Real-time determination of gastric juice pH with EndoFaster® for atrophic gastritis assessment

BACKGROUND

In patients with atrophic gastritis involving gastric body mucosa the pH value of gastric juice is distinctly increased, so that pH assessment would allow predict this precancerous lesion. We tested whether EndoFaster® - a device allowing real-time pH measure and H. pylori diagnosis - may optimize the need of taking gastric biopsies.

METHODS

In this prospective, multicentre study, the accuracy of EndoFaster® for ruling out gastric atrophy involving corporal mucosa was assessed. Real-time pH and ammonium determination was performed by aspirating 3-6 ml gastric juice during endoscopy. Histology performed on 5 standard gastric biopsies was used as gold standard.

RESULTS

A total of 1008 consecutive patients were observed in 12 centres. At histology, gastric body mucosa atrophy/metaplasia was detected in 65 (6.4%) cases, and a pH value >4.5 in the gastric juice was observed in 150 patients. The values of EndoFaster® performance in predicting the presence of atrophic gastritis were as follow: 51% sensitivity, 84% specificity, 18% PPV, 96% NPV, and 82% accuracy. The NPV value was not distinctly affected by neither ongoing proton pump inhibitor therapy nor H. pylori infection. By considering also data of ammonium concentrations, the values of EndoFaster® in detecting extensive atrophy on gastric mucosa were 74% sensitivity, 84% specificity, 24% PPV, 98% NPV, and 83% accuracy.

CONCLUSION

The very high NPV of EndoFaster® might allow to safely rule out presence of atrophic gastritis, reducing the need of taking gastric biopsies in unselected patients managed in clinical practice.

Real-time gastric juice analysis with EndoFaster for H. pylori diagnosis: a large, multicentre study

BACKGROUND

Helicobacter pylori infection is the main cause of the most frequent gastroduodenal diseases. Because its prevalence is decreasing in developed countries, gastric biopsies are negative in several patients. By measuring ammonium in the gastric juice, EndoFaster allows to exclude H. pylori infection during endoscopy. This study aimed to assess the accuracy of device versions working with either 6 ml or 3 ml of gastric juice.

STUDY DESIGN

This prospective study involved 12 endoscopic units. During endoscopy, EndoFaster testing was performed and standard five gastric biopsies were taken. The accuracy was calculated by considering histological assessment as the gold standard for H. pylori diagnosis.

RESULTS

Gastric juice analysis was attempted in 1279 patients, but it failed in 131 (15.5%) and in 10 (2.3%), with the 6 ml and the 3 ml device, respectively (P < 0.001). Overall, EndoFaster detected H. pylori infection with an 86.3% sensitivity, 83.3% specificity, 52.7% positive predictive value, 96.6% negative predictive value and 83.8% accuracy. The performance was not affected either by ongoing proton pump inhibitor therapy or a previous H. pylori eradication. No significant difference in accuracy emerged between the two versions of the device.

CONCLUSION

The novel version of the EndoFaster device operating with 3 ml gastric juice may be performed in virtually all patients, and it allows excluding H. pylori infection with a very high accuracy. Gastric biopsies can be avoided in a definite portion of cases without endoscopic lesions or other clinical indications.

Evaluation of Antibiotic Resistance of Helicobacter pylori Strains Isolated in Bari, Southern Italy, in 2017-2018 by Phenotypic and Genotyping Methods

Objective: Helicobacter pylori antibiotic resistance is a constantly evolving process and local surveillance is warranted to guide clinicians in the choice of therapy. Materials and Methods: Antibiotic susceptibility testing was performed by E-test on 92 H. pylori strains, and resistance to clarithromycin and levofloxacin was also evaluated using a commercially available genotyping method. Results: In naïve patients the resistance to clarithromycin, levofloxacin, and metronidazole was 37.7%, 26.2%, and 16.4%, respectively, significantly lower than the percentage found in treated patients. Concomitant resistance to ≥2 antibiotics was also observed in naïve patients. The A2143G mutation of the 23S-rRNA gene was the most frequently detected, also in naïve patients. The highest minimum inhibitory concentration (MIC)₅₀ value (256 mg/L) was associated with A2142 mutations in all the patients carrying them. For levofloxacin resistance a mutation in codon 87 was detected in 63.9% and in codon 91 in 36.1% of the H. pylori strains, without significant differences in the patients groups. A mutation in codon 87 was associated with the highest MIC₅₀ value (32 mg/L). Conclusions: In our area, a high prevalence of H. pylori primary resistance was detected; these rates were higher in patients who had experienced failure of several courses of therapy. A better knowledge of the local epidemiology of resistance, and the genotypes responsible, will improve the H. pylori eradication rates.

Barrett's esophagus and esophageal cancer: an overview

Although esophageal cancer (EC) is the eighth most common cancer in several European countries, it is one of deadliest worldwide. The most frequent predisposing factor implicated in its development is Barrett's esophagus (BE), an acquired metaplastic transformation of the esophageal lining cells from normal squamous epithelium into specialised or intestinal-like columnar epithelium. The major risk factor for BE is gastroesophageal reflux disease. Although BE is in itself a benign and often asymptomatic disorder, its clinical importance stems from the recognition that it represents the main precursor lesion for the development of esophageal adenocarcinoma (AC), a tumor that is rapidly increasing especially in developed countries and is associated with a low survival rate. This paper provides an overview of the epidemiology and natural history of BE as well as of the possible pathogenetic mechanisms underlying the development of BE and its progressive transition to AC. New diagnostic tests are described, recommendations for screening and surveillance are provided and surgical and ablative procedures to treat dysplastic lesions and early neoplasia are discussed. Claimed chemopreventive agents and biomarkers that in the near future may help identify people with a higher risk of EC are also considered.

Infliximab therapy downregulation of basic fibroblast growth factor/syndecan 1 link: a possible molecular pathway of mucosal healing in ulcerative colitis

BACKGROUND

It is known that syndecan 1 in inflammatory bowel diseases is able to migrate from epithelial basolateral site to the stromal area and apical surface of epithelium with a consequent activation and modulation of basic fibroblast growth factor (bFGF), and this process sustains mucosal healing of ulcers. On the other hand, tumour necrosis factor (TNF) α mucosal levels are directly related to the entity of the damage in these disorders. Aim of the study A 'post-hoc' retrospective study was performed to estimate mucosal TNF α in rectal biopsies of subjects with ulcerative colitis (UC) before and after effective infliximab therapy and its relationship with syndecan 1, bFGF and endoscopic mucosal healing.

MATERIAL AND METHODS

Paraffin-embedded rectal samples from 12 patients with UC responders to infliximab were analysed for TNF α, syndecan 1 and bFGF before and 6 months after therapy using a real-time reverse transcriptase polymersase chain reaction. Additionally, syndecan 1 location was evaluated by immunohistochemistry. Samples from 12 subjects with irritable bowel symptoms without endoscopic/histological abnormalities represented the control group. Mucosal healing induced by the treatment was defined by an endoscopic Mayo subscore changing from 2-3 to 0. ANOVA plus Student-Newman-Keuls was used for statistical analysis.

RESULTS

The authors found that in the active disease, an increase in TNF α (p<0.001) is accompanied by raised levels of both syndecan 1 (p<0.005) and bFGF (p<0.005) compared with the control group. Infliximab-induced TNF α decrease to levels similar to controls is associated with both endoscopic mucosal healing and adhesion molecule/growth factor significant reduction. Additionally, syndecan 1 location, which is predominant in the stromal cells and apical epithelium in the active disorder, is quite exclusively located at the basolateral epithelial area in both healed mucosa and controls.

CONCLUSIONS

Balanced interaction among TNF α inhibition by infliximab, syndecan 1 migration, bFGF repair modulation and final adhesion molecule reversal to its normal location might represent a suitable molecular pathway of endoscopic mucosal healing in UC.

Clarithromycin-resistant genotypes and eradication of Helicobacter pylori

OBJECTIVE

To compare the eradication rates among the different point mutations and the efficacy of triple therapy and a sequential regimen according to genotypic resistance.

STUDY DESIGN

Post hoc retrospective cohort study in a tertiary referral center for pediatric gastroenterology in southern Italy. All 168 children who were positive for Helicobacter pylori were enrolled. Patients had received clarithromycin-based 7-day triple therapy (73 children) or 10-day sequential therapy regimen (95 children). Real-time polymerase chain reaction for assessing clarithromycin resistance was performed on sections of paraffin-embedded gastric biopsy samples.

RESULTS

H pylori eradication was achieved in 16 of 32 (50%) children with the A2143G mutation, in 8 of 10 patients with either A2142G or A2142C strains (80%), and in 112 of 116 children with susceptible strains (88.9%). The presence of A2143G mutation was associated with a lower cure rate compared with the rate in the absence of this mutation (50% vs. 89%; P = .001). The sequential regimen achieved a higher cure rate than triple therapy in patients with A2143G mutant strains (80% vs nil; P < .001).

CONCLUSIONS

The A2143G mutation confers higher risk of treatment failure. Sequential regimen has higher efficacy than standard therapy, even in children with A2143G mutatant strains.

ER-beta expression in large bowel adenomas: implications in colon carcinogenesis

BACKGROUND

A pivotal role of oestrogen receptor-beta has been suggested in colon carcinogenesis in humans. However, few data are available on oestrogen receptor-beta in colorectal pre-cancerous lesions.

AIM

In the present study, we evaluated oestrogen receptor-beta expression and its possible correlation with proliferative activity and apoptosis in colorectal adenomas and normal colon tissue.

PATIENTS/METHODS

Adenomatous tissue from 25 patients with colonic polyps, and normal tissue from 25 controls were used. Oestrogen receptor-beta expression, colonocyte proliferation (expressed as PCNA positivity) and apoptosis were evaluated.

RESULTS

In adenomatous tissue, a significant reduction of oestrogen receptor-beta was observed compared to normal mucosa (10.1+/-5.5% vs. 44.2+/-13.7; p<0.03), while the expression of oestrogen receptor-alpha remained unvaried. Cell proliferative activity significantly increased in adenomatous tissue compared to normal mucosa (59.3+/-7.1 vs. 18.5+/-8.8; p<0.0001), doubling the PCNA/apoptosis ratio. An inverse correlation was found between oestrogen receptor-beta and PCNA expression in adenomas (r=-0.81), a datum confirmed by confocal microscopy evaluation.

CONCLUSIONS

Our data demonstrate, for the first time, a significant reduction of oestrogen receptor-beta expression already in the pre-cancerous phase of colon carcinogenesis. This suggests a role of selective oestrogen receptor-beta agonists in the prevention of colorectal cancer.

Differential immunohistochemical expression of syndecan-1 and tumor necrosis factor alpha in colonic mucosa of patients with Crohn's disease

Tumor necrosis factor alpha (TNFalpha) in intestinal mucosa plays a key role in the inflammation characterizing Crohn's disease (CD). Moreover, adhesion molecule syndecan-1 mediates the maintenance of mucosal integrity and supports tissue repair. Therefore, our aim in this study was to correlate simultaneous expression of TNFalpha and syndecan-1 in patients affected by CD. Biopsies from 10 patients with CD of large bowel and 10 subjects with irritable bowel syndrome (controls) were studied by immunohistochemical detection of both TNFalpha and syndecan-1 on successive serial sections. Overall labeling index (OLI) was indicated by the percentage of positive stromal (i.e., nonepithelial) cells/1000 counted in randomized fields, whereas selected labeling index (SLI) was represented by the simultaneous evaluation of both molecules in a same single selected field of each specimen. TNFalpha and syndecan-1 OLI were significantly higher in CD compared with controls, while SLI showed an inverse relationship between the molecules in CD which was not observed in controls. Epithelial syndecan-1 cytoplasmatic staining of superficial epithelium was associated with loss of basolateral staining in the crypts and high stromal TNFalpha in CD. In conclusion, TNFalpha and syndecan-1 expression is increased in the intestinal mucosa of patients with CD. However, the expression of the two molecules is inversely related when a single field is considered, these data supporting the possibility of a downregulation exerted by TNFalpha.

Gastric epithelial cell proliferation and ras oncogene p21 expression in first-degree relatives of gastric cancer patients: a case-control study

OBJECTIVES

Individuals with a family history of gastric cancer have an increased risk of developing such neoplasia. This study aimed to assess epithelial cell proliferation and ras oncogene mutation in such individuals.

METHODS

Twenty dyspeptic, first-degree relatives of patients with gastric cancer and 20 matched controls were enrolled. Endoscopy with biopsies was performed in all cases. Gastric specimens were used to look for Helicobacter pylori infection and to assess both epithelial cell proliferation and ras oncogene expression by immunohistochemistry.

RESULTS

Cell proliferation values were not significantly different between the patient and control groups (18.1 +/- 7.1 versus 18.9 +/- 7.4; P = 0.7). Overall, ras mutation was detected in five out of 40 cases, and its distribution was similar between patients and controls (20 versus 10%; P = 0.9), as well as between H. pylori-positive and negative patients (22 versus 9%; P = 0.2). Cell proliferation values tended to be higher in cases with ras mutation than in those without (25.2 +/- 9.4 versus 16.8 +/- 5.8; P = 0.08). Cell proliferation values were significantly higher in H. pylori-positive cases compared with uninfected cases, in both patient (24.7 +/- 4.7 versus 12.5 +/- 2.4; P = 0.0003) and control (25.9 +/- 4.8 versus 13.3 +/- 2.8; P = 0.0003) groups.

CONCLUSIONS

Both gastric cell proliferation values and ras mutation prevalence did not differ between first-degree relatives of gastric cancer patients and controls. H. pylori infection similarly increased the proliferation index of gastric mucosa in both groups.

Clarithromycin-resistant genotypes and eradication of Helicobacter pylori

BACKGROUND

Three point mutations (A2143G, A2142G, and A2142C) have been involved in Helicobacter pylori clarithromycin resistance.

OBJECTIVE

To compare the eradication rates among the different point mutations and the efficacy of triple therapy and a sequential regimen according to genotypic resistance.

DESIGN

Post hoc subgroup study from a multicenter, randomized trial.

SETTING

Two hospitals in central and southern Italy between January and December 2001.

PATIENTS

156 patients with H. pylori infection.

MEASUREMENTS

Real-time polymerase chain reaction for assessing clarithromycin resistance; histology, rapid urease test, and 13C-urea breath test at entry and after 4 to 6 weeks.

INTERVENTION

7-day triple therapy (20 mg of rabeprazole, 500 mg of clarithromycin, and 1 g of amoxicillin) in 75 patients or a 10-day sequential regimen (20 mg of rabeprazole plus 1 g of amoxicillin for 5 days and 20 mg of rabeprazole, 500 mg of clarithromycin, and 500 mg of tinidazole for the remaining 5 days) in 81 patients. All drugs were given twice daily.

RESULTS

Helicobacter pylori infection was eradicated in 11 of 23 patients (48%) with the A2143G mutation and in 14 of 15 patients (93%) with either A2142G or A2142C strains (difference, 45 percentage points [95% CI, 15 to 65 percentage points]; P = 0.004). The sequential regimen achieved a higher cure rate than triple therapy in A2143G mutate strains (difference, 49 percentage points [CI, 8 to 72 percentage points]; P = 0.024).

LIMITATIONS

The post hoc substudy design may require further confirmation. Other limitations are the accessibility to the tool and the cost of investigations (70 euros per patient).

CONCLUSIONS

The A2143G mutation seemed to be associated with a very low eradication rate. The sequential regimen achieved a higher cure rate than standard therapy even in patients with these strains.

Lupus Nephritis Improvement After Anti‐tumor Necrosis Factor Alpha Monoclonal Antibody (Infliximab) Treatment for Crohn's Disease: A Case Report

Association between Crohn's disease (CD) and lupus nephritis is very rare and, to the best of our knowledge, it has been described only once. We report here a clinical case of CD occurred in a young woman 8 years after a diagnosis of lupus nephritis according to clinical, laboratory and histological criteria. CD was unresponsive to steroids and immunosuppressants and, therefore, the patient was treated with anti-tumour necrosis factor alpha monoclonal antibody (Infliximab). This therapy led to the remission of both CD (50% of Crohn's Disease Activity Index--CDAI--decrease) and lupus nephritis (disappearance of pyuria in absence of infection, significant increase of serum albumin and improvement of renal function tests). The immunological background of both diseases has to be taken into account to explain either the association of the two disorders or the therapeutic response. Moreover, this clinical case confirms and extends the concept that in patients with CD a more accurate detection of autoimmune associated disorders is required.

Sequential treatment for Helicobacter pylori does not share the risk factors of triple therapy failure

BACKGROUND

Predicting factors for the outcome of conventional Helicobacter pylori triple therapy have been identified. Of these, the presence of the CagA gene is a strong predictor of successful treatment. Our preliminary data show that this factor becomes irrelevant when sequential therapy is used.

AIM

To identify predicting factors for the outcome of H. pylori eradication using two therapeutic schemes (triple and sequential) of equal duration (10 days).

METHODS

Ninety-six patients with H. pylori infection were randomly assigned to receive one of the following therapeutic schemes: group A: rabeprazole (20 mg b.d.) plus amoxicillin (1 g b.d.) for 5 days, followed by rabeprazole (20 mg b.d.) plus tinidazole (500 mg b.d.) and clarithromycin (500 mg b.d.) for a further 5 days; group B: rabeprazole (20 mg b.d.) plus amoxicillin (1 g b.d.) and clarithromycin (500 mg b.d.) for 10 days. Age, sex, smoking, endoscopic and histological findings, and CagA and VacA status were considered as candidates for a model of multivariate analysis which used therapeutic outcome as the dependent variable. CagA and VacA status were assessed by polymerase chain reaction on DNA isolated from gastric antral specimens.

RESULTS

The sequential scheme was significantly more effective than prolonged triple therapy (P < 0.05). Smoking (P < 0.001) and the absence of the CagA gene (P < 0.05) were significantly associated with the failure of triple therapy, but the effectiveness of sequential treatment was not predicted by these factors.

CONCLUSION

Our data suggest that sequential therapy is not affected by bacterial and host factors which have, until now, predicted the outcome of conventional eradication treatments.

Tumor necrosis factor alpha and apoptosis in Helicobacter pylori related progressive gastric damage: a possible mechanism of immune system involvement in epithelial turnover regulation

Helicobacter pylori (HP) related inflammation is mediated by tumour necrosis factor alpha (TNFalpha), which "in vitro" increases epithelial apoptosis in response to infection. In the early stages of HP gastritis, a raised epithelial apoptosis occurs; this phenomenon becomes less evident with progression towards intestinal metaplasia. Aim of our study was to analyze "in vivo" mucosal TNFalpha in relation to epithelial apoptosis in the progression of HP related histological damage. Antral biopsies from 20 HP positive patients were retrospectively studied: 10 with and 10 without intestinal metaplasia (IM and CG group respectively); samples of 10 dyspeptics with normal HP negative stomach (N) were used as control. The following parameters were evaluated by immunohistochemistry: 85 kDa caspase-cleaved fragment (p85) of human poly (ADP-ribose) polymerase (PARP) labelling index (LI) as marker of apoptosis and TNFalpha LI in stromal cells as marker of inflammatory response. Both epithelial apoptosis and mucosal TNFalpha expression were higher in chronic active gastritis compared to intestinal metaplasia and controls (PARP and TNFalpha LI: CG > IM > N; ANOVA & Student-Neumann-Keuls; p < 0.05 and p < 0.01, respectively). Pearson's coefficient showed a significant correlation between PARP and TNFalpha LI in IM and CG groups. Our data show that mucosal TNFalpha, similarly to what suggested "in vitro", may be related "in vivo" to epithelial apoptosis thus suggesting a possible mechanism for immune system involvement in the control of gastric epithelial turnover.

Second harmonic imaging improves trans-abdominal ultrasound detection of biliary sludge in 'idiopathic' pancreatitis

BACKGROUND

Recently, biliary sludge has been strongly correlated with 'idiopathic pancreatitis'. It is often diagnosed by trans-abdominal ultrasonography, despite the low sensitivity of this investigation. New scanners, using second harmonic imaging, may improve the quality of the echographic picture.

AIM

To verify the impact of this methodology on the detection of biliary sludge in patients with 'idiopathic' pancreatitis.

METHODS

Fifty patients with 'idiopathic' pancreatitis observed over a 18-month period entered the study. Exclusion criteria were gall-bladder stones, polyps, clinical conditions related to biliary sludge development and haemolytic disorders. Patients were assessed blind by two operators using either conventional ultrasonography or second harmonic imaging. The parameters of diagnostic quality of both examinations were evaluated using, as the gold standard, microscopic examination of the gall-bladder content collected at endoscopy after cholecystokinin infusion.

RESULTS

An improvement in sensitivity, specificity, efficiency and negative predictive value was obtained by second harmonic imaging compared with conventional ultrasonography.

CONCLUSIONS

Second harmonic imaging, in our experience, is a reliable non-invasive tool for the diagnosis and follow-up of biliary sludge in the course of 'idiopathic' pancreatitis.

Helicobacter heilmannii gastritis: a histological and immunohistochemical trait

AIM

Biopsies of the gastric antrum were reviewed over a period of 10 years to determine the prevalence of Helicobacter heilmannii in symptomatic subjects from this geographical area and to relate its presence to distinctive histopathological and immunohistochemical features.

METHODS

Biopsies from 7926 symptomatic patients were reviewed. Ten serial sections were stained with haematoxylin and eosin for conventional histology. Another 10 sections were stained with the Gram method for spiral bacteria. When H heilmannii was suspected, 10 additional serial sections were stained with methylene blue to obtain homogeneous colouring. An equal number of sections from patients affected by isolated H heilmannii or H pylori gastritis were analysed by immunohistochemistry to evaluate lymphoid aggregate/mucosal lymphocyte clonality (CD20 and CD3) and tumour necrosis factor alpha (TNF-alpha) in stromal cells.

RESULTS

The prevalence of H heilmannii was 0.1% (eight of 7926), whereas H pylori was present in 60.7% of patients (4813 of 7926). In two of the eight H heilmannii positive patients both helicobacters were found. In all subjects infected by H heilmannii only, distinctive histology (lymphocyte exudation into gastric foveolae) was seen. Lymphoid aggregates, chronic mucosal inflammation with patchy activity, and the absence of epithelial mucus depletion were regular features of H heilmannii gastritis. Immunohistochemistry did not reveal different lymphocyte clonal patterns between H pylori and H heilmannii gastritis: CD20 positive cells were predominant in the centre of aggregates and mucosal infiltrates, whereas CD3 positive cells were prevalent at the periphery of follicles. Only H pylori gastritis showed a significant increase in TNF-alpha positive stromal cells.

CONCLUSION

These data suggest that an unusual lymphocyte reaction, with the tendency to invade the foveolar lumen, is a distinctive histopathological aspect of H heilmannii chronic gastritis, although further studies in a larger series are necessary to confirm this fact. Nevertheless, lymphocyte clones do not differ qualitatively from those found in H pylori infection. Moreover, compared with H heilmannii, H pylori provokes a more intense release of TNF-alpha, suggesting that different inflammatory responses exist to these two organisms.