Histology compared with chemical testing for urease for rapid detection of Helicobacter pylori in gastric biopsy specimens.

Gastric biopsy specimens from 283 patients with ulcer and non-ulcer dyspepsia attending five gastroenterology clinics in the northern region of the United Arab Emirates (UAE) were tested by the agar gel test (n = 115) or the ultra-rapid endoscopy room test (n = 168) for the presence of Helicobacter pylori urease. Results were compared with a histological technique using the Romanowsky type (Diff-3) stain for detecting H pylori in both antral and body type gastric mucosa. A sensitivity of 94% and specificity of 100% using the agar gel test compared with 87% sensitivity and 99.3% specificity for the ultra-rapid endoscopy room test. Grading of H pylori in gastric biopsy specimens showed that the higher the histological grade, the more likely that the urease test would be positive. Both forms of urease tests have high specificity for detecting H pylori in gastric biopsy specimens, although the urea agar test has a higher sensitivity than the ultra-rapid test. Low numbers of H pylori in gastric biopsy specimens are the most important determinant of a false negative urease test.     

Evaluation of enzyme immunoassay for detection of salivary antibody to Helicobacter pylori.

The Helisal test is a quantitative enzyme immunoassay for the measurement of Helicobacter pylori-specific immunoglobulin G antibodies in saliva. This test was evaluated in comparison with culture and histopathologic examination of gastric biopsy specimens obtained from 195 patients who underwent 200 endoscopic procedures for the investigation of gastrointestinal symptoms. Forty-one (21%) patients were found to have peptic ulcer disease, and one other patient had a gastric carcinoma. H. pylori was detected in gastric biopsy specimens obtained from 98 (49%) of the procedures. The sensitivity, specificity, and positive and negative predictive values of the Helisal test were 81, 75, 76, and 80%, respectively. The test was negative for 16 (38%) of the 42 patients with peptic ulcer disease or a gastric malignancy diagnosed at endoscopy. These results suggest that the Helisal assay is only moderately accurate for the detection of H. pylori infection in symptomatic patients.     

Diagnosis of Helicobacter pylori infection in adult and pediatric patients by using Pyloriset, a rapid latex agglutination test.

Pyloriset (Orion Diagnostica, Espoo, Finland) is a rapid antibody test using latex particles coated with acid-extracted antigen of Helicobacter pylori. We evaluated its ability to predict infection in 100 adult patients and 50 pediatric patients referred for gastric endoscopy. Sixty of 65 H. pylori-infected adults were correctly identified by the test. There were 12 false-positive and 5 false-negative reactions seen. Pyloriset had a sensitivity of 92% and a specificity of 66%. The positive predictive value was 83% and the negative predictive value 82%. In contrast, sensitivity dropped to 36% in the pediatric patients and the positive predictive value was only 40%. Pyloriset could become an important alternative to other more time-consuming diagnostic tests for H. pylori-infected adult patients but is inadequate for diagnosis of pediatric H. pylori infection.     

Evaluation of the novel Helicobacter pylori ClariRes real-time PCR assay for detection and clarithromycin susceptibility testing of H. pylori in stool specimens from symptomatic children

The aim of the present study was to evaluate the Helicobacter pylori ClariRes assay (Ingenetix, Vienna, Austria) for the detection of H. pylori infection and the simultaneous clarithromycin susceptibility testing of the H. pylori isolates in stool samples from 100 symptomatic children. The results obtained by this novel biprobe real-time PCR method were directly compared with the results obtained from histological examination of gastric biopsy specimens, culturing, the [13C]urea breath test, and a monoclonal antibody-based stool antigen enzyme immunoassay (EIA). Fecal specimens from all 54 children who were shown to be noninfected by "gold standard" tests gave true-negative PCR results (specificity, 100%). Of the remaining 46 individuals with a positive H. pylori status, 29 were found to be positive by real-time PCR (sensitivity, 63%). For these 29 cases, the H. pylori ClariRes assay confirmed all results from phenotypic clarithromycin susceptibility testing by Etest. In summary, this investigation demonstrates that detection of Helicobacter DNA in stool samples by real-time PCR is a difficult task and that this method cannot replace the stool antigen EIA (sensitivity, 95.7%) for the accurate diagnosis of H. pylori infection in children.     

Diagnosis of Helicobacter pylori infection by specific gastric mucosal IgA and IgG pylori antibodies.

AIMS--To investigate the diagnostic value of mucosal IgA and IgG Helicobacter pylori antibodies. METHODS--The study population comprised 209 consecutive patients with severe dyspeptic complaints referred for upper gastrointestinal endoscopy. A positive culture or histological identification of H pylori in gastric biopsy specimens, or both, were used to confirm infection. Specific IgA and IgG H pylori antibodies were determined using a modified ELISA technique. RESULTS--Of the 209 patients, 137 were infected with H pylori. The diagnostic value of systemic IgA and IgG H pylori antibodies was confirmed. Systemic IgA antibodies had a sensitivity of 76.6% (95% confidence interval 69.5-83.7) and a specificity of 94.4% (89.1-99.7). The sensitivity and specificity for systemic IgG antibodies were, respectively, 97.1% (94.3-99.9) and 98.6% (95.9-100). A moderate but clinically important correlation was found between local and systemic IgA and IgG. Mucosal IgA H pylori antibodies had a sensitivity of 98.5% (96.5-100) and a specificity of 91.7% (85.3-98.1), while for IgG these figures were, respectively, 88.3% (82.9-93.7) and 98.6% (95.9-100). As a diagnostic test mucosal IgA H pylori antibodies were comparable with culture and histology. CONCLUSION--Determination of local IgA and IgG H pylori antibody levels is a highly sensitive and specific test for the diagnosis of H pylori infection.     

Evaluation of a commercially available second-generation immunoglobulin G enzyme immunoassay for detection of Helicobacter pylori infection.

We evaluated a commercially available second-generation anti-H. pylori immunoglobulin G enzyme immunoassay (EIA) (Cobas Core Anti-Helicobacter pylori EIA; Roche S. A., Basel, Switzerland) for serodiagnosis of H. pylori infection. The results of the assay were assessed in relation to the results of bacterial culture, urease testing, and histological Giemsa stain of gastric biopsy specimens from 1,134 patients with a variety of symptoms relating to the upper gastrointestinal tract. H. pylori was detected in biopsy specimens from 660 (58.2%) patients: 6 had a normal mucosa, 123 had chronic gastritis only, and 531 were found to have chronic active gastritis by histology; endoscopy showed duodenal and gastric ulcers in 137 and 64 patients of the last two groups, respectively. The test was evaluated with different age and ethnic groups. The prevalence, sensitivity, specificity, and positive and negative predictive values were, respectively, (i) for Belgian patients between 18 and 40 years old, 34, 93, 95, 91, and 96%; (ii) for Belgian patients more than 40 years old, 53, 96, 91, 93, and 95%; and (iii) the Mediterranean patients more than 17 years old, 87, 94, 70, 95, and 64%. All sera showing discordant immunoassay results compared with the results of histology and culture of biopsy specimens, as well as those with borderline immunoassay results, were tested further by immunoblotting. Among the EIA results considered false negative, we demonstrated an absence of seroconversion in 14 of 19 patients tested by immunoblotting. Among the EIA results considered false positive, immunoblotting showed the presence of specific antibodies in 28 of 37 patients tested. Among the borderline results obtained in the first assay with 22 patients' sera, a second assay showed positive results in 10 patients (8 were positive by immunoblotting) and negative reactions in 10 patients (9 were negative by immunoblotting), whereas 2 remained borderline. These data indicate that sera showing borderline immunoassay results must be tested again. In conclusion, this commercially available second-generation EIA, which is easy and quick to perform, was found highly reliable for the serodiagnosis of H. pylori infection.     

Detection of Helicobacter pylori DNA in Fecal Samples from Infected Individuals

Stool, gastric biopsy, and serum samples were collected from 22 subjects. DNA from stool was extracted, amplified, and hybridized with primers specific for the 16S rRNA gene of Helicobacter pylori. DNA from gastric biopsy specimens was analyzed similarly for comparison. Universal primers were used to confirm successful extraction of DNA from samples. Histologic, serologic, and DNA analyses were scored in a blinded fashion. Universal primer amplification verified successful DNA extraction from all stool and gastric tissue specimens. The gastric tissue DNA assay was positive for H. pylori in 11 of the 22 subjects, correlating completely with histologic and serologic results. Stool DNA was positive for H. pylori by our molecular assay in 8 of these 11 H. pylori-positive subjects. All subjects who were negative by histologic, serologic, and gastric tissue DNA analyses were also negative by stool DNA analysis. Compared to histology, serology, and gastric tissue DNA analyses, the sensitivity of our stool DNA assay was 73%, with a specificity of 100%.     

Helicobacter pylori in dyspeptic patients in Kuwait.

Two hundred and four patients, mainly Arabs, attending for upper gastrointestinal endoscopy at the gastroenterology clinic in Mubarak Al-Kabeer Hospital, Kuwait, were examined for evidence of infection with Helicobacter pylori and associated inflammation. Biopsy specimens of antrum, body, and duodenum; gastric juice; and antral mucosal brushings were investigated by microbiological, cytological, and histopathological methods. Clinical conditions diagnosed at endoscopy included gastritis, gastric ulcer, duodenitis and duodenal ulcer, but half the patients had endoscopically normal gastric and duodenal mucosae. H pylori was detected by one or more of the procedures in at least one specimen from 197 (96.6%) of the patients. Histological and cytological analysis showed equal sensitivity, but bacteriological culture was less reliable. The proportion of positive cases was high, compared with other reported series, which may have been accounted for by the variety of diagnostic techniques used in this study, the selected population (all with gastrointestinal symptoms) or genetic or environmental predisposing factors peculiar to the sample population.     

The Utility of the helicobacter pylori stool antigen test in managing dyspepsia: an experience from a low resource setting

Background

Dyspepsia is defined as a chronic or recurrent pain or discomfort centered in the upper abdomen. Endoscopy is the best strategy for confirming the cause of dyspepsia. Non- invasive strategies would be more appropriate in low resource countries where endoscopy is not readily available. However, there is concern that these strategies may miss serious disease like gastric cancer. One test that needs to be assessed in this regard is the Helicobacter pylori stool antigen test (HPSAT).

Objective

To determine the validity of the stool antigen test in predicting H. pylori associated disease among patients with dyspepsia.

Methods

In this prospective study patients with dyspepsia attending Mulago Hospital were recruited consecutively. Helicobacter pylori was determined using the Rapid Strip HpSA ®, endoscopy and gastric mucosal biopsy were done.

Results

167 patients with dyspepsia were recruited into the study. There were ninety six (57.5%) females and seventy one (42.5%) males with an average age of 48.1(±18.1) years. Patients presenting with dyspepsia in Mulago hospital were more likely to come from the Central 60 (36%) and western tribes 55 (33%). The commonest endoscopic finding was oesophagitis 25 (15%). Peptic ulcer disease was found in 32 (19.2%) and 54 (32.3%) had normal endoscopy findings. H pylori was found in 33.5% and 32.5% using the HPSAT and histology respectively. The validity of the HPSAT in predicting H.pylori associated diseases was generally low with an overall sensitivity of 55.8%, and specificity of 74.2%. However, the validity was higher in predicting the diagnosis of peptic ulcer disease with a sensitivity 59.4% and specificity 72.6%.

Conclusion and recommendations

The HPSAT may be used in the test and treat strategy for young patients with dyspepsia without alarm signs and symptoms in low resource settings. However, because of its low validity in predicting H.pylori associated disease, it is important to follow up patients so that if symptoms persist or recur endoscopy is performed     

Evaluation of the Helicobacter pylori stool antigen (HpSA) test in routine clinical practice--is it patient-friendly?

A new immunoassay has been developed to detect the presence of Helicobacter pylori antigens in stool specimens. The aim of our study was to assess the accuracy and utility of the H. pylori stool antigen (HpSA) test in routine clinical practice. Dyspeptic patients undergoing endoscopy were studied. H. pylori status was defined before treatment by CLOtest and histology, and by 13C urea breath test (UBT) after eradication therapy. A standard universal container was provided for stool collection and the HpSA test was performed by an investigator blind to the results of the other diagnostic tests. Patients also provided a venous blood sample prior to endoscopy for H. pylori serology. Sixty patients (30 M : 30 F: mean age 47 yr) were enrolled in the study. The pretreatment sensitivity, specificity, positive and negative predictive value of the HpSA test were respectively, 93%, 94%, 96%, and 90%. Twenty five patients returned for post treatment 13CUBT, but only 14 (56%) provided a stool sample for analysis. The post treatment sensitivity, specificity, positive and negative predictive value of the HpSA test were respectively, 67%, 100%, 67%, and 92%. The HpSA test was negative in 19% of the patients found positive for anti-H. pylori antibodies on serology testing. All H. pylori antibody-negative patients had a negative HpSA test. Our results suggest that the HpSA test provides accurate pretreatment diagnosis of H. pylori infection but the reliability of the test after treatment is uncertain. A potential problem with the HpSA test appears to be patient reluctance about stool handling and this could prove a significant obstacle to patient compliance and the acceptability of the test in everyday clinical practice.     

Helicobacter pylori in gastroduodenal diseases

OBJECTIVE: To determine the prevalence and disease association of Helicobacter pylori (H. pylori) in dyspeptic patients in southwest Nigeria. Setting: Obafemi Awolowo University Teaching Hospitals Complex, Ile-lfe, Nigeria. METHODS: Consecutive dyspeptic patients for upper gastrointestinal endoscopy from January 1996 to March 1997 were investigated for H. pylori in gastric biopsy by histopathology and culture. Patients without gastroduodenal ulcerations or neoplastic lesions constituted the nonulcer dyspeptic (NUD) group. RESULTS: 138 (92 males, 46 females) patients aged 4.5-85 years [mean (7) = 45+/-SD 17.8 years] who had upper gastrointestinal endoscopy were analyzed for presence of H. pylori. Eighty-three had histopathology alone, while 55 others had both histology and culture. Endoscopic diagnosis included duodenal ulcer (DU) (n=35, 23%); gastric ulcer (n=4, 3%); gastric cancer (n=14, 9%); NUD, including gastritis (n=49, 32%); duodenitis (n=47, 31%); and normal (n=16, 11%). Overall, H. pylori was positive in 107 of 138 (77.5%) patients. There was a significant association of H. pylori with DU and NUD (p<0.000). Three-quarters of cases of normal endoscopy harbored H. pylori. The finding of 80% and 85% H. pylori in gastritis and duodenitis, respectively, was of interest. CONCLUSIONS: These findings suggest that DU and NUD were the main clinical expressions of H. pylori infection in southwest Nigerian dyspeptic patients similar to what is found in developed nations. Of note is the high incidence of H. pylori in endoscopically normal patients.     

Use of Helicobacter pylori-specific antibodies in the evaluation of intestinal metaplasia and gastric dysplasia

It is believed that Helicobacter pylori acts mainly during the initial phases of gastric carcinogenesis. Therefore, this study aims to assess the usefulness of H. pylori diagnosis in patients with chronic gastritis (CG), intestinal metaplasia (IM) and dysplasia--conditions that are associated with gastric cancer. A cross-sectional study of 94 patients was performed, which involved endoscopic biopsy and determination of specific serum anti-H. pylori antibodies (IgA, IgG and IgM) by enzyme-linked immunosorbent assay (ELISA). Biopsies were taken from the gastric antrum and corpus, and from endoscopic lesions. Two specimens per patient were used for bacterial culture. H. pylori infection status, used as the gold standard, was based on culture results. Validity measures were determined and receiver operating curve (ROC) was used to determine the best cut-off for serum antibody levels. Histopathological evaluation (n = 160) was performed independently by two pathologists. Lesions consistent with CG were found in 86 patients (91%), consistent with IM in 69 patients (73%) and with dysplasia in five patients (5%). In the 86 patients with CG, 38 (44%) were infected by H. pylori, as were 26 (38%) and one (20%) with IM and dysplasia, respectively (P=0.039). Area under the curve (AUC) was 0.40 (95% confidence interval [CI]: 0.28-0.51) for IgM, 0.69 (0.58-0.80) for IgA and 0.83 (0.74-0.92) for IgG for the diagnosis of H. pylori infection. Best cut-off was 41 u/mL for IgG, with a sensitivity (95% CI) of 90% (84-96%) and a negative predictive value (NPV) of 91% (85-97%). For IgA the results were 22 u/mL, 74% (65-83%) and 77% (68-86%), respectively. Prevalence of H. pylori appeared to decrease with increasing severity of the gastric lesion. In conclusion, it is suggested that non-invasive serological evaluation of anti-H. pylori (IgG) status after eradication therapy for peptic ulcer disease could be extended, after proper assessment of cut-off values and their validation, to the follow-up of patients with CG and IM.     

Isolation and preliminary evaluation of a low-molecular-mass antigen preparation for improved detection of Helicobacter pylori immunoglobulin G antibodies.

Previously, immunoglobulin G (IgG) antibodies to five antigens with a relative molecular mass of between 15 and 30 kDa from Helicobacter pylori were found to be significantly more frequent in H. pylori-infected patients than in noninfected patients. In this study, these specific low-molecular-mass (LMW) antigens were separated by ultrafiltration of whole-cell sonicates. The LMW antigen preparation was evaluated by enzyme-linked immunosorbent assay with serum samples from 76 children with abdominal symptoms and 151 adults with dyspeptic symptoms. H. pylori was cultured or seen in 40 (53%) children and 83 (55%) adults. Increased antibody levels to H. pylori were found in serum from 35 (46%) children and 88 (58%) adults. Values for sensitivity, specificity, and predictive value of positive and negative results of the test were higher with LMW antigens than with the heat-stable antigen previously described. The low specificity and predictive value of a positive result were due to seropositive results for 21 persons with a negative culture for H. pylori and negative microscopy results for Helicobacter-like organisms in biopsies from gastric mucosa. Histologically, chronic gastritis was demonstrated in 43% of these persons, and 19% had peptic ulcer, indicating that they have or have had H. pylori infection. Specific antibodies to H. pylori were confirmed in all 21 patients by the Western immunoblot technique. Use of the LMW antigen improved the IgG antibody detection in patients with H. pylori infection, even though the results reflect the difficulties in establishing a true gold standard for diagnosis of H. pylori infection.     

Effect of transport medium and transportation time on culture of Helicobacter pylori from gastric biopsy specimens.

To determine whether transportation time and use of a low budget transport medium (NaCl 0.9%) would influence culture of Helicobacter pylori from gastric biopsy specimens, upper gastrointestinal endoscopy was performed on 42 patients. The specimens were cultured and examined histologically, and H pylori antibodies were determined using an ELISA technique. Patients were regarded as H pylori positive when culture was positive or when histology or IgG anti-H pylori antibodies indicated H pylori infection. Rapid transportation of gastric biopsy specimens in NaCl 0.9%, at room temperature resulted in a high diagnostic yield (23 H pylori positive cultures in 26 patients with H pylori infection). A 24 hour delay in plating gastric biopsy specimens after transportation in NaCl 0.9%, at room temperature, did not seriously affect results (22 instead of 23 H pylori positive cultures). The culture results after transportation in Cairy-Blair medium were comparable with those after transportation in NaCl 0.9%, but because of availability, low cost, and ease of handling in the endoscopy department, NaCl 0.9% was preferred as transport medium. This study shows that for culture of H pylori from gastric biopsy specimens sterile saline is an adequate medium, and that transportation can be delayed for 24 hours without a significant loss of diagnostic yield.     

Association of Helicobacter pylori with gastritis and peptic ulcer diseases

The occurrence of Helicobacter pylori(H.pylori) and its relationship with gastric mucosa were studied by light and electron microscopy and culture of biopsy specimens from gastric mucosa of 160 patients with upper gastrointestinal symptoms. H. pylori were present in 96.6% of patients with active chronic gastritis, 100% of patients with duodenal ulcer and 76.9% of patients with gastric ulcer, while present in only 6.3% of individuals with histologically normal gastric mucosa. The bacteria colonized the antral mucosa more frequently than the body or than the duodenal cap mucosa. The bacteria were rarely seen in the intestinalized epithelium per se, but there was no significant difference in prevalence of H. pylori between gastritis with intestinal metaplasia and gastritis without intestinal metaplasia. H. pylori could be seen in close association with the surface of gastric epithelial cells below the mucus layer without evidence of intracellular parasitism, All of the strains tested were susceptible to penicillin, erythromycin, and most of them susceptible to tinidazole and bismuth salts. It is concluded that H. pylori are highly associated with gastritis and peptic ulcer diseases and its prevalence rates in patients with those diseases is higher than in developed countries. This strong association of H. pylori infection with gastritis and peptic ulcer diseases suggest a possible etiologic role for the bacterium in those diseases.     

Use of the Abbott Architect HIV antigen/antibody assay in a low incidence population

BackgroundWith the availability of 4th generation HIV diagnostic tests which are capable of detecting acute infection, Iowa evaluated the 3rd and 4th generation HIV test and compared the performance of these products in a low incidence population.ObjectiveThis study was conducted to evaluate the performance of an HIV antigen/antibody combination (4th generation) assay compared to an EIA 3rd generation assay.Study designOver a 4 month period, 2037 specimens submitted for HIV screening were tested by Bio-Rad GS HIV-1/HIV-2 Plus O EIA and the Abbott Architect i1000SR HIV Ag/Ab Combo. The performance characteristics of sensitivity, specificity, positive predictive value and negative predictive value were determined.ResultsOf the 2037 specimens tested, there were 13 (0.64%) true positives detected. None of the positive specimens were from patients in the acute phase of infection. The Abbott antigen/antibody combo assay had a sensitivity, specificity, positive-predictive value and negative predictive value of 100%, 99.85%, 81.25%, and 100% respectively. The Bio-Rad EIA assay had a sensitivity, specificity, positive-predictive value and negative predictive value of 100%, 99.80%, 76.47% and 100%, respectively. The EIA had four false positive results which tested negative by the antigen/antibody assay and western blot.ConclusionIn a low-incidence state where early infections are less commonly encountered, the EIA assay and the antigen/antibody assay performed with near equivalency. The antigen/antibody assay had one less false positive result. While no patients were detected in the acute stage of infection, the use of the antigen/antibody assay presents the opportunity to detect an infected patient sooner and prevent transmission to others.     

Diagnosis of Helicobacter pylori infection by PCR: comparison with other invasive techniques and detection of cagA gene in gastric biopsy specimens.

A PCR assay for the detection of Helicobacter pylori in gastric biopsy specimens with specific primers for ureC gene amplification (herein referred to as ureC PCR) was compared with other routine invasive methods (culture, the rapid-urease test, and Giemsa staining of histological sections) with samples from a group of 104 consecutive dyspeptic patients. Bacteria were found in 40 (38.5%), 38 (36.5%), 36 (34.6%), and 35 (33.7%) of the patients by ureC PCR, culture, the rapid-urease test, and Giemsa stain, respectively. Sixty-three patients had negative cultures, negative histological examinations, and negative rapid-urease test results, and 61 of these patients were also negative by ureC PCR. ureC PCR detected H. pylori in two culture-negative patients. In parallel, a PCR-based assay to detect the H. pylori cytotoxin-associated antigen (cagA) gene, a putative virulence gene, was also developed. To assess the likelihood of detection of H. pylori genes directly from gastric biopsy samples and from the corresponding H. pylori isolates, specimens from 31 patients were subjected to PCR with ureC- and cagA-targeting primers. All 31 biopsy specimens and the corresponding H. pylori isolates were positive in the ureC PCR. H. pylori strains that were cagA positive also gave positive cagA PCR fragments with biopsy specimens from the same patients. All ureC PCR-positive patients were examined; biopsy specimens from 10 of 11 (91.7%) duodenal ulcer patients harbored H. pylori cagA-positive strains, whereas 19 of26 (73%) of those from patients with chronic gastritis only were found to be cagA positive.(ABSTRACT TRUNCATED AT 250 WORDS)     

Serological and direct diagnosis of Helicobacter pylori in gastric carcinoma: a case-control study

This study evaluated the sensitivity of serological and direct methods for the diagnosis of Helicobacter pylori infection in 127 patients with gastric carcinoma and in 127 controls without this disease, matched for age and sex. Antral and oxyntic mucosal specimens were obtained from all patients, at operation in patients with gastric carcinoma and at endoscopy from controls. The urease test, microscopy of stained smears and culture for H. pylori were performed on all specimens. Sera from all patients were tested for antibodies to H. pylori by a highly sensitive and specific IgG-ELISA. Culture, urease test, stained smear and ELISA were significantly less sensitive in the patients with gastric carcinoma than in control subjects. However, the combination of several methods improved the diagnosis of H. pylori infection in the gastric carcinoma group. Infection was significantly more frequent in the gastric carcinoma patients than in the controls. H. pylori infection was associated with an increased risk of developing gastric carcinoma.     

The comparison of histologic gastritis in patients with duodenal ulcer, chronic gastritis, gastric ulcer and gastric cancer

This study was designed to investigate the differences of histologic gastritis according to the endoscopic diagnosis, and between H. pylori positive and negative gastritis, using the Sydney system. A total of 122 patients (42 duodenal ulcer, 31 chronic gastritis, 35 gastric ulcer and 14 gastric cancer) underwent endoscopy with biopsies from the antrum and body. Among the 122 patients, 104 (85%) were H. pylori positive. H. pylori density of the antrum was significantly higher in duodenal ulcer than in chronic gastritis, gastric ulcer, and gastric cancer. The positivity of intestinal metaplasia was lowest in duodenal ulcer and highest in gastric cancer. H. pylori density as well as grade of activity, inflammation and atrophy were significantly higher in the antrum than in the body in duodenal ulcer, while in chronic gastritis, gastric ulcer and gastric cancer there was no difference of H. pylori density, activity, inflammation and atrophy between the antrum and body. The grade of activity and chronic inflammation were significantly higher in H. pylori positive patients than in H. pylori negative patients in both the antrum and body. In conclusion, the gastritis of duodenal ulcer was mainly localized to the antrum, while the gastritis of chronic gastritis, gastric ulcer or gastric cancer was rather uniform in the antrum and body. H. pylori seemed to be related to the development of chronic inflammation and activity.     

Comparison of three stool antigen tests for Helicobacter pylori detection

BACKGROUND: Active Helicobacter pylori infection can be diagnosed by invasive (biopsy based) or non-invasive methods, such as stool antigen testing. AIMS: To compare three stool antigen enzyme immunoassay kits--Premier Platinum Hp SA, FemtoLab Cnx, and Hp Ag--with biopsy based methods for the detection of H pylori in previously undiagnosed patients. METHODS: One hundred and eleven adults with dyspepsia referred for endoscopy provided a stool sample for testing and had biopsies taken. Patients were considered H pylori positive if two out of three invasive tests were positive or if culture alone was positive. RESULTS: The sensitivities and specificities of the Premier Platinum Hp SA, FemtoLab Cnx, and Hp Ag stool antigen kits when compared with biopsy based diagnosis were, 63.6%, 88.0%, and 56.0% and 92.6%, 97.6%, and 97.6%, respectively. CONCLUSIONS: FemtoLab Cnx may be considered as an alternative to urea breath testing in the initial diagnosis of patients with dyspepsia who do not require immediate endoscopy. Stool testing has the potential advantages of being simple to perform, relatively cheap, and samples can be submitted directly from primary care.