Rapid urease tests lack sensitivity in Helicobacter pylori diagnosis when peptic ulcer disease presents with bleeding

Accuracy of gastric nodule combined with rapid urease test prediction in diagnosing Helicobacter pylori infection in children

BACKGROUND

The diagnosis of Helicobacter pylori (H. pylori) infection in children remains challenging with the lack of a rapid, cost-effective, and highly accurate diagnostic method. Consequently, this study aimed to investigate the accuracy of the combination of gastric nodule and rapid urease test (RUT) as a diagnostic method for H. pylori infection in children.

METHODS

The study included participants who underwent a thorough examination, including gastroscopy, a 13C breath test, RUT, and pathological methylene blue staining, with the gold standard for diagnosing of H. pylori infection being a positive result from both pathological methylene blue staining and 13C breath test. The sensitivity, specificity, positive and negative predictive values, and accuracy of the diagnostic methods were calculated.

RESULTS

The accuracy of the different tests for H. pylori infection was evaluated in 2202 participants. A total of 730 (33.2%) children were diagnosed with H. pylori infection (pathological methylene blue staining and 13C breath test, both positive). Gastric nodule had a sensitivity of 87.1% and a specificity of 93.1%, whereas combining gastric nodule and RUT in parallel had the higher accuracy of 95.4%. The accuracy of gastric nodule diagnosis was higher in younger age groups and increased after excluding patients with a history of anti-H. pylori treatment.

CONCLUSIONS

The findings of this study suggest that gastric nodules, particularly when combined with RUT, can be a valuable predictor of H. pylori infection in children, offering a simple and feasible alternative to other invasive methods.

Application of artificial intelligence in endoscopic image analysis for the diagnosis of a gastric cancer pathogen-Helicobacter pylori infection

Helicobacter pylori (H. pylori) infection is the principal cause of chronic gastritis, gastric ulcers, duodenal ulcers, and gastric cancer. In clinical practice, diagnosis of H. pylori infection by a gastroenterologists' impression of endoscopic images is inaccurate and cannot be used for the management of gastrointestinal diseases. The aim of this study was to develop an artificial intelligence classification system for the diagnosis of H. pylori infection by pre-processing endoscopic images and machine learning methods. Endoscopic images of the gastric body and antrum from 302 patients receiving endoscopy with confirmation of H. pylori status by a rapid urease test at An Nan Hospital were obtained for the derivation and validation of an artificial intelligence classification system. The H. pylori status was interpreted as positive or negative by Convolutional Neural Network (CNN) and Concurrent Spatial and Channel Squeeze and Excitation (scSE) network, combined with different classification models for deep learning of gastric images. The comprehensive assessment for H. pylori status by scSE-CatBoost classification models for both body and antrum images from same patients achieved an accuracy of 0.90, sensitivity of 1.00, specificity of 0.81, positive predictive value of 0.82, negative predicted value of 1.00, and area under the curve of 0.88. The data suggest that an artificial intelligence classification model using scSE-CatBoost deep learning for gastric endoscopic images can distinguish H. pylori status with good performance and is useful for the survey or diagnosis of H. pylori infection in clinical practice.

Helicobacter pylori Infection, Its Laboratory Diagnosis, and Antimicrobial Resistance: a Perspective of Clinical Relevance

Despite the recent decrease in overall prevalence of Helicobacter pylori infection, morbidity and mortality rates associated with gastric cancer remain high. The antimicrobial resistance developments and treatment failure are fueling the global burden of H. pylori-associated gastric complications. Accurate diagnosis remains the opening move for treatment and eradication of infections caused by microorganisms. Although several reports have been published on diagnostic approaches for H. pylori infection, most lack the data regarding diagnosis from a clinical perspective. Therefore, we provide an intensive, comprehensive, and updated description of the currently available diagnostic methods that can help clinicians, infection diagnosis professionals, and H. pylori researchers working on infection epidemiology to broaden their understanding and to select appropriate diagnostic methods. We also emphasize appropriate diagnostic approaches based on clinical settings (either clinical diagnosis or mass screening), patient factors (either age or other predisposing factors), and clinical factors (either upper gastrointestinal bleeding or partial gastrectomy) and appropriate methods to be considered for evaluating eradication efficacy. Furthermore, to cope with the increasing trend of antimicrobial resistance, a better understanding of its emergence and current diagnostic approaches for resistance detection remain inevitable.

Accuracy of the Helicobacter pylori diagnostic tests in patients with peptic ulcer bleeding: a systematic review and network meta-analysis

INTRODUCTION

Some studies suggest that the accuracy of Helicobacter pylori diagnostic tests is decreased in peptic ulcer bleeding (PUB). We aimed to assess the accuracy of diagnostic tests for H. pylori in patients with PUB in a diagnostic test accuracy (DTA) network meta-analysis.

METHODS

A systematic search was carried out in seven databases until November 2019. We collected or calculated true and false positive and negative values, and constructed 2×2 diagnostic contingency tables with reference standards including histology, rapid urease test, urea breath test, serology, stool antigen test, culture, and polymerase chain reaction. We ranked the index tests by the superiority indices (SI) and calculated pooled sensitivity and specificity of each test.

DISCUSSION

Our search yielded 40 eligible studies with 27 different diagnostic strategies for H. pylori. In 32 articles, the reference standard was a combination of multiple tests. In 12 studies, the index tests were compared with a single testing method. We analyzed seven networks with the reference standards against a single or a combination of diagnostic index tests. None of the index tests had better diagnostic accuracy (SI between 9.94 and 2.17) compared with the individual index tests as all the confidence intervals included 1. Combined testing strategies had higher sensitivities (0.92-0.62) and lower specificities (0.85-0.46) while single tests proved to have higher specificities (0.83-0.77) and lower sensitivities (0.73-0.42).

CONCLUSION

Use of combined tests may have a rationale in clinical practice due to their higher sensitivities. The differences between the included DTA studies limited the comparison of the testing strategies.

Diagnostic accuracy of "sweeping" method compared to conventional sampling in rapid urease test for Helicobacter pylori detection in atrophic mucosa

Although the rapid urease test (RUT) is a simple method for detecting Helicobacter pylori (H. pylori) infection, it requires sufficient biopsy samples and its sensitivity varies depending on the site and condition of H. pylori infection. We compared the diagnostic performance of a “sweeping method” for H. pylori detection with the conventional biopsy sampling method in atrophic gastric conditions which can reduce RUT accuracy. This prospective study included 279 patients who underwent upper endoscopy to determine the presence of H. pylori infection. Gastric mucosa of both the antrum and the corpus were swabbed, and we named this method the “sweeping method”. Biopsy sampling for the conventional method, histologic evaluation, and polymerase chain reaction were performed at the same time. The sensitivity, specificity, and accuracy of the sweeping method were 0.941, 0.826, and 0.903, respectively, compared to 0.685, 0.859, and 0.742, respectively, for the conventional biopsy method. The area under the receiver operating curve for the sweeping method was 0.884 versus 0.772 for the conventional method (P < 0.001). The sweeping method had a faster detection time than the conventional method. Compared to conventional biopsy sampling, the sweeping method with the RUT provided higher sensitivity and accuracy for the detection of H. pylori, with a faster detection time.

Are Histopathological Changes of H. pylori Infection in Young Dyspeptic Patients Necessitate Endoscopy?

BACKGROUND:

Helicobacter pylori is an important gastrointestinal infective bacteria with many serious complications including gastric erosions and ulceration, duodenal ulcer, gastric carcinoma and MALT gastric lymphoma. The gastric biopsy is commonly performed in H. pylori-positive dyspeptic individuals, and many previous researchers studied the histopathological features of infected gastric biopsies however little previous studies focused on the histopathological findings in young population in comparison to the older one.

AIM:

To make a focus on the histopathological effects of H. pylori infection in young patients compared with the older one and predicts the need for endoscopy in this population, also to estimates the prevalence of infection in Iraqi patients.

MATERIAL AND METHODS:

the sample for this study is 180 patients in total, they attended Marjan medical city in Iraq for dyspepsia of more than 3 months and prepared for OGD. Patients asked for their permission to do immunological tests for H. pylori. Both serology for H. pylori antibodies and stool for antigen tests are used, and the case is included in the study only if both tests were positive, after OGD, the gastric biopsies are processed and examined histopathologically.

RESULTS:

Normal gastric biopsy is the most common histopathological finding in young (< 25 years) patients (75%) while chronic atrophic gastritis is the most common one in patients > 25 years age (57%). The prevalence of Helicobacter pylori infection in dyspeptic patients was 73.3%, the correlation between infection and sex was insignificant (p-value 0.06), and no significant correlation between infection and age (p-value 0.07) was concluded.

CONCLUSION:

H. pylori-related histopathological changes of gastric mucosa in young (< 25 years) are commonly mild and does not necessitate endoscopy at this age unless there are alarming signs.

Raman tracking the activity of urease in saliva for healthcare

The detection of urease activity in the oral cavity is considered to be an efficient way to prevent dental caries and also to screen for helicobacter pylori infection. Herein, a rapid surface enhanced Raman scattering (SERS) method is proposed to determine the activity of urease by using inositol hexaphosphate (IP₆) stabilized silver nanoparticles (AgNPs@IP₆) as an efficient SERS-active substrate. The determination was achieved by monitoring the SERS peak intensity of urea at 1003 cm^-1. With urease increase, the response of urea at 1003 cm^-1 decreases gradually, indicating the two has good correlation. A linear relationship between the absolute value of signal drop and urease concentration is observed in a range from 2.35 to 37.5 μg/mL. In addition, the rapid SERS method was used to evaluate the activity of urease in real sample of saliva without any pretreatment, exhibiting a promising potential for biomedical application.

IVTH BRAZILIAN CONSENSUS CONFERENCE ON HELICOBACTER PYLORI INFECTION

ABSTRACT Significant progress has been obtained since the III Brazilian Consensus Conference on H. pylori infection held in 2012, in Bento Gonçalves, Brazil, and justify a fourth meeting to establish updated guidelines on the current management of H. pylori infection. Therefore, the Núcleo Brasileiro para Estudo do Helicobacter pylori e Microbiota (NBEHPM), association linked to Brazilian Federation of Gastroenterology (FBG) held its fourth meeting again in Bento Gonçalves, RS, Brazil, on August 25-27, 2017. Twenty-six delegates, including gastroenterologists, endoscopists, and pathologists from the five regions of Brazil as well as one international guest from the United States, participated in the meeting. The participants were invited based on their knowledge and contribution to the study of H. pylori infection. The meeting sought to review different aspects of treatment for infection; establish a correlation between infection, dyspepsia, intestinal microbiota changes, and other disorders with a special emphasis on gastric cancer; and reassess the epidemiological and diagnostic aspects of H. pylori infection. Participants were allocated into four groups as follows: 1) Epidemiology and Diagnosis, 2) Dyspepsia, intestinal microbiota and other afections, 3) Gastric Cancer, and, 4) Treatment. Before the consensus meeting, participants received a topic to be discussed and prepared a document containing a recent literature review and statements that should be discussed and eventually modified during the face-to-face meeting. All statements were evaluated in two rounds of voting. Initially, each participant discussed the document and statements with his group for possible modifications and voting. Subsequently, during a second voting in a plenary session in the presence of all participants, the statements were voted upon and eventually modified. The participants could vote using five alternatives: 1) strongly agree; 2) partially agree; 3) undecided; 4) disagree; and 5) strongly disagree. The adopted consensus index was that 80% of the participants responded that they strongly or partially agreed with each statement. The recommendations reported are intended to provide the most current and relevant evidences to management of H. pylori infection in adult population in Brazil.

Non-invasive diagnostic tests for Helicobacter pylori infection

BACKGROUND

Helicobacter pylori (H pylori) infection has been implicated in a number of malignancies and non-malignant conditions including peptic ulcers, non-ulcer dyspepsia, recurrent peptic ulcer bleeding, unexplained iron deficiency anaemia, idiopathic thrombocytopaenia purpura, and colorectal adenomas. The confirmatory diagnosis of H pylori is by endoscopic biopsy, followed by histopathological examination using haemotoxylin and eosin (H & E) stain or special stains such as Giemsa stain and Warthin-Starry stain. Special stains are more accurate than H & E stain. There is significant uncertainty about the diagnostic accuracy of non-invasive tests for diagnosis of H pylori.

OBJECTIVES

To compare the diagnostic accuracy of urea breath test, serology, and stool antigen test, used alone or in combination, for diagnosis of H pylori infection in symptomatic and asymptomatic people, so that eradication therapy for H pylori can be started.

SEARCH METHODS

We searched MEDLINE, Embase, the Science Citation Index and the National Institute for Health Research Health Technology Assessment Database on 4 March 2016. We screened references in the included studies to identify additional studies. We also conducted citation searches of relevant studies, most recently on 4 December 2016. We did not restrict studies by language or publication status, or whether data were collected prospectively or retrospectively.

SELECTION CRITERIA

We included diagnostic accuracy studies that evaluated at least one of the index tests (urea breath test using isotopes such as 13C or 14C, serology and stool antigen test) against the reference standard (histopathological examination using H & E stain, special stains or immunohistochemical stain) in people suspected of having H pylori infection.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the references to identify relevant studies and independently extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We performed meta-analysis by using the hierarchical summary receiver operating characteristic (HSROC) model to estimate and compare SROC curves. Where appropriate, we used bivariate or univariate logistic regression models to estimate summary sensitivities and specificities.

MAIN RESULTS

We included 101 studies involving 11,003 participants, of which 5839 participants (53.1%) had H pylori infection. The prevalence of H pylori infection in the studies ranged from 15.2% to 94.7%, with a median prevalence of 53.7% (interquartile range 42.0% to 66.5%). Most of the studies (57%) included participants with dyspepsia and 53 studies excluded participants who recently had proton pump inhibitors or antibiotics.There was at least an unclear risk of bias or unclear applicability concern for each study.Of the 101 studies, 15 compared the accuracy of two index tests and two studies compared the accuracy of three index tests. Thirty-four studies (4242 participants) evaluated serology; 29 studies (2988 participants) evaluated stool antigen test; 34 studies (3139 participants) evaluated urea breath test-13C; 21 studies (1810 participants) evaluated urea breath test-14C; and two studies (127 participants) evaluated urea breath test but did not report the isotope used. The thresholds used to define test positivity and the staining techniques used for histopathological examination (reference standard) varied between studies. Due to sparse data for each threshold reported, it was not possible to identify the best threshold for each test.Using data from 99 studies in an indirect test comparison, there was statistical evidence of a difference in diagnostic accuracy between urea breath test-13C, urea breath test-14C, serology and stool antigen test (P = 0.024). The diagnostic odds ratios for urea breath test-13C, urea breath test-14C, serology, and stool antigen test were 153 (95% confidence interval (CI) 73.7 to 316), 105 (95% CI 74.0 to 150), 47.4 (95% CI 25.5 to 88.1) and 45.1 (95% CI 24.2 to 84.1). The sensitivity (95% CI) estimated at a fixed specificity of 0.90 (median from studies across the four tests), was 0.94 (95% CI 0.89 to 0.97) for urea breath test-13C, 0.92 (95% CI 0.89 to 0.94) for urea breath test-14C, 0.84 (95% CI 0.74 to 0.91) for serology, and 0.83 (95% CI 0.73 to 0.90) for stool antigen test. This implies that on average, given a specificity of 0.90 and prevalence of 53.7% (median specificity and prevalence in the studies), out of 1000 people tested for H pylori infection, there will be 46 false positives (people without H pylori infection who will be diagnosed as having H pylori infection). In this hypothetical cohort, urea breath test-13C, urea breath test-14C, serology, and stool antigen test will give 30 (95% CI 15 to 58), 42 (95% CI 30 to 58), 86 (95% CI 50 to 140), and 89 (95% CI 52 to 146) false negatives respectively (people with H pylori infection for whom the diagnosis of H pylori will be missed).Direct comparisons were based on few head-to-head studies. The ratios of diagnostic odds ratios (DORs) were 0.68 (95% CI 0.12 to 3.70; P = 0.56) for urea breath test-13C versus serology (seven studies), and 0.88 (95% CI 0.14 to 5.56; P = 0.84) for urea breath test-13C versus stool antigen test (seven studies). The 95% CIs of these estimates overlap with those of the ratios of DORs from the indirect comparison. Data were limited or unavailable for meta-analysis of other direct comparisons.

AUTHORS' CONCLUSIONS

In people without a history of gastrectomy and those who have not recently had antibiotics or proton ,pump inhibitors, urea breath tests had high diagnostic accuracy while serology and stool antigen tests were less accurate for diagnosis of Helicobacter pylori infection.This is based on an indirect test comparison (with potential for bias due to confounding), as evidence from direct comparisons was limited or unavailable. The thresholds used for these tests were highly variable and we were unable to identify specific thresholds that might be useful in clinical practice.We need further comparative studies of high methodological quality to obtain more reliable evidence of relative accuracy between the tests. Such studies should be conducted prospectively in a representative spectrum of participants and clearly reported to ensure low risk of bias. Most importantly, studies should prespecify and clearly report thresholds used, and should avoid inappropriate exclusions.

Utility of normalized genome quantification of Helicobacter pylori in gastric mucosa using an in-house real-time polymerase chain reaction

Traditional diagnostic assays for Helicobacter pylori detection have their limitations. Molecular methods can improve both diagnosis and understanding of gastric diseases. Here we describe an in-house quantitative real-time polymerase chain reaction (q-rt-PCR) for the detection of H. pylori in gastric biopsies which has been developed and has a detection limit of 10 copies, the specificity of which was tested against other gastric colonizer bacteria. In this study, 199 gastric biopsies from adults with different clinical gastric symptoms were examined. Biopsies were obtained during endoscopy and the following tests performed: rapid urease testing (RUT), culture and q-rt-PCR. H. pylori bacterial load expressed as bacterial load per 105 cells was calculated using a standard curve. H. pylori was isolated in 41% of patients, RUT was positive in 32% and bacterial genome was detected in 45% (p = 0.010). Concordance between traditional invasive microbiological methods used together and q-rt-PCR was almost 100%. Bacterial load in patients with positive RUT was significantly higher than those where it was negative (p<0.0001). There were also significant differences between bacterial load in patients with more than one positive assay versus those where only one method was positive (p = 0.006). The in-house q-PCR developed here is quick and inexpensive, and allows accurate diagnosis of H. pylori infection. It also permits normalized bacterial load quantification, which is important to differentiate between asymptomatic colonisation and infection.

Management of non variceal upper gastrointestinal bleeding: position statement of the Catalan Society of Gastroenterology

In recent years there have been advances in the management of non-variceal upper gastrointestinal bleeding that have helped reduce rebleeding and mortality. This document positioning of the Catalan Society of Digestologia is an update of evidence-based recommendations on management of gastrointestinal bleeding peptic ulcer.

Acid-reducing vagotomy is associated with reduced risk of subsequent ischemic heart disease in complicated peptic ulcer: An Asian population study

Persistent exacerbation of a peptic ulcer may lead to a complicated peptic ulcer (perforation or/and bleeding). The management of complicated peptic ulcers has shifted from acid-reducing vagotomy, drainage, and gastrectomy to simple local suture or non-operative (endoscopic/angiographic) hemostasis. We were interested in the long-term effects of this trend change. In this study, complicated peptic ulcer patients who received acid-reducing vagotomy were compared with those who received simple suture/hemostasis to determine the risk of ischemic heart disease (IHD).This retrospective cohort study analyzed 335,680 peptic ulcer patients recorded from 2000 to 2006 versus 335,680 age-, sex-, comorbidity-, and index-year matched comparisons. Patients with Helicobacter pylori (HP) infection were excluded. In order to identify the effect of vagus nerve severance, patients who received gastrectomy or antrectomy were also excluded. The incidence of IHD in both cohorts, and in the complicated peptic ulcer patients who received acid-reducing vagotomy versus those who received simple suture or hemostasis was evaluated.The overall incidence of IHD was higher in patients with peptic ulcer than those without peptic ulcer (17.00 vs 12.06 per 1000 person-years), with an adjusted hazard ratio (aHR) of 1.46 based on multivariable Cox proportional hazards regression analysis controlling for age, sex, Charlson's comorbidity index, and death (competing risk). While comparing peptic ulcer patients with acid-reducing vagotomy to those with simple suture/hemostasis or those without surgical treatment, the aHR (0.58) was the lowest in the acid-reducing vagotomy group.Patients with peptic ulcer have an elevated risk of IHD. However, complicated peptic ulcer patients who received acid-reducing vagotomy were associated with reduced risk of developing IHD.

Dual-priming oligonucleotide-based multiplex PCR using tissue samples from the rapid urease test kit for the detection of Helicobacter pylori in bleeding peptic ulcers

BACKGROUND

In patients with peptic ulcer bleeding (PUB), diagnostic tests for Helicobacter pylori (H. pylori) infection have low sensitivity. The aim of our study was to investigate the diagnostic yield of dual-priming oligonucleotide-based multiplex (DPO)-PCR using tissue samples from the rapid urease test (RUT, CLO(®)test) kit in patients with PUB.

METHODS

We prospectively enrolled patients with PUB. During second-look endoscopy, gastric biopsy specimens for histology and RUT were obtained from a total of 170 patients. DPO-PCR tests were performed on tissue samples obtained from the CLO(®)test kit. If testing for H. pylori was negative, endoscopy with re-biopsy was performed 8 weeks after the bleeding episode.

RESULTS

H. pylori-associated bleeding was confirmed in 64.1% (109/170) of the patients. At the bleeding episode, the diagnostic sensitivities of RUT, histology, and DPO-PCR test were 47.7% (52/109), 71.6% (78/109) and 97.2% (106/109), respectively (p<0.01). The specificity of the DPO-PCR test was 91.8% (56/61). The positive predictive value (PPV) of the DPO-PCR test was 95.5% (106/111), and its negative predictive value (NPV) was 94.9% (56/59).

CONCLUSIONS

In patients with PUB, the DPO-PCR test could be a useful diagnostic tool for H. pylori infection. Particularly given a negative RUT result, subsequent DPO-PCR testing of tissue samples from the CLO(®)test kit could be of considerable benefit.

Helicobacter pylori Eradication within 120 Days Is Associated with Decreased Complicated Recurrent Peptic Ulcers in Peptic Ulcer Bleeding Patients

Background/Aims

The connection between Helicobacter pylori and complicated peptic ulcer disease in peptic ulcer bleeding (PUB) patients taking nonsteroidal anti-inflammatory drugs has not been established. In this study, we sought to determine whether delayed H. pylori eradication therapy in PUB patients increases complicated recurrent peptic ulcers.

Methods

We identified inpatient PUB patients using the Taiwan National Health Insurance Research Database. We categorized patients into early (time lag ≤120 days after peptic ulcer diagnosis) and late H. pylori eradication therapy groups. The Cox proportional hazards model was used. The primary outcome was rehospitalization for patients with complicated recurrent peptic ulcers.

Results

Our data indicated that the late H. pylori eradication therapy group had a higher rate of complicated recurrent peptic ulcers (hazard ratio [HR], 1.52; p=0.006), with time lags of more than 120 days. However, our results indicated a similar risk of complicated recurrent peptic ulcers (HR, 1.20; p=0.275) in time lags of more than 1 year and (HR, 1.10; p=0.621) more than 2 years.

Conclusions

H. pylori eradication within 120 days was associated with decreased complicated recurrent peptic ulcers in patients with PUB. We recommend that H. pylori eradication should be conducted within 120 days in patients with PUB.

A systematic approach for the diagnosis and treatment of idiopathic peptic ulcers

An idiopathic peptic ulcer is defined as an ulcer with unknown cause or an ulcer that appears to arise spontaneously. The first step in treatment is to exclude common possible causes, including Helicobacter pylori infection, infection with other pathogens, ulcerogenic drugs, and uncommon diseases with upper gastrointestinal manifestations. When all known causes are excluded, a diagnosis of idiopathic peptic ulcer can be made. A patient whose peptic ulcer is idiopathic may have a higher risk for complicated ulcer disease, a poorer response to gastric acid suppressants, and a higher recurrence rate after treatment. Risk factors associated with this disease may include genetic predisposition, older age, chronic mesenteric ischemia, smoking, concomitant diseases, a higher American Society of Anesthesiologists score, and higher stress. Therefore, the diagnosis and management of emerging disease should systematically explore all known causes and treat underlying disease, while including regular endoscopic surveillance to confirm ulcer healing and the use of proton-pump inhibitors on a case-by-case basis.

Diagnosis of Helicobacter pylori: Changes towards the Future

Since the first evidence demonstrating the dramatically high incidence of H. pylori infection and the subsequent medical challenges it incurs, health management of H. pylori infection has been a high priority for health authorities worldwide. Despite a decreasing rate of infection in western countries, prevalence of H. pylori infection in developing and in some industrial countries is still very high. Whereas treatment and vaccination against H. pylori is a contemporary issue in medical communities, selective treatment and prior high-throughput screening of the subject population is a major concern of health organizations. So far, diagnostic tests are either elaborative and require relatively advanced medical care infrastructure or they do not fulfill the criteria recommended by the Maastricht IV/Florence consensus report. In this review, in light of recent scientific studies, we highlight current and possible future approaches for the diagnosis of H. pylori. We point out that novel non-invasive tests may not only cover the requirements of gold standard methods in H. pylori detection but also offer the potential for risk stratification of infection in a high throughput manner.

Increasing biopsy number and sampling from gastric body improve the sensitivity of rapid urease test in patients with peptic ulcer bleeding

BACKGROUND

Previous studies demonstrated that the sensitivity of rapid urease test (RUT) for diagnosis of Helicobacter pylori infection decreased during peptic ulcer bleeding.

AIM

We designed this study and tried to find a better method to improve the detection rate of H. pylori infection at the same session of endoscopic diagnosis of peptic ulcer bleeding.

METHODS

We prospectively enrolled 116 patients with peptic ulcer bleeding. These patients received intravenous proton pump inhibitor and then received upper gastrointestinal endoscopy within 24 h after arrival. We took one piece of biopsy from gastric antrum (Group 1), four pieces from gastric antrum (Group 2), and one piece from the gastric body (Group 3) for three separate RUTs, respectively. (13)C-urease breath test was used as gold standard for diagnosis of H. pylori infection.

RESULTS

There were 74 patients (64 %) with positive (13)C-urease breath test. Among these 74 patients, 45 patients had positive RUT (sensitivity: 61 %) in Group 1; 55 patients had positive RUT (sensitivity: 74 %) in Group 2; 54 patients had positive RUT (sensitivity: 73 %) in Group 3. There were significant differences between Group 1 and Group 2 (p = 0.02) and between Group 1 and Group 3 (p = 0.022).

CONCLUSIONS

The sensitivity of RUT was 61 % during peptic ulcer bleeding. The sensitivity of RUT can be increased significantly by increased biopsy number from gastric antrum or biopsy from gastric body.

Absence of Helicobacter pylori is not protective against peptic ulcer bleeding in elderly on offending agents: lessons from an exceptionally low prevalence population

Aim. Helicobacter pylori (H. pylori) infection is exceptionally rare in population from the north-eastern region of Peninsular Malaysia. This provides us an opportunity to contemplate the future without H. pylori in acute non-variceal upper gastrointestinal (GI) bleeding.

Methods. All cases in the GI registry with GI bleeding between 2003 and 2006 were reviewed. Cases with confirmed non-variceal aetiology were analysed. Rockall score > 5 was considered high risk for bleeding and primary outcomes studied were in-hospital mortality, recurrent bleeding and need for surgery.

Results. The incidence of non-variceal upper GI bleeding was 2.2/100,000 person-years. Peptic ulcer bleeding was the most common aetiology (1.8/100,000 person-years). In-hospital mortality (3.6%), recurrent bleeding (9.6%) and need for surgery (4.0%) were uncommon in this population with a largely low risk score (85.2% with score ≤5). Elderly were at greater risk for bleeding (mean 68.5 years, P = 0.01) especially in the presence of duodenal ulcers (P = 0.04) despite gastric ulcers being more common. NSAIDs, aspirin and co-morbidities were the main risk factors.

Conclusions. The absence of H. pylori infection may not reduce the risk of peptic ulcer bleeding in the presence of risk factors especially offending drugs in the elderly.

A new biphasic test for the detection of Helicobacter pylori in gastric biopsies

The objective of this study was to create a biphasic cultural method for the detection of Helicobacter pylori in gastric biopsy specimens. The biphasic systems were made by using a urea agar slant with overlaying broth in a single vessel. Initially, three different liquid media including brain-heart infusion broth, Brucella broth, and Bolton broth were tested for their ability to support the growth of H. pylori. Bolton broth with 10% defibrinated horse blood demonstrated a significant increase in the numbers of H. pylori (p<0.05). The result showed that positive urease was used to concentrate viable H. pylori cells where the numbers of bacteria were 10(5)cfu. In addition, the reliable incubation time was at least 36h. In total, 55 biopsies were comparatively studied using commercial rapid urease test and PCR. Seven samples (12.72%) were positive with H. pylori by the biphasic test. With the CLOtest, 6 (10.91%) samples were positive. In conclusion, the Hp biphasic test achieved more positive samples than did the commercial rapid urease test.

Real-time PCR for diagnosing Helicobacter pylori infection in patients with upper gastrointestinal bleeding: comparison with other classical diagnostic methods

The aim of this study was to determine the diagnostic usefulness of quantification of the H. pylori genome in detection of infection in patients with upper gastrointestinal bleeding (UGB). A total of 158 consecutive patients with digestive disorders, 80 of whom had clinical presentation of UGB, were studied. The number of microorganisms was quantified using a real-time PCR system which amplifies the urease gene with an internal control for eliminating the false negatives. A biopsy sample from the antrum and corpus of each patient was processed. The rapid urease test, culture, histological study, stool antigen test, and breath test were done. The gold standard was a positive culture or positive results in at least two of the other techniques. When a positive result was defined as any number of microorganisms/human cell, the sensitivity of real-time PCR was greater in bleeding patients, especially in the gastric corpus: 68.4% (95% confidence interval [CI], 52.3 to 84.5%) in non-UGB patients versus 91.5% (95% CI, 79.6 to 97.6%) in UGB patients. When a positive result was defined as a number of microorganisms/human cell above the optimal value that maximizes the Youden index (>3.56 microorganisms/human cell in the antrum and >2.69 in the corpus), the sensitivity and specificity in UGB patients were over 80% in both antrum and corpus. Our findings suggest that some bleeding patients with infection caused by H. pylori may not be correctly diagnosed by classical methods, and such patients could benefit from the improved diagnosis provided by real-time PCR. However, the clinical significance of a small number of microorganisms in patients with negative results in classical tests should be evaluated.

Evaluation of the effect of presence of blood in the stomach on endoscopic diagnostic tests for Helicobacter pylori infection

INTRODUCTION

Presence of blood in the stomach has been thought to affect the performance of diagnostic tests used in detecting Helicobacter pylori (H. pylori) in the stomach. This study evaluated the effect of blood on the efficacy of rapid urease test (RUT) and microscopic appearance of the biopsy after staining with Giemsa stain.

MATERIALS AND METHODS

Patients with bleeding oesophageal varices who met the inclusion criteria were tested for H. pylori by RUT and microscopic examination of the biopsy. A repeat endoscopy, RUT and histology were done one month following initial presentation. The performance of the diagnostic tests was evaluated with and without the presence of intraluminal blood. A combined result of the two tests, RUT and histology, carried out in presence or absence of blood for the diagnosis of H. pylori, when considered together was considered as the gold standard.

RESULTS

Thirty six patients included in the study were in the ages ranging between 15-60 years (mean age = 44.14 years ± 2.1). The combination of tests at both visits showed 20/36 (55.6%) patients were positive for H. pylori. The decrease in H. pylori positivity in the presence of blood was significant for RUT (8.3% vs. 38.9%; P=0.005) and combined test (19.4% vs. 47.2%; P=0.02) but the decrease in positivity for histology (11.1% vs 30.6%) was not significant (P=0.08). In the presence of blood, the sensitivity of RUT, histology and combined tests were 15%, 20% and 35%, respectively. In the absence of blood, the sensitivity of RUT, histology and combination of tests was 70%, 55% and 85%, respectively.

CONCLUSION

Blood in the stomach significantly decreased the sensitivity of RUT, histology and the combination of both. Negative results of these tests in acute upper gastro intestinal (GI) bleeding should therefore be interpreted carefully.

Ten-day sequential therapy is more effective than proton pump inhibitor-based therapy in Korea: a prospective, randomized study

BACKGROUND AND AIMS

The eradication rate of proton pump inhibitor (PPI)-based triple therapy for Helicobacter pylori (H. pylori) infection has decreased, mainly due to increasing antibiotic resistance, especially against clarithromycin. It has been reported that a 10-day sequential strategy can produce good outcomes. The aim of this prospective study was to assess the efficacy of sequential therapy as the first-line treatment for the eradication of H. pylori in Korea.

METHODS

A total of 116 patients with proven H. pylori infection received 10-day sequential therapy (20 mg rabeprazole and 1 g amoxicillin, twice daily for the first 5 days, followed by 20 mg rabeprazole, 500 mg clarithromycin, and 500 mg metronidazole, twice daily for the remaining 5 days); 130 patients received 7-day triple therapy (20 mg rabeprazole, 500 mg clarithromycin, and 1 g amoxicillin, twice daily for 7 days). Eradication was evaluated by the (13) C-urea breath test, 4 weeks after the completion of treatment. Compliance and adverse events were assessed.

RESULTS

The eradication rates of 10-day sequential therapy and PPI-based triple therapy were 79.3% (92/116) and 63% (82/130) by intention-to-treat analysis, respectively (P = 0.005), and 81.9% (91/111) and 64.5% (82/127) by per protocol analysis, respectively (P = 0.003). Mild adverse events occurred in both therapy groups (27.5% vs 23.8%), but both treatments were well tolerated.

CONCLUSION

The eradication rate of the 10-day sequential therapy regimen was significantly higher than that of PPI-based triple therapy in the Korean population. Ten-day sequential therapy might be effective as a first-line treatment for H. pylori infection in Korea.

Risk factors for peptic ulcer bleeding in terms of Helicobacter pylori, NSAIDs, and antiplatelet agents

OBJECTIVES

The role of the Helicobacter pylori, nonsteroidal anti-inflammatory drugs (NSAIDs), and antiplatelet agents in the risk of peptic ulcer bleeding has not yet been established. This study was performed to identify the risk factors for peptic ulcer bleeding compared with non-bleeding peptic ulcer disease (PUD).

MATERIAL AND METHODS

A total of 475 patients, 265 with bleeding PUD and 210 with non-bleeding PUD were consecutively recruited. H. pylori status was determined by histology, rapid urease test, and culture. Exposure to NSAIDs, aspirin, and antiplatelet agents (clopidogrel and ticlopidine) within 4 weeks was obtained.

RESULTS

Compared with non-bleeding PUD, bleeding PUD had a higher proportion of male gender and current smoking, alcohol drinking, history of aspirin/antiplatelet use, and history of PUD. Whereas the proportion of H. pylori infection and history of H. pylori eradication in bleeding PUD were significantly lower than that in non-bleeding PUD. In multivariate analysis, male gender (OR 1.78, 95% CI 1.10-2.89), drinking alcohol (OR 2.08, 95% CI 1.29-3.14), aspirin/antiplatelet use (OR 2.35, 95% CI 1.45-3.82), and history of PUD (OR 2.46, 95% CI 1.36-4.46) remained independent risk factors for bleeding PUD. When H. pylori status and aspirin/antiplatelet agent use were combined, highest risk of bleeding peptic ulcers was found among H. pylori-negative patients with a history of aspirin/antiplatelet agent use (OR 3.03 95% CI 1.48-6.18) compared with H. pylori-positive patients with no history of aspirin/antiplatelet agent use.

CONCLUSIONS

Patients with H. pylori-negative peptic ulcers who continuously took aspirin or antiplatelet agents had the highest peptic ulcer bleeding risk.

Quantitation of Helicobacter pylori ureC gene and its comparison with different diagnostic techniques and gastric histopathology

Numerous diagnostic assays for Helicobacter pylori detection are available. However, these techniques have their own advantages as well as limitations. Here we tried to develop a real-time quantitative (Q) PCR assay to measure ureC copy number to detect H. pylori, based on the fact that there is only one copy of the ureC gene per bacterium. We enrolled 120 adult patients [non-ulcer dyspepsia (NUD) 60, peptic ulcer disease (PUD) 20, gastric cancer (GC) 40] undergoing upper gastrointestinal endoscopies. During each endoscopic examination, antral biopsies from normal region of the antrum were obtained and subjected to the following tests: RUT, culture, histopathology, H. pylori-specific ureC PCR and ureC Q-PCR. Calculation of H. pylori copy number was based on the standard curve generated using 10-fold dilutions of DNA extracted from the H. pylori control strain varying from 10(5) to 10(1) copies. The prevalence of H. pylori infection in our study population was 54% with no significant difference among disease and control population. The sensitivity of Q-PCR was found to be 100% which was highest among all diagnostic tests. The established Q-PCR is around 10 times more sensitive than the conventional PCR method. The copy number of H. pylori DNA was significantly increased when overall gastritis, H. pylori density, chronic inflammation and intestinal metaplasia were present. In summary, we developed a rapid and sensitive Q-PCR method for detecting H. pylori. This technique offers a significant improvement over other available methods for detecting H. pylori in clinical and research samples.

Real-time PCR improves Helicobacter pylori detection in patients with peptic ulcer bleeding

BACKGROUND AND AIMS

Histological and rapid urease tests to detect H. pylori in biopsy specimens obtained during peptic ulcer bleeding episodes (PUB) often produce false-negative results. We aimed to examine whether immunohistochemistry and real-time PCR can improve the sensitivity of these biopsies.

PATIENTS AND METHODS

We selected 52 histology-negative formalin-fixed paraffin-embedded biopsy specimens obtained during PUB episodes. Additional tests showed 10 were true negatives and 42 were false negatives. We also selected 17 histology-positive biopsy specimens obtained during PUB to use as controls. We performed immunohistochemistry staining and real-time PCR for 16S rRNA, ureA, and 23S rRNA for H. pylori genes on all specimens.

RESULTS

All controls were positive for H. pylori on all PCR assays and immunohistochemical staining. Regarding the 52 initially negative biopsies, all PCR tests were significantly more sensitive than immunohistochemical staining (p<0.01). Sensitivity and specificity were 55% and 80% for 16S rRNA PCR, 43% and 90% for ureA PCR, 41% and 80% for 23S rRNA PCR, and 7% and 100% for immunohistochemical staining, respectively. Combined analysis of PCR assays for two genes were significantly more sensitive than ureA or 23S rRNA PCR tests alone (p<0.05) and marginally better than 16S rRNA PCR alone. The best combination was 16S rRNA+ureA, with a sensitivity of 64% and a specificity of 80%.

CONCLUSIONS

Real-time PCR improves the detection of H. pylori infection in histology-negative formalin-fixed paraffin-embedded biopsy samples obtained during PUB episodes. The low reported prevalence of H. pylori in PUB may be due to the failure of conventional tests to detect infection.

Advances in understanding relationship between Helicobacter pylori infection and peptic ulcer bleeding

Helicobacter pylori (H.pylori) is a definite causative factor for peptic ulcer; however, its role in peptic ulcer bleeding is not very clear. Detection of H.pylori infection in patients with peptic ulcer bleeding is often affected by methods and drugs used. H.pylori infection increases, to some extent, the risk of peptic ulcer bleeding. Eradication of H.pylori may reduce the risk of peptic ulcer bleeding and promote ulcer healing.

Has H. pylori prevalence in bleeding peptic ulcer been underestimated? A meta-regression

OBJECTIVES

It has been suggested that prevalence of Helicobacter pylori (Hp) in peptic ulcer bleeding (PUB) is lower than that in non-complicated ulcers. As Hp infection is elusive in PUB, we hypothesized that this low prevalence could be related to an insufficiently intensive search for the bacteria. The aim of the study was to evaluate whether the prevalence of Hp in PUB depends on the diagnostic methods used in a given study.

METHODS

A systematic review was performed of studies assessing the prevalence of Hp infection in patients with PUB. Data were extracted in duplicate. Univariate and multivariate random-effects meta-regression analyses were performed to determine the factors that explained the differences in Hp prevalence between studies.

RESULTS

The review retrieved 71 articles, including 8,496 patients. The mean prevalence of Hp infection in PUB was 72%. The meta-regression analysis showed that the most significant variables associated with a high prevalence of Hp infection were the use of a diagnostic test delayed until at least 4 weeks after the PUB episode-odds ratio: 2.08, 95% confidence interval: 1.10-3.93, P=0.024-and a lower mean age of patients-odds ratio: 0.95 per additional year, 95% confidence interval: 0.92-0.99, P=0.008.

CONCLUSIONS

Studies that performed a delayed test and those including younger patients found a higher prevalence of Hp, approaching that recorded in cases of non-bleeding ulcers. These results suggest that the low prevalence of Hp infection described in PUB may be related to the methodology of the studies and to patients' characteristics, and that the true prevalence of Hp in PUB is still to be determined. Our data also support the recent recommendations of the International Consensus on Non-Variceal Upper Gastrointestinal Bleeding regarding the performance of a delayed diagnostic test when Hp tests carried out during the acute PUB episode are negative.

Non-invasive testing for Helicobacter pylori in patients hospitalized with peptic ulcer hemorrhage: a cost-effectiveness analysis

PURPOSE

Guidelines recommend routine invasive screening for Helicobacter pylori in patients with peptic ulcer hemorrhage (PUH). However, compliance with screening remains suboptimal. The aim of this study was to determine if a simplified approach based on noninvasive screening is cost effective in PUH.

RESULTS

In the base case, post-endoscopy urea breath test (UBT) dominated the invasive testing with 34 fewer hemorrhages and cost savings of $406,600 in a cohort of 10,000 patients. When compliance with invasive testing decreases to 60%, post-endoscopy UBT leads to 109 fewer hemorrhages and cost savings of $1,089,600. The invasive strategy becomes the preferred choice if the sensitivity of UBT reduces to <75%, such as in patients taking proton-pump inhibitors (PPI) before hospitalization.

CONCLUSIONS

Post-endoscopy UBT is cost effective in PPI-naïve patients presenting with PUH. This strategy, once prospectively validated, can prove to be a preferred approach in institutions where compliance with invasive testing is suboptimal.

Review article: Helicobacter pylori-negative duodenal ulcer disease

BACKGROUND

Helicobacter pylori infection rates in duodenal ulcer (DU) patients may be lower than previously estimated.

AIM

To review the real prevalence of H. pylori-negative DUs and its possible causes.

METHODS

Bibliographical searches in MEDLINE looking for the terms 'H. pylori' and 'duodenal ulcer'.

RESULTS

Mean prevalence of H. pylori infection in DU disease, calculated from studies published during the last 10 years including a total of 16 080 patients, was 81%, and this figure was lower (77%) when only the last 5 years were considered. Associations with H. pylori-negative DU were: (1) False negative results of diagnostic methods, (2) NSAID use (21% in studies with <90% infection rate), (3) Complicated DU (bleeding, obstruction, perforation), (4) Smoking, (5) Isolated H. pylori duodenal colonization, (6) Older age, (7) Gastric hypersecretion, (8) Diseases of the duodenal mucosa, (9) Helicobacter'heilmanii' infection and (10) Concomitant diseases.

CONCLUSION

In patients with H. pylori-negative DU disease, one should carefully confirm that the assessment of H. pylori status is reliable. In truly H. pylori-negative patients, the most common single cause of DU is, by far, the use of NSAIDs. Ulcers not associated with H. pylori, NSAIDs or other obvious causes should, for the present, be viewed as 'idiopathic'. True idiopathic DU disease only exceptionally exists.

Progress in detection of gastric Helicobacter pylori infection

Precise tests or methods are the key points to improve diagnosis of Helicobacter pylori (H pylori) infection and to evaluate clinical therapeutic effect. According to the sampling location, these methods can be classified as: 1) those sampling from stomach, including morphological examination, bacterial culture, urease-dependent assays; and 2) other approaches, including serum test, gene analysis, H pylori stool antigen (H pylori-SA) detection, urine or saliva H pylori antibody detection, etc. This article reviews these methods systematically.

Risk factors involved in patients with bleeding peptic ulcers: a case-control study

Our objectives were to (1) identify the risk factors involved in patients with peptic ulcer disease and determine if they predict bleeding in these patients, (2) determine the association between these risk factors, and (3) analyze the cost effectiveness of various tests for Helicobacter pylori (H. pylori). Two-hundred and thirty patients were included in our study between January 2004 and June 2005 (128 bleeding peptic ulcer disease patients constituted the cases, 102 nonbleeding ulcer patients constituted the controls). H. pylori infection was assessed by urease test and biopsy from gastric antrum. There was no statistically significant difference between these groups regarding sex, age, or location of ulcer. Nonsteroidal anti-inflammatory drug (NSAID) use was higher in the case group (P < 0.001), and the rate of H. pylori infection was lower in these patients (P < 0.05). There was no interaction between NSAID use and H. pylori infection in predicting bleeding ulcer risk (P = 0.08). Sensitivity and specificity for urease test in detecting H. pylori was 75% and 99.7%, respectively. So a positive urease test does not need confirmation with biopsy, which is cost effective.

Non-variceal upper GI bleeding in patients already hospitalized for another condition

OBJECTIVES

To compare outpatients (OPs) presenting with non-variceal upper gastrointestinal bleeding (NVUGIB) to those who started hemorrhaging while in a hospital (inpatients, IPs) in a contemporary setting and to better identify predictors of outcome.

METHODS

Retrospective data from the Canadian Registry of Patients With Upper Gastrointestinal Bleeding Undergoing Endoscopy (RUGBE). Descriptive, inferential, and multivariate logistic regression models were carried out in 469 IPs (68.5+/-14 years, 36% women) and 1,395 OPs (65.5+/-18 years, 39% women) in 18 Canadian community and tertiary care centers.

RESULTS

Main outcomes were rebleeding, mortality, and their predictors. IPs differed from OPs in disease acuity (P=0.02) and comorbidities (3.1+/-1.7 vs. 2.3+/-1.5, P<0.001), and were admitted longer (7.2+/-7.4 vs. 5+/-5.4 days, P<0.001) and more often to intensive care unit (ICU; 40.5% vs. 16%, P<0.001). Ulcers or erosions predominated (83% vs. 85%, P=0.28), treated by endotherapy (38% vs. 36%, P=0.46). More IPs received proton pump inhibitors (PPIs; 88% vs. 83%, P=0.009). Mortality was greater for IPs (11% vs. 3.5%, P<0.001), but rebleeding (15.7% vs. 13.4%, P=0.23) and surgery (6.9% vs. 6.4%, P=0.72) were not. Among IPs, comorbidity (odds ratio, OR=1.15; 95% confidence interval, CI: 1.01-1.32) and endoscopic high-risk stigmata increased (OR=3.86, 95% CI:2.05-7.26), whereas PPI decreased (OR=0.20, 95% CI:0.10-0.42) rebleeding; high-risk stigmata (OR=3.13, 95% CI:1.23-7.99) and rebleeding (OR=4.19, 95% CI:2.06-8.55) increased mortality, whereas low disease acuity was protective (OR=0.20; 95% CI:0.46-0.90).

CONCLUSIONS

IPs are sicker than OPs. Endoscopic hemostasis and PPI therapy favorably affect rebleeding in IPs, whereas patient characteristics principally determine the threefold greater IPs mortality.

Endoscopic diagnosis of Helicobacter pylori infection by rapid urease test in bleeding peptic ulcers: a prospective case-control study

GOAL

To assess the efficacy of rapid urease test (RUT) in patients with bleeding ulcers, as well as the effects of visible blood in the stomach and short-term (<24 h) use of standard-dose proton pump inhibitor (PPI) on RUT sensitivity.

BACKGROUND

The sensitivity of RUT in the diagnosis of Helicobacter pylori in upper gastrointestinal bleeding has been reported with conflicting results.

STUDY

This was a prospective case-control study evaluating 324 consecutive patients with bleeding peptic ulcers (study group) and 164 with uncomplicated ulcers (control group). The presence of H. pylori infection was determined by both RUT and histology. Prevalence of H. pylori infection and the RUT sensitivity in diagnosing the bacteria between study and control groups were conducted.

RESULTS

The prevalence of H. pylori infection in those with bleeding ulcers was significantly lower than that of controls (53.7% vs. 65.2%, P=0.015). The false-negative rate of RUT in the study group was significantly greater than that of the control group (16.7% vs. 5.6%, P=0.006), whereas the sensitivity rates in the study group with or without gastric blood were significantly lower than those of the controls (79.6% vs. 94.4%, P=0.005; 84.8% vs. 94.4%, P=0.019). There was no significant difference in RUT sensitivity between study group with or without visible gastric blood (P=0.41). The RUT sensitivity rate was also not significantly different between those treated with PPI and those without in patients with bleeding ulcers (82.7% vs. 85.7%, P=0.67).

CONCLUSIONS

This study shows that the sensitivity of RUT in patients with bleeding ulcers is reduced. The presence of blood in the stomach and the short-term use of standard-dose PPI do not affect the RUT sensitivity in bleeding ulcers.

Outcomes of bleeding peptic ulcers: a prospective study

BACKGROUND AND AIM

Bleeding peptic ulcers can be due to Helicobacter pylori (H. pylori) infection, use of non-steroidal anti-inflammatory drugs (NSAIDs), or idiopathic causes. The aim of this prospective study was to identify the clinical outcomes of bleeding peptic ulcers related to different causes.

METHODS

A total of 390 patients with bleeding ulcers were evaluated consecutively between June 2005 and August 2006. The diagnosis of H. pylori infection was made at index endoscopy, using histology and the rapid urease test. If both endoscopic diagnostic tests were not performed, a serological test was applied to detect the presence of H. pylori infection in a previously untreated patient. The prevalence and outcome of bleeding ulcers are related to H. pylori infection, NSAID use, and non-H. pylori idiopathic causes. The outcome between patients who were admitted for ulcer bleeding (outpatient bleeder) and those who bled while hospitalized (in-hospital bleeder) was also compared.

RESULTS

NSAID ulcers were noted in 223 patients, H. pylori ulcers in 102, and non-H. pylori idiopathic ulcers in 65. In total, 298 patients had outpatient bleeders, and 92 had in-hospital bleeders. The overall 3-day rebleeding rate was 11.8% and the mortality rate was 5.4%. Eighteen of the 21 mortality cases died of their underlying comorbid illness. Patients with non-H. pylori idiopathic ulcers had a significantly higher mortality rate than NSAID and H. pylori ulcers (12.3% vs 4.5% vs 2.9%, P = 0.02). Patients with H. pylori ulcers had significantly favorable outcomes than patients with NSAID ulcers (less blood transfusion and a shorter hospital stay) and non-H. pylori idiopathic ulcers (shorter hospital stay and a lower mortality). Patients with in-hospital bleeders had an adverse outcome as compared to outpatient bleeders, including a 3-day rebleeding rate (25.0% vs 7.7%, P < 0.0001), 30-day rebleeding rate (32.6% vs 12.1%, P < 0.0001), and higher mortality rate (16.3% vs 2.0%, P < 0.0001).

CONCLUSION

This study emphasizes the role of non-H. pylori idiopathic ulcers and in-hospital bleeders as the determining high-risk predictors for bleeding peptic ulcers.

Epidemiology of acute upper gastrointestinal bleeding

Acute upper gastrointestinal bleeding is an important emergency situation. Population-based epidemiology data are important to get insight in the actual healthcare problem. There are only few recent epidemiological surveys regarding acute upper gastrointestinal bleeding. Several surveys focusing on peptic ulcer disease showed a significant decrease in admission and mortality of peptic ulcer disease. Several more recent epidemiological surveys show a decrease in incidence of all cause upper gastrointestinal bleeding. The incidence of peptic ulcer bleeding remained stable. Peptic ulcer bleeding is the most common cause of upper gastrointestinal bleeding, responsible for about 50% of all cases, followed by oesophagitis and erosive disease. Variceal bleeding is the cause of bleeding in cirrhotic patients in 50-60%. Rebleeding in upper gastrointestinal bleeding occurs in 7-16%, despite endoscopic therapy. Rebleeding is especially high in variceal bleeding and peptic ulcer bleeding. Mortality ranges between 3 and 14% and did not change in the past 10 years. Mortality is increasing with increasing age and is significantly higher in patients who are already admitted in hospital for co-morbidity. Risk factors for peptic ulcer bleeding are NSAIDs use and H. pylori infection. In patients at risk for gastrointestinal bleeding and using NSAIDs, a protective drug was only used in 10%. COX-2 selective inhibitors do cause less gastroduodenal ulcers compared to non-selective NSAIDs, however, more cardiovascular adverse events are reported. H. pylori infection is found in about 50% of peptic ulcer bleeding patients. H. pylori should be tested for in all ulcer patients and eradication should be given.

American College of Gastroenterology guideline on the management of Helicobacter pylori infection

Helicobacter pylori (H. pylori) remains a prevalent, worldwide, chronic infection. Though the prevalence of this infection appears to be decreasing in many parts of the world, H. pylori remains an important factor linked to the development of peptic ulcer disease, gastric malignanc and dyspeptic symptoms. Whether to test for H. pylori in patients with functional dyspepsia, gastroesophageal reflux disease (GERD), patients taking nonsteroidal antiinflammatory drugs, with iron deficiency anemia, or who are at greater risk of developing gastric cancer remains controversial. H. pylori can be diagnosed by endoscopic or nonendoscopic methods. A variety of factors including the need for endoscopy, pretest probability of infection, local availability, and an understanding of the performance characteristics and cost of the individual tests influences choice of evaluation in a given patient. Testing to prove eradication should be performed in patients who receive treatment of H. pylori for peptic ulcer disease, individuals with persistent dyspeptic symptoms despite the test-and-treat strategy, those with H. pylori-associated MALT lymphoma, and individuals who have undergone resection of early gastric cancer. Recent studies suggest that eradication rates achieved by first-line treatment with a proton pump inhibitor (PPI), clarithromycin, and amoxicillin have decreased to 70-85%, in part due to increasing clarithromycin resistance. Eradication rates may also be lower with 7 versus 14-day regimens. Bismuth-containing quadruple regimens for 7-14 days are another first-line treatment option. Sequential therapy for 10 days has shown promise in Europe but requires validation in North America. The most commonly used salvage regimen in patients with persistent H. pylori is bismuth quadruple therapy. Recent data suggest that a PPI, levofloxacin, and amoxicillin for 10 days is more effective and better tolerated than bismuth quadruple therapy for persistent H. pylori infection, though this needs to be validated in the United States.

ENDOSCOPIC MANAGEMENT OF NON-VARICEAL UPPER GASTROINTESTINAL HAEMORRHAGE

Endoscopy plays a central role in the diagnosis and treatment of non-variceal upper gastrointestinal haemorrhage. Advances in endoscopic techniques, supported by an increasing body of high quality data, have rendered endoscopy the first-line diagnostic and therapeutic intervention for the patient presenting with an upper gastrointestinal haemorrhage. However, endoscopic intervention must be considered in the context of the overall management of the bleeding patient, often with significant comorbidities. Although parameters such as hospitalization duration, transfusion requirements and surgery rates have improved with advances in endoscopic therapy, mortality rates remain relatively static. This review addresses the current status of endoscopic intervention for non-variceal upper gastrointestinal haemorrhage. Additionally, an overview of important periprocedural management issues is presented.

Management der Ulkusblutung

Bleeding peptic ulcers are responsible for about half of all upper gastrointestinal hemorrhages, one of the most frequent gastroenterological emergencies. In its pathogenesis, infection with Helicobacter pylori and the use of ulcerogenic drugs play a dominant role. Endoscopy has to be performed urgently when a decline in hemoglobin and/or hemodynamic instability occurs. The indications for local endoscopic therapy depend on the Forrest criteria, which include bleeding and the presence or absence of a blood clot or visible vessel. Local endoscopic therapy comprises injections and mechanical or thermal procedures. The efficacy of these procedures has been demonstrated. Additionally, proton pump inhibitors are administered. The prognosis for bleeding ulcers depends on the endoscopic findings as well as the age and comorbidity of the patients.

Accuracy of Helicobacter pylori diagnostic tests in patients with bleeding peptic ulcer: a systematic review and meta-analysis

OBJECTIVE

To perform a systematic review and a meta-analysis of diagnostic accuracy of the different tests aimed to detect Helicobacter pylori infection in patients with upper gastrointestinal bleeding (UGIB).

SELECTION OF STUDIES

assessing the accuracy of H. pylori diagnostic methods in patients with UGIB.

SEARCH STRATEGY

electronic bibliographical searches.

DATA EXTRACTION

independently done by two reviewers.

DATA SYNTHESIS

meta-analyses of the different tests were performed combining the sensitivities, specificities, and likelihood ratios (LRs) of the individual studies.

RESULTS

Studies showed a high degree of heterogeneity. Pooled sensitivity, specificity, LR+ and LR- (95% confidence interval (CI)) for the different methods were: Rapid urease test (16 studies/1,417 patients): 0.67 (0.64-0.70), 0.93 (0.90-0.96), 9.6 (5.1-18.1), and 0.31 (0.22-0.44). Histology (10 studies/827 patients): 0.70 (0.66-0.74), 0.90 (0.85-0.94), 6.7 (2.5-18.4), and 0.23 (0.12-0.46). Culture (3 studies/314 patients): 0.45 (0.39-0.51), 0.98 (0.92-1.00), 19.6 (4-96), and 0.31 (0.05-1.9). Urea breath test (8 studies/520 patients): 0.93 (0.90-0.95), 0.92 (0.87-0.96), 9.5 (3.9-23.3), and 0.11 (0.07-0.16). Stool antigen test (6 studies/377 patients): 0.87 (0.82-0.91), 0.70 (0.62-0.78), 2.3 (1.4-4), and 0.2 (0.13-0.3). Serology (9 studies/803 patients): 0.88 (0.85-0.90), 0.69 (0.62-0.75), 2.5 (1.6-4.1), and 0.25 (0.19-0.33).

CONCLUSION

Biopsy-based methods, such as rapid urease test, histology, and culture, have a low sensitivity, but a high specificity, in patients with UGIB. The accuracy of 13C-urea breath test remains very high in these patients. Stool antigen test is less accurate in UGIB. Although serology seems not to be influenced by UGIB, it cannot be recommended as the first diagnostic test for H. pylori infection in this setting.

Usefulness of a delayed test for the diagnosis of Helicobacter pylori infection in bleeding peptic ulcer

AIM

To evaluate (i) the diagnostic usefulness of a delayed test in initially negative patients; and (ii) the reliability of the rapid urease test, histology or a combination of the two to diagnose Helicobacter pylori during emergency endoscopy in a large clinical practice series.

PATIENTS AND METHODS

Records of patients with ulcer bleeding from 1995 to 2000 were reviewed. Patients with initially negative tests were retested 4-8 weeks after the bleeding episode. Sensitivity of urease, histology or a combination of the two to detect H. pylori at initial endoscopy and the efficacy of delayed Urea Breath Test in detecting missed infection was determined.

RESULTS

The study included 429 patients. A delayed second test detected H. pylori infection in 57 out of 72 (79%) of initially negative patients. The sensitivity for detecting H. pylori was 76%, 78% and 86% for urease, histology and their combination, respectively. The prevalence of H. pylori was 95% in duodenal and 88% in gastric ulcer. In addition, only one test was performed in 17 of the 32 patients who were considered negative.

CONCLUSION

Not even the combination of a negative urease and histology in the initial endoscopy is able to rule out infection in bleeding ulcer patients. A delayed test should be performed to rule out Helicobacter pylori infection completely.

Role of Helicobacter pylori infection and nonsteroidal anti-inflammatory drug use in bleeding peptic ulcers in Japan

BACKGROUND

Helicobacter pylori infection and nonsteroidal anti-inflammatory drugs (NSAIDs) are well-known major causes of peptic ulcers. This study aimed to characterize the features of bleeding peptic ulcers in Japan.

METHODS

This prospective study evaluated 116 patients revealed to have bleeding peptic ulcers from January 2000 to December 2002.

RESULTS

Eighty-eight of the 116 patients (75.9%) had H. pylori infection. Seventy (60.3%) patients were positive for H. pylori with no history of NSAID use (group A), and 18 (15.5%) were positive for H. pylori with a history of NSAID use (group B). Among the H. pylori-negative patients, 15 (12.9%) were associated with NSAID use (group C). Thirteen (11.2%) patients had no H. pylori infection or history of NSAID use (group D). Among the 33 patients with a history of NSAID use, 11 were on-demand NSAID users and 14 took daily low-dose aspirin. The patients in groups B and C were significantly older that those in groups A and D, and they more frequently had coexisting diseases compared with group A. In group D, 11 patients had atrophic changes revealed by endoscopic examination, suggesting a past H. pylori infection, and these atrophic changes remained at the time of bleeding. Many of the patients in group D had serious comorbidity. Compared with healthy control subjects, the concentrations of both phosphatidylcholine and phosphatidylethanolamine were significantly decreased in the antral gastric mucosa in all patient groups.

CONCLUSIONS

NSAID use contributed to bleeding ulcers in 28.4% of patients; thus, low-dose aspirin or on-demand NSAID use may cause bleeding ulcers. There were only two (1.7%) confirmed cases of H. pylori-negative, non-NSAID ulcers.

Diagnostic Utility of Invasive Tests and Serology for the Diagnosis of Helicobacter pylori Infection in Different Clinical Presentations

BACKGROUND

Invasive and noninvasive tests are used for the diagnosis of Helicobacter pylori infection. The aim of this study was to determine the diagnostic utility of rapid urease test (RUT), culture, histology and serology for the diagnosis of H. pylori in patients with different clinical presentations.

METHODS

We studied 527 consecutive patients (mean age, 52.5 years; F:M, 1.3; age range 15-89 years) enrolled at the Hospital Universitario, Universidad Autónoma de Nuevo León. Patients had gastric cancer (GC, 9.1%), non-ulcer dyspepsia (NUD, 81.4%), or peptic ulcer disease (PUD, 9.1%). The infection by H. pylori was determined by histology, rapid urease test, culture, and serology. Patients were determined as infected with H. pylori if at least a) two invasive tests were positive and b) two tests were positive (invasive or non-invasive). Diagnostic utility was calculated for each assay.

RESULTS

Prevalence of infection in the whole studied population was 50.9%. In NUD patients the prevalence was 51.3%, in PUD patients 58.3%, and in GC patients 39.6%. When we used the first diagnostic criteria, for the whole studied population, the RUT was the most reliable test, followed by the culture. Histology had the best sensitivity for the whole studied population and NUD patients and RUT had the best sensitivity value for the GC patients. In the whole studied population, NUD and GC patients, RUT and culture had the best specificity, accuracy and PPV. For PUD patients, serology had the best performance. When we used the second diagnostic criteria, histology and serology had a better performance compared with the results obtained with the first diagnostic criteria.

CONCLUSIONS

Diagnostic utility of the tests varies according to the clinical presentations, which should be considered in the selection of the diagnostic test for the detection of H. pylori.

The effect of GI bleeding on Helicobacter pylori diagnostic testing: a prospective study at the time of bleeding and 1 month later

BACKGROUND

Some case series and cohort studies suggest that acute GI bleeding decreases the sensitivity of Helicobacter pylori diagnostic testing.

OBJECTIVE

To assess H pylori biopsy testing in patients with acute upper-GI bleeding and 1 month later.

DESIGN

Prospective cohort study using patients as their own controls.

SETTING

Urban county hospital.

PATIENTS

Sixty-one patients with acute variceal bleeding.

INTERVENTIONS

Antral and body endoscopic biopsies at admission and 1 month later.

MAIN OUTCOME MEASUREMENTS

CLOtest and histologic examinations were performed and biopsy specimens were coded and mixed for blinded histologic examination for H pylori density and inflammation.

RESULTS

CLOtest results changed from H pylori negative at baseline to H pylori positive at 1 month in two patients (3%), from H pylori positive to H pylori negative in 6 patients (10%), and remained the same in 53 (87%). Histologic results changed from H pylori negative at baseline to H pylori positive at 1 month in two patients (3%), from H pylori positive to H pylori negative in 5 patients (8%), and remained the same in 54 (89%). Changes occurred only in patients with low H pylori density. No significant increase in H pylori density or change in inflammatory cell infiltration was seen. CLOtest sensitivity was 8% higher with bleeding vs. 1 month after bleeding (79% vs. 71%; 95% CI of difference was -11% to 27%; i.e., maximal potential decrease in sensitivity with bleeding is 11%).

LIMITATIONS

The population is not one for which H pylori testing is recommended, and biopsy test performance was less consistent than expected.

CONCLUSIONS

Acute-GI bleeding did not decrease the sensitivity of rapid urease testing, unless the effect lasts more than 1 month. Furthermore, bleeding did not produce falsely negative histologic examinations for H pylori, decrease H pylori density, or alter inflammatory cell infiltration. However, given the lower than expected overall CLOtest sensitivity and frequent use of proton pump inhibitors for GI bleeding, histology may be preferred in this setting.

Polymerase chain reaction: A sensitive method for detecting Helicobacter pylori infection in bleeding peptic ulcers

AIM: To assess the sensitivity and specificity of polymerase chain reaction (PCR) in detecting Helicobacter pylori (H pylori) infection in patients with bleeding peptic ulcers, and to compare its diagnostic efficacy with other invasive and non-invasive tests.

METHODS: From April to September 2002, H pylori status in 60 patients who consecutively presented with gastroduodenal ulcer bleeding was examined by rapid urease tests (RUT), histology, culture, PCR, serology and urea breath tests (UBT).

RESULTS: The sensitivity of PCR was significantly higher than that of RUT, histology and culture (91% vs 66%, 43% and 37%, respectively; P = 0.01, < 0.001, < 0.001, respectively), but similar to that of serology (94%) and UBT (94%). Additionally, PCR exhibited a greater specificity than serology (100% vs 65%, P < 0.01). However, the specificity of PCR did not differ from that of other tests. Further analysis revealed significant differences in the sensitivities of RUT, culture, histology and PCR between the patients with and those without blood in the stomach (P < 0.01, P = 0.09, P < 0.05, and P < 0.05, respectively).

CONCLUSION: PCR is the most accurate method among the biopsy-based tests to detect H pylori infection in patients with bleeding peptic ulcers. Blood may reduce the sensitivities of all biopsy-based tests.

Changing trends in peptic ulcer prevalence in a tertiary care setting in the Philippines: a seven-year study

BACKGROUND AND AIMS

The declining global prevalence of peptic ulcer disease (PUD) might be because of the decreasing prevalence of Helicobacter pylori (Hp) infection. The aims of the present study were to determine the prevalence of PUD during a 7-year period and to investigate its relationship with the prevalence of Hp infection during the same period.

METHODS

All upper gastrointestinal endoscopies carried out at Santo Tomas Hospital in Manila from January 1996 to December 2002 were evaluated. Endoscopies reporting gastric ulcers (GU) and duodenal ulcers (DU) with Hp status were analyzed.

RESULTS

A total of 15 341 endoscopies were evaluated. Overall, 2600 (16.95%) GU and 1575 (10.27%) DU were identified. There was a decreasing trend in the prevalence of GU (P < 0.0001) and DU (P < 0.0001) during the study period. Overall PUD prevalence declined from 35.87% in 1996 to 18.80% in 2002. This decline was seen for both GU and DU (20.05 vs 14.34%, and 15.83 vs 7.02%, respectively). The prevalence of Hp infection decreased significantly from 1996 to 2002 for both GU and DU (68.13 vs 33.48%, P < 0.0001; and 76.67 vs 36.50%, P < 0.0001, respectively). The decrease in Hp prevalence was significantly related to the decrease in ulcer prevalence (r = 0.97, P = 0.0004 for GU; r = 0.89, P = 0.0079 for DU; and r = 0.92, P = 0.0035 for all PUD). The prevalence of bleeding secondary to PUD remained stable during the 7-year period (P = 0.87).

CONCLUSIONS

During the 7-year period, there was a significant decline in the prevalence of PUD. This decline in PUD prevalence was associated with a corresponding decrease in Hp prevalence.

Mucosal polymerase chain reaction for diagnosing Helicobacter pylori infection in patients with bleeding peptic ulcers

AIM: Helicobacter pylori (H pylori) has been linked to chronic gastritis, peptic ulcers, gastric cancer and MALT-lymphoma. Conventional invasive tests are less sensitive than non-invasive tests in diagnosing H pylori infection in patients with bleeding peptic ulcers. Polymerase chain reaction is a sensitive and accurate method for diagnosing H pylori infection. The aim of this study was to evaluate the diagnostic role of mucosal polymerase chain reaction for H pylori infection in patients with bleeding peptic ulcers.

METHODS: In patients with bleeding, non-bleeding peptic ulcers and chronic gastritis, we checked rapid urease test, histology, bacterial culture and mucosal polymerase chain reaction for detecting H pylori infection. Positive H pylori infection was defined as positive culture or both a positive histology and a positive rapid urease test. For mucosal polymerase chain reaction of H pylori, we checked vacA (s1a, s1b, s1c, s2, m1, m1T, m2), iceA1, iceA2 and cag A.

RESULTS: Between October 2000 and April 2002, 88 patients with bleeding peptic ulcers (males/females: 60/28, gastric ulcers/duodenal ulcers: 55/33), 81 patients with non-bleeding peptic ulcers (males/females: 54/27, gastric ulcers/duodenal ulcers: 45/36) and 37 patients with chronic gastritis (males/females: 24/13) were enrolled in this study. In patients with bleeding peptic ulcers, non-bleeding peptic ulcers and chronic gastritis, 45 patients (51%), 71 patients (88%) and 20 patients (54%) respectively were found to have positive H pylori infection (P<0.001). In patients with bleeding peptic ulcers, non-bleeding peptic ulcers and chronic gastritis, polymerase chain reaction for H pylori infection was positive in 54 patients (61%), 70 patients (86%) and 20 patients (54%) respectively (P<0.001). The sensitivity, positive predictive value and diagnostic accuracy of mucosal polymerase reaction for H pylori infection were significantly lower in patients with bleeding peptic ulcers (84%, 79% and 81%) than in patients with non-bleeding peptic ulcers (99%, 99% and 98%) (P<0.001, P<0.01 and P<0.001 respectively). The sensitivity, negative predictive value and diagnostic accuracy of mucosal polymerase reaction for H pylori were significantly lower in patients with bleeding peptic ulcers (84%, 83% and 81%) than in patients with chronic gastritis (100%, 100% and 100%) (P = 0.02, P = 0.02 and P = 0.001).

CONCLUSION: Mucosal polymerase chain reaction for detecting H pylori infection is not reliable in patients with bleeding peptic ulcers.