reliable as UBT, RUT and histology.

Incomplete type of intestinal metaplasia has the highest risk to progress to gastric cancer: results of the Spanish follow-up multicenter study.

BACKGROUND AND AIM: In high or moderate risk populations, periodic surveillance of patients at risk of progression from gastric precursor lesions (PL) to gastric cancer (GC) is the most effective strategy for reducing the burden of GC. Incomplete type of intestinal metaplasia (IIM) may be considered as the best candidate, but it is still controversial and more research is needed. To further assess the progression of subtypes of IM as predictors of GC occurrence. METHODS: A follow-up study was carried-out including 649 patients, diagnosed with PL between 1995-2004 in 9 participating hospitals from Spain, and who repeated the biopsy during 2011-2013. Medical information and habits were collected through a questionnaire. Based on morphology, IM was sub-classified as complete (small intestinal type, CIM) and incomplete (colonic type, IIM). Analyses were done using Cox (HR) models. RESULTS: At baseline, 24% of patients had atrophic gastritis, 38% CIM, 34% IIM, and 4% dysplasia. Mean follow-up was 12 years. 24 patients (3.7%) developed a gastric adenocarcinoma during follow-up. The incidence rate of GC was 2.76 and 5.76 per 1,000 person-years for those with CIM and IIM, respectively. The HR of progression to CG was 2.75 (95% CI 1.06-6.26) for those with IIM compared with those with CIM at baseline, after adjusting for sex, age, smoking, family history of GC and use of NSAIDs. CONCLUSIONS: IIM is the PL with highest risk to progress to GC. Sub-typing of IM is a valid procedure for the identification of high risk patients that require more intensive surveillance.