Factors that affect results of the 13C urea breath test in Japanese patients

Background. The ¹³C urea breath test (UBT) is considered to be the most accurate way of diagnosing Helicobacter pylori infection. Our objective was to investigate the accuracy of the UBT in Japanese patients and the association of UBT values with histological findings.
Materials and Methods. A total of 169 consecutive patients were studied by endoscopy with histology, by serology with IgG antibody and test serum pepsinogen (PG), and by UBT. The association between UBT values and histological findings and the PG I / II ratio were analyzed in H. pylori –positive patients.
Results. Of 169 Japanese patients, 135 were H. pylori –positive on both histology and serology analysis, 27 were H. pylori –negative on both histology and serology analysis, and 7 patients showed differing results. Using a cutoff value of 2.5‰, test sensitivity was 100%, while specificity was 96%. Among the 135 H. pylori –positive patients, a significant relation was observed between UBT value and H. pylori colonization density of the corpus and antrum, neutrophil activity of the antrum, atrophy, and intestinal metaplasia of the corpus in the H. pylori –positive patients. Also, UBT values correlated with the PG I /II ratio. In multivariate analysis, the PG I /II ratio was the most important factor related to UBT values (odds ration [OR], 4.99; 95% confidence interval, 1.60–15.55).
Conclusions. The UBT is an accurate method for detecting H. pylori infection in the Japanese population, which shows a high prevalence of atrophic gastritis. Values are affected by H. pylori infection and by the severity of atrophic gastritis.     

CagA and VacA are immunoblot markers of past Helicobacter pylori infection in atrophic body gastritis

BACKGROUND AND AIM: Atrophic body gastritis (ABG) may be induced by H. pylori infection. It is difficult to diagnose H. pylori infection in this condition, since during progression of body atrophy the bacterium disappears. In 30% of patients with ABG no sign of H. pylori infection is detectable. We aimed to investigate whether patients with ABG, classified as H. pylori-negative by conventional methods (ELISA serology and Giemsa stain histology), have been previously exposed to the infection. METHODS: Case series consisted of 138 outpatients with ABG, of whom 31 are H. pylori negative (histology and ELISA serology), and 107 are H. pylori related (histology and ELISA serology positive: active infection, n = 29; only serology positive: past infection, n = 78). Thirty control subjects who were H. pylori negative at histology and ELISA serology were investigated. Immunoblotting of sera against H. pylori whole-cell protein lysate was performed. RESULTS: None of the control sera recognized CagA, VacA, heat-shock protein B, and urease B, yielding a specificity of 100%. All H. pylori-negative patients with ABG showed immunoblotting seroreactivity, including in each case either CagA or VacA. The concomitant seroreactivity against CagA and VacA was highly prevalent in the H. pylori-negative patients with ABG, comparable to those with active infection (77.4% vs. 86.2%) and with past infection (vs. 61.5%). CONCLUSIONS: Immunoblotting against CagA and VacA is able to prove past exposure to H. pylori infection in all patients with ABG defined as H. pylori-negative by conventional methods, suggesting a hidden role of H. pylori infection in gastric atrophy also in these patients.     

改良幽门螺杆菌抗原检测试剂盒 检测粪便幽门螺杆菌抗原的临床评价

目的评估改良幽门螺杆菌抗原检测试剂盒检测粪便幽门螺杆菌抗原(Helicobacter pylori stool antigen,HpSA)的准确性以及临床应用价值。方法采用随机、双盲、双验证和与~(13) C呼气试验(~(13) C-UBT)对比的方法,对门诊175例接受~(13) C-UBT检测的患者,采用最新研制出的一种改良幽门螺杆菌抗原检测试剂盒(胶体金法)检测粪便幽门螺杆菌抗原,以~(13) C-UBT检测结果为诊断H.pylori感染的"金标准",并将两者进行对比研究,所有检测结果均拍照存档,采用随机、双盲和双验证法,以期客观真实地评价改良幽门螺杆菌抗原检测试剂盒检测粪便幽门螺杆菌的效果。结果改良幽门螺杆菌抗原检测试剂盒检测HpSA敏感度为90.48%,特异度为90.00%,Youden指数为80.48%,Kappa值为0.799;HpSA检测ROC曲线下面积为0.902±0.027,与完全无诊断价值的机会线下面积0.50相比,差异有统计学意义(P=0.000);Spearman相关系数r=0.800,P=0.000。结论改良幽门螺杆菌抗原检测试剂盒能准确检测H.pylori感染,其操作简便,可作为非侵入性诊断H.pylori感染筛查以及流行病调查的一种方法,将来有望成为患者家庭自查幽门螺杆菌的一种方法。     

13C-urea breath test to assess Helicobacter pylori bacterial load

BACKGROUND: Some authors have reported, using different protocols, that 13C-urea breath test (13C-UBT) is capable of assessing the intragastric Helicobacter pylori bacterial load, whereas others have not confirmed these data. Our aim is to evaluate the correlation between 13C-UBT values and H. pylori bacterial load. MATERIALS AND METHODS: One hundred ninety-two patients diagnosed H. pylori-positive by rapid urease test, histology, and 13C-UBT were enrolled. H. pylori bacterial load (H. pylori score) and gastritis activity (activity score) were evaluated according to the Updated Sydney System. 13C-UBT was performed according to the European Standard Protocol. Breath samples were obtained every 10 minutes for 60 minutes in 52 patients and at 30 minutes (T30) in 140 patients and analyzed by mass spectrometry. RESULTS: At T30, mean +/- SD excess delta 13CO2 excretion was 17.4 +/- 1.1, 29.9 +/- 2.2, and 48.7 +/- 4.8 in patients with H. pylori scores 1, 2, and 3, respectively. This difference was statistically significant: H. pylori score 1 versus 2, p < .005; score 1 versus 3, p < .05; score 2 versus 3, p < .05. A significant positive correlation (G = 0.59) was found between H. pylori score and activity score of chronic gastritis. At T40 and T50 significant correlation between mean excess delta 13CO2 excretion and bacterial load was achieved only in patients with H. pylori scores 1 and 3. CONCLUSIONS: 13C-UBT European Standard Protocol values correlate with H. pylori bacterial load and the activity of gastritis at T30 breath sampling time.     

Eradication of Helicobacter pylori infection equally improves chronic urticaria with positive and negative autologous serum skin test

BACKGROUND: The aim of the study was to examine effects of Helicobacter pylori eradication on chronic idiopathic urticaria (CU) with and without positive aulogous serum skin test (ASST). METHODS: Seventy-eight patients with CU were checked for the positivity ASST and H. pylori urea (13)C-urea breath test ((13)C-UBT). Twenty-one patients were with both positive ASST and positive (13)C-UBT (group A), and 24 patients were with negative ASST and positive (13)C-UBT (group B). All patients with positive (13)C-UBT received a 14-day, open treatment with amoxicillin 1 g b.i.d., clarithromycin 500 mg b.i.d., and omeprazole 20 mg b.i.d. H. pylori eradication was assessed by a second (13)C-UBT after 8 weeks. In control group, 33 patients with CU were included. The effect of H. pylori eradication on CU was evaluated by urticaria activity score (UAS), measured at study entry and at 8 and 16 weeks. RESULTS: At week 8, baseline UAS reduced from 4.7 +/- 1.1 to 2.4 +/- 1.4 (p = .027) in group A and from 4.3 +/- 1.5 to 2.3 +/- 1.2 (p = .008) in group B, without statistically significant difference between the two groups. In control group and in six patients with H. pylori eradication failure, no changes of UAS were noted. CONCLUSION: Eradication of H. pylori infection by triple therapy significantly and equally reduces UAS in CU patients with positive and negative ASST.     

Validation of Diagnostic Tests for Helicobacter pylori with Regard to Grade of Atrophic Gastritis and/or Intestinal Metaplasia

Background and Aims:  To evaluate the validity of the biopsy-based tests (histology, culture, and urease test) and serology in detecting current Helicobacter pylori infection against a background of atrophic gastritis (AG) or intestinal metaplasia (IM).
Methods:  Helicobacter pylori infection was diagnosed in 651 subjects, using the predefined gold standard for H. pylori tests. The sensitivity, specificity, and positive and negative predictive values of culture, CLOtest, histology (Giemsa stain), and serology were calculated with regard to the histological grade of AG and IM. The level of serum pepsinogen (PG) I and II was also measured as a marker for the presence of AG.
Results:  In the study population (n = 651), sensitivity and specificity, respectively, were as follows: culture, 56.2 and 100%; histology, 93.0 and 94.0%; CLOtest, 80.4 and 96.7%; serology, 96.0 and 67.5%. If the analysis is limited to those without AG or IM (n = 158) or to those younger than 40 years (n = 69), all tests, except for culture, had a sensitivity and specificity >90%. The sensitivity of CLOtest and the specificity of serology markedly decreased with progression of AG and IM, and serology was less specific in the presence of AG, as determined by a PG I/II ratio ≤4.1 (specificity, 83.7% vs 40.7% in PG I/II >4.1 and ≤4.1, respectively).
Conclusions:  Any one of biopsy-based tests or serology was found to be excellent for identifying current H. pylori infection among individuals without AG or IM and/or younger patients (<40 years). However, a combination of at least two tests is necessary in the clinical setting of AG or IM.     

Comparison of a Stool Antigen Test and Serology for the Diagnosis of Helicobacter pylori Infection in Mass Survey

Background: Serum antibody to Helicobacter pylori is tested in mass screening for gastric cancer along with the level of serum pepsinogens (PG) I and II. Recently, stool antigen tests have been developed as a new non-invasive test. We examined H. pylori infection by both serology and stool antigen test in a mass survey and compared the results to estimate applicability of stool antigen test for mass survey.
Methods: A total of 994 healthy adults who received mass survey in April 2005 were tested. There were 379 men and 615 women, and the mean age was 57.7 years old. Stool samples were used to measure a H. pylori- specific antigen by enzyme immunoassay. Serum samples were tested for the prevalence of IgG antibody to H. pylori , and the level of PGs I and II was also measured to determine the presence of atrophic gastritis.
Results: Infection of H. pylori was defined as positive 61.4% and 56.4% by serology and stool antigen test, respectively. The concordance of both tests was not affected by gender and age of the subjects but difference was seen in subjects with atrophic gastritis. In particular, positivity of stool antigen test (81.8%) was significantly lower than that of serology (88.7%, p  < .05) in 303 subjects with severe atrophic gastritis.
Conclusions: Stool antigen test, which detects present but not previous infection of H. pylori , would be applicable to diagnose H. pylori infection in mass survey. Usefulness of stool antigen tests for the screening of gastric cancer should be examined.     

13C-urea breath test to diagnose Helicobacter pylori infection in children aged up to 6 years

BACKGROUND: 13C-urea breath test (13C-UBT) is an accurate noninvasive tool for diagnosis of Helicobacter pylori infection. It is considered the best method for epidemiological studies, but there are few studies to evaluate the 13C-UBT in infants and toddlers. AIM: To evaluate the 13C-UBT performed with infrared spectroscopy in children aged up to 6 years. PATIENTS: Sixty-eight patients (6 months. to 5 years 11 months.) were evaluated prospectively and consecutively. METHODS: Helicobacter pylori infection was detected by positive culture, or rapid urease test and histological examination, both positive. 13C-UBT was performed with 50 mg of 13C-urea diluted in 100 ml of commercial orange juice. Two expired air samples were collected: before and 30 minutes after tracer ingestion. Cutoff of delta over baseline (DOB) was 4.0 per thousand and urea hydrolysis rate 10 microg/minute. RESULTS: Fifteen of 68 (22.1%) patients were H. pylori infected. Sensitivity was 93.3% (95% CI; 86.8%-99.7%) and specificity was 96.2% (95% CI; 93.6%-98.8%), and these values were equal for DOB and urea hydrolysis rate. Negative DOB values in noninfected patients ranged from -1.5 per thousand to 2.6 per thousand and positive DOB values ranged from 10.8 per thousand to 105.5 per thousand. There was no relationship between DOB values and age. Conclusion. 13C-UBT performed with infrared spectroscopy proved to be a reliable and accurate noninvasive diagnostic tool for H. pylori infection detection in children aged up to 6 years. Results far from cutoff value can clearly distinguish positive from negative 13C-UBT results in children up to 6 years old.     

Usefulness of non-invasive tests for diagnosing Helicobacter pylori infection in patients undergoing dialysis for chronic renal failure

BACKGROUND: Helicobacter pylori infection in chronic renal failure patients has been linked to peptic ulcer and gastric neoplasia after kidney transplantation. It may also contribute to the accelerated arteriosclerosis that is usual in this population. Few data are available on the usefulness of noninvasive diagnostic tests for H. pylori infection in dialyzed patients, especially regarding the new fecal antigen detection tests. The objective of this study was to determine the efficacy of a noninvasive test for H. pylori infection in patients with chronic renal failure. METHODS: Eighty-six patients were included in a cross-sectional study. Urea breath test, serology and three fecal tests--FemtoLab H. pylori (Connex, Germany), Premier Platinum HpSA (Meridian, USA) and Simple H. pylori (Operon SA, Spain) were performed. Helicobacter pylori status was determined by concordance of the tests. Sensitivity, specificity and positive and negative predictive values were calculated for each test. RESULTS: Sensitivity, specificity, positive and negative predictive values were 94%, 96%, 94% and 96% for the urea breath test; 97%, 64%, 66% and 97% for serology; 86%, 100%, 100% and 91%, for FemtoLab H. pylori; 58%, 96%, 91% and 76% for Premier Platinum HpSA and 61%, 78%, 74% and 67% for Simple H. pylori. CONCLUSIONS: The urea breath test seems to be the most reliable diagnostic method for H. pylori infection in patients with chronic renal failure. Serology has a low specificity, and the results of the fecal tests vary widely.     

Gastroduodenal lesions and Helicobacter pylori infection in dyspeptic patients with and without chronic renal failure

BACKGROUND: Patients with chronic renal failure (CRF) often have dyspeptic symptoms and may develop peptic disease or digestive disorders leading to severe gastrointestinal complications. The primary aim of this study was to evaluate the prevalence of peptic lesions and Helicobacter pylori infection, and the severity of dyspeptic symptoms, in dyspeptic patients with and without CRF. Our secondary aim was to investigate whether uremic status may affect the diagnostic efficiency of the [13]C-urea breath test ([13]C-UBT). PATIENTS AND METHODS: We consecutively enrolled in the study 50 dyspeptic patients with chronic kidney failure (mean age 52 +/- 5 years), of whom 11 were on hemodialysis treatment (HD), and 93 subjects (mean age 54 +/- 7 years) with chronic dyspepsia and normal renal function (NRF). All patients completed an oriented and validated questionnaire scoring the severity of nine dyspeptic symptoms (i.e. epigastric pain, epigastric burning, postprandial fullness, early satiety, bloating, belching, nausea and vomiting) and underwent upper endoscopy with multiple bioptic sampling for rapid urease test and histological examination, [13]C-UBT and HpSA test. RESULTS: The prevalences of peptic lesions and H. pylori infection and mean symptom score were 74%, 52% and 3.5 +/- 3, respectively, in dyspeptic patients with CRF and 18%, 36% and 8 +/- 5, respectively, in dyspeptic patients with NRF. The diagnostic accuracy of [13]C-UBT with respect to histological diagnosis was 94% and 97% for dyspeptic patients with and without renal failure, respectively. CONCLUSIONS: 1, A high frequency of peptic lesions and low symptom scores were observed in uremic patients in spite of H. pylori infection; 2, uremic status did not affect the diagnostic accuracy of [13]C-UBT.     

Evaluation of a novel monoclonal-based antigen-in-stool enzyme immunoassay (Premier Platinum HpSA PLUS) for diagnosis of Helicobacter pylori infection in Vietnamese children

Background: Helicobacter pylori infection is difficult to diagnose in children, especially in developing countries where noninvasive methods such as urea breath test are often not available. We evaluate the sensitivity and specificity of a new monoclonal antibody-based antigen-in-stool enzyme immunoassay (Premier Platinum HpSA PLUS) for diagnosis of H. pylori infection in Vietnamese children.
Materials and Methods: Sensitivity of the antigen-in-stool test was evaluated in 232 children, 3–15 years of age, who were positive for H. pylori infection by culture from biopsies. For evaluation of the specificity 98 children of similar age with nongastrointestinal conditions and who were negative for H. pylori infection by serologic assays were included with blood and stool samples.
Results: Of the 232 culture-positive children, 224 were also positive by Premier Platinum HpSA PLUS. Of the 98 control children, 93 were H. pylori negative also in the stool test. The sensitivity of Premier Platinum HpSA PLUS was thus 96.6% (95% CI 93.3–98.5) and the specificity was 94.9% (95% CI 88.5–98.3).
Conclusions: The findings have demonstrated Premium Platinum HpSA PLUS to be a reliable method for detection of H. pylori infection also in children in our area.     

Novel monoclonal antibody-based Helicobacter pylori stool antigen test

BACKGROUND: A number of noninvasive tests have been developed to establish the presence of Helicobacter pylori infection. Although polyclonal antibody-based stool antigen testing has a good sensitivity and specificity, it is less accurate than urea breath testing. Recently, a monoclonal antibody-based stool antigen test demonstrated an excellent performance in diagnosing H. pylori infection in adults and in pediatric populations. AIM: To evaluate the diagnostic accuracy of a novel stool test based on monoclonal antibodies to detect H. pylori antigens in frozen human stool in the pretreatment setting. PATIENTS AND METHODS: Stool specimens were prospectively collected from 78 patients undergoing gastroscopy and stored at -20 degrees C until tested. Helicobacter pylori infection was evaluated by histology, rapid urease testing and urea breath tests ((13)C-UBT). Positivity of the three tests was considered the gold standard for H. pylori active infection. Patients with no positive test were considered negative. The gold standard was compare to the results of the monoclonal antibody stool antigen test. Frozen stool specimens were tested using a novel monoclonal-antibody-based enzyme immunoassay (HePy-Stool, Biolife-Italiana, Milan, Italy). RESULTS: The sensitivity and specificity of the monoclonal stool antigen test were 97%[95% confidence interval, (CI) 86-100] and 94% (95% CI: 81-99), respectively. Negative and positive predictive values were 97% (95% CI: 85-99), and 95% (95% CI: 83-99), respectively. The diagnostic accuracy was 96% (95% CI: 88-99). The likelihood ratio for a positive test was 17 and for a negative test was 0. CONCLUSIONS: Although the (13)C-UBT is the most accurate among the available noninvasive tests, our results show that an H. pylori stool test using monoclonal antibody might be an excellent alternative.     

Comparison of two different stool antigen tests for the primary diagnosis of Helicobacter pylori infection in turkish patients with dyspepsia

AIM: To assess the reliability of two different enzyme immunoassays in detecting the Helicobacter pylori status in stool specimens of Turkish patients with dyspepsia. MATERIALS AND METHODS: One hundred and fifty-one patients [74 with nonulcer dyspepsia (NUD), 64 with duodenal ulcer (DU) and 13 with gastric cancer] who were admitted to the endoscopy unit of Istanbul University, Cerrahpasa Medical Faculty for upper gastrointestinal endoscopy because of dyspepsia were enrolled in the study. Helicobacter pylori infection was confirmed in all patients by histology, rapid urease test and culture. A patient was classified as being H. pylori-positive if the culture alone or both the histology and the rapid urease test were positive and as negative only if all of these tests remained negative. Stool samples were obtained from patients to assess the reliability of a monoclonal (FemtoLab H. pylori) and a polyclonal (Premier Platinum HpSA) stool antigen test and to compare the diagnostic accuracies of these two tests. A chi2 test was used for statistical comparisons. RESULTS: Using cut-off values of 0.19 for FemtoLab H. pylori and 0.16 for Premier Platinum HpSA, the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were 93%, 90%, 98%, 68% and 93% for the monoclonal test and 84%, 67%, 94%, 40% and 81% for the polyclonal test, respectively. The sensitivity, specificity, negative predictive value and diagnostic accuracy of the monoclonal test were significantly greater than those of the polyclonal test (chi2 = 3.98; p < .05 for sensitivity and chi2 = 15.67; p = .000 for specificity, chi2 = 15.78; p = .000 for negative predictive value and chi2 = 6.37; p = .012 for diagnostic accuracy). The bacterial load did not affect the sensitivity of either test. CONCLUSIONS: The monoclonal FemtoLab H pylori test, using a cut-off 0.19, is a very sensitive, specific and easy to perform diagnostic tool for the primary diagnosis of H. pylori infection in Turkish patients with dyspepsia.     

Multicenter comparison of rapid lateral flow stool antigen immunoassay and stool antigen enzyme immunoassay for the diagnosis of Helicobacter pylori infection in children

BACKGROUND AND AIM: The stool antigen enzyme immunoassay (EIA) methods are widely used for diagnosing Helicobacter pylori infection. Recently, a novel, rapid stool antigen test, the lateral flow immunoassay (LFI) method, has been developed. The primary purpose of this study was to compare the EIA method with the LFI method for the diagnosis of H. pylori infection in children. MATERIALS AND METHODS: Stool specimens from children being evaluated for H. pylori infection were also examined using the LFI (ImmunoCard STAT! HpSA) and EIA methods (Premier Platinum HpSA). The sensitivity, specificity and accuracy of the test were based on the 13C-labeled urea breath test. RESULTS: One hundred and eighty-two children and adolescents, 3-17 years of age (mean 9.2 years), were studied. In addition, 29 patients who received eradication therapy were re-evaluated 2 or 3 months post-treatment. The 13C-labeled urea breath test was positive in 64 patients (35.2%). The sensitivity, specificity and accuracy of the LFI method were 90.6% (95% CI = 80.7-96.5%), 95.8% (92.1-99.4%), and 94.0% (90.5-97.4%), respectively and for the EIA method, sensitivity, specificity and accuracy were 96.8% (95% CI, 89.0-99.6%) and 99.2% (97.5-100%), and 98.3% (96.5-100%), respectively. There were no significant differences in results among the age groups 3-5, 6-10 and 11-17 years. As for the assessment of H. pylori eradication, the results of the LFI and EIA methods agreed with those of 13C-urea breath test in 27/29 and 29/29 patients, respectively. CONCLUSIONS: The LFI stool antigen method showed a good sensitivity, specificity and accuracy for diagnosing H. pylori infection in children. This novel method may be useful in clinical practice as an office-based test because it is rapid, reliable and easy to perform.     

The pathological examinations of gastric mucosa in patients with Helicobacter pylori-positive and -negative pernicious anemia

Background. The basic histopathological finding in gastric mucosa is chronic atrophic gastritis in patients with pernicious anemia.
Materials and Methods. We evaluated the frequency of Helicobacter pylori and pathological examinations of gastric mucosa in pernicious anemia (n = 30) by endoscopical findings and biopsy. The results were compared with gastric mucosa specimens of patients with H. pylori –positive nonulcer dyspepsia (n = 36) and H. pylori –negative nonulcer dyspepsia (n = 21).
Results. H. pylori was diagnosed in 12 patients (40%) with pernicious anemia. Fundal biopsy examinations showed atrophic gastritis in 30 patients (100%), intestinal metaplasia in 13 patients (43.3%), lymphoid follicle in 15 patients (50%), and dysplasia in 6 patients (20%). Antral biopsy examinations showed atrophic gastritis in 8 patients (26.6%), intestinal metaplasia in 8 patients (26.6%), lymphoid follicle in 8 patients (26.6%), and dysplasia in 3 patients (10%). The frequency of fundal inflammation, atrophy, intestinal metaplasia, lymphoid follicle, and dysplasia and antral intestinal metaplasia and mild antral dysplasia were found to be higher in those in the pernicious anemia group than in the nonulcer dyspeptic patients. Antral inflammation, atrophy, and moderate and severe antral dysplasia were found to be higher in those in the nonulcer dyspeptic group.
Conclusions. Particularly, fundal precancerous lesions were found to be more frequent in patients with pernicious anemia independent of H. pylori.     

慢性腹痛患儿C~(13)-尿素呼气试验与胃镜检查的临床意义

目的了解慢性腹痛患儿幽门螺杆菌(H.pylori)的感染状态及幽门螺杆菌感染患儿内镜下表现的特点。方法应用C13尿素呼气试验,对905例以慢性腹痛为主要症状的患儿进行检测,对C13呼气试验阳性者进行电子胃镜检查。结果905例慢性腹痛患儿中H.pylori呈阳性185例(20.44%),随年龄增长,其H.pylori阳性率升高,学年组已达高峰。对H.pylori阳性者进行胃镜检查结果显示十二指肠隆起病变47例占25.40%,结节性胃炎41例占22.1%,慢性浅表性`胃炎38例占20.5%,结节性胃炎伴十二指肠隆起病变23例占12.43%,十二指肠球部溃疡23例占12.4%。胃溃疡7例,占3.7%(其中包括1例复合性溃疡),结节性胃炎伴十二指肠炎6例,占3.2%。结论H.pylori感染为小儿慢性腹痛的主要原因之一,也是导致慢性胃炎及消化性溃疡的主要原因之一。C13尿素呼气试验方便,快速,无痛苦,无放射性,是一较好的H.pylori检测方法;对既有消化道症状同时C13呼气试验阳性者进行胃镜检查能够协助临床诊断及治疗。     

Comparison of stool antigen immunoassay and serology for screening for Helicobacter pylori infection in intellectually disabled children

Diagnosis of active Helicobacter pylori infection in intellectually disabled (ID) children is problematic because they are unable to cooperate with performance of invasive tests. In this study, the non‐invasive methods of measuring serum IgG antibody concentrations and performing stool antigen tests were used to screen for H. pylori infection in ID children. Eighty‐seven children with intellectual disabilities were studied. The amount of serum IgG antibody against H. pylori was measured by the ELISA method. Stool samples were examined using an amplified IDEIA HpStAR kit. To assess categorical variables, X², Fisher's exact and Kappa tests were used. The stool antigen tests showed that 93.1% of the children had H. pylori antigen and the serology test that 85.1% of children were positive for H. pylori IgG antibodies. Agreement between results of H. pylori stool antigen (HpSA) testing and IgG antibody serology was 82.8%; however, according to the kappa measure of agreement this agreement is not statistically significant (value, 0.128; P = 0.19). Discordant results were observed for 15 children (17.2%): 11 (12.6%) who were positive on HpSA test but negative by serology and 4 (4.6%) who were IgG seropositive but had negative HpSA tests. This study showed a notably higher rate of H. pylori infection in ID children than has been reported by others for non‐ID children from the same geographical area. The HpSA test is a valid method for primary screening for H. pylori infection in ID children; it detects the specific antigens shed during active infections and has less cross‐reactivity than serological tests that detect antibodies. HpSA is a sensitive non‐invasive method for detecting infection in ID children and may serve as an accurate alternative to serology.     

Helicobacter pylori colonization in the first 3 years of life in Japanese children

BACKGROUND: Acquisition of Helicobacter pylori infection occurs in early childhood, but the exact time of the acquisition and dynamics of infection are not clear. The aim of this study was to estimate the time of acquisition of H. pylori colonization in infants. SUBJECTS AND METHODS: This prospective follow-up study included 237 infants born in Wakayama Rosai Hospital from February, 2001 to April, 2002. Stool samples were collected at indicated ages, and H. pylori antigens were determined by a stool antigen test, HpSA. RESULTS: One-hundred and eight infants among initially enrolled 237 children have been followed up until 24 months. Among these, 16 infants turned to be HpSA positive within 12 months, but only four remained positive by the consecutive tests with optical density values of more than 0.7. They were assumed persistent positives. The rest 12 infants reverted to be negative by the consecutive tests and were assumed transient or false-positives. The optical density values of HpSA in the transient cases were exclusively less than 0.35. CONCLUSIONS: The consecutive follow up of HpSA, but not the one-point test, might be useful to diagnose persistent colonization of H. pylori in young infants, and some infants seemed to acquire H. pylori infection in the first year of life. These results should be taken into account for prevention and treatment strategies for H. pylori infection in infants.     

Long-term Administration of Probiotics to Asymptomatic Pre-school Children for Either the Eradication or the Prevention of Helicobacter pylori Infection

Background:  The role of probiotics in the armamentarium remains to be defined. The aims of this study were to investigate whether the long-time administration of Lactobacillus gasseri OLL2716 (LG21) strain can eradicate H. pylori in asymptomatic pre-school children and/or prevent H. pylori infection.
Methods: A total of 440 children, from 5–7 years of age, attending a kindergarten in Thailand were screened by the Helicobacter pylori stool antigen (HpSA) test. Thereafter 132 H. pylori positive and 308 H. pylori negative children were recruited to eradication and randomized prevention arms, respectively. Children in the active and placebo treatment groups received Lactobacillus gasseri OLL2716 (LG21) containing cheese and ordinary cheese, respectively, for 12 months. Eradication was defined as reversion by HpSA at 12 months. Prevention was defined as persistently HpSA negative at 12 months.
Results:  Eighty-two of 132 H. pylori positive (62%) completed the eradication arm, of which 24 (29.3%) were negative at 12 months according to the HpSA test. In the randomized prevention arm, 123 of 156 (79%) and 99 of 122 (81%) completed active and placebo arms, respectively, of which 4.1% and 8.1%, respectively, were HpSA positive at 12 months based on a per-protocol analysis ( p  = .21).
Conclusion: Further trials are needed.     

Evaluation of stool antigen test, PCR on ORAL samples and serology for the noninvasive detection of Helicobacter pylori infection in children

BACKGROUND: Endoscopy represents the gold standard for the diagnosis of Helicobacter pylori infection. We evaluated three noninvasive tests in a group of children: the immunoassay for detection of H. pylori stool antigen, the polimerase chain reaction for identification of bacterial DNA on the oral cavity and the serum specific antibodies. MATERIALS AND METHODS: One hundred and ninety children underwent endoscopy for various gastrointestinal symptoms. H. pylori stool antigen and anti-H. pylori antibodies were assayed by commercial kits. The bacterial DNA on saliva and oral plaque was detected by a seminested PCR. RESULTS: Based on the positivity of culture or urease rapid test and histology, infection was detected in 47 patients. The statistical analysis showed that, for the detection of the infection, stool antigen assay is more effective in sensitivity and negative predictive value (91.5% and 96.5%), whereas specificity and positive predictive values appear slightly better in serology (89.6% and 76.0%). Correlations between serum IgG both with patients' age (r = 0.21, p < .05) and H. pylori stool antigen (r = 0.47, p < .01) were found. The search for bacterial DNA on oral samples proved to be very specific (99.1% on saliva and 98.2% on plaque), but insensitive (22.2% and 25.7%). CONCLUSIONS. In children H. pylori stool antigen represents a sensitive test, suitable for detecting H. pylori infection. Serum IgG proved to be more specific; the PCR on the oral cavity resulted as being a very specific, but insensitive test.