Studies of 13C-urea breath test for diagnosis of Helicobacter pylori infection in Japan

In recent years Helicobacter pylori infection has been implicated in the etiology of a variety of upper gastrointestinal diseases. The aim of this multi-center trial was to search for the cut-off value of the simple ¹³C-urea breath test (¹³C-UBT) for diagnosis of H. pylori infection, and to examine the sensitivity and specificity of ¹³C-UBT for culture, the rapid urease test (CLO test), histology, and serological tests. Two hundred and forty-eight patients participated in this study after giving their informed consent. Endoscopic biopsy specimens were taken from gastric antrum and corpus for culture (190 patients), CLO test (222 patients), and histology (98 patients). A serological test was carried out for all patients. H. pylori infection was established when culture was positive or more than two of the tests, histology, CLO test, and serological test, were positive, and non-infection status was established when the all tests more than two tests were negative. After baseline breath samples were taken, the patients (who had fasted) were given 100 mg of ¹³C-urea in 100 ml water while sitting; they washed out the mouth with water. They were then placed in the left lateral decubitus position for 5 min, and additional breath samples were taken 10, 20, 30, 45, and 60 min after urea administration, with patients in the sitting position. One hundred and sixty-five of the 248 patients were infected, 48 were not infected, and H. pylori infection status was not evaluated in 35 by endoscopic and serological tests. Breath samples at 20 min were employed to determine the cut-off value. Using the receiver operating characteristic (ROC) curve, we determined the cut-off value for a positive UBT at 2.5 Δ‰. The sensitivities of UBT for culture, CLO test, histology, and serological test were 98.4%, 98.6%, 100.0%, and 92.5%, and the specificities were 78.8%, 82.5%, 83.3%, and 87.3%, respectively. The cut-off value of 13C-UBT for the diagnosis of H. pylori infection was 2.5 Δ‰; this test is a simple and non-invasive method for the diagnosis of this infection and has high sensitivity and specificity. Received Nov. 18, 1996; accepted June 20, 1997     

Capsule 13C-urea breath test for the diagnosis of Helicobacter pylori infection

AIM: To compare the accuracy of capsule 13C-urea breath test (UBT) with conventional invasive methods for the diagnosis of Helicobacter pylori infection. METHODS: One hundred patients received CLO test, histological examination, culture and 100- or 50-mg capsule UBT for the diagnosis of H pylori infection. H pylori infection was defined as those with positive culture or positive results from both histology and CLO test. RESULTS: Both the sensitivity and specificity of the 100-mg capsule UBT (n=50) were 100%. The sensitivity and specificity of the 50-mg capsule UBT (n = 50) were 96.4 and 100%, respectively. Taken together, the accuracy of capsule UBT (n =100) was higher than that of CLO test, histology and culture (100% vs 92%, 91% and 89%, respectively; P= 0.035, 0.018 and 0.005, respectively). Our data showed that the optimal timing of sampling for 100-and 50-mg capsule UBT was 15-30 and 6-15 min, respectively. CONCLUSION: Capsule UBT has a higher accuracy compared with biopsy-based tests. It is an ideal method for the diagnosis of H pylori infection.     

^13C—尿素呼气试验诊断幽门螺杆菌感染的研究

目的评估13C-尿素呼气试验（13C-UBT）幽门螺杆菌（Hp）感染的可靠性。方法对82例因胃病而行胃镜检查的患者，于胃窦和胃体取多个活检标本作组织学、粘膜涂片和快速尿素酶试验，以决定是否感染Hp，并作13C-UBT。结果13C-UBT的敏感性、特异性、阳性预测值、阴性预测值是与组织学和尿素酶方法检测Hp的检测结果比较而计算得到。13C-尿素呼气试验的敏感性97．92％、特异性100％、阳性预测值100％、阴性预测值97．14％、准确性98．78％。结论13C-尿素呼气试验有高度敏感性和特异性，对确定患者的Hp感染状态是一非常可靠而又无创伤的诊断方法。     

Simplified 13C-urea breath test with a new infrared spectrometer for diagnosis of Helicobacter pylori infection

BACKGROUND AND AIM: Infrared spectrometry has correlated excellently with mass spectrometry in detecting the ratio of 13CO(2) to 12CO(2) in breath samples. The present study aimed to evaluate the accuracy of the 13C-urea breath test (13C-UBT) using a new model of infrared analyzer. METHODS: A total of 600 patients who were undergoing upper endoscopy without receiving eradication therapy were entered into the study. Culture, histology, and rapid urease test on biopsies from the antrum and corpus of the stomach were used for the determination of Helicobacter pylori infection. Breath samples were collected before and 20 min after drinking 100 mg 13C-urea in 100 mL water. The optimal cutoff value was determined by the receiver operating characteristic curve. RESULTS: Of the 586 patients who were eligible for analysis, 369 were positive for H. pylori infection, 185 were negative for H. pylori infection, and 32 were indeterminate. When the appropriate cutoff value was set at 3.5 per thousand, a sensitivity of 97.8%, a specificity of 96.8% and an accuracy of 97.5% were obtained using the 13C-UBT. The accuracy of the 13C-UBT decreased when CO(2) concentration in the breath sample was <2%, as compared with > or = 2% (93.6%vs 97.7%), mainly because of a decrease in specificity (81.8%vs 97.7%). There were 2.7% of patients with Delta13CO(2) values that fell between 3.0-4.5 per thousand, in whom the risk of error was 47%. CONCLUSIONS: The 13C-UBT performed with infrared spectrometry is a highly sensitive, specific, and non-invasive method for the detection of H. pylori infection. The immediate availability of the test result and technical simplicity make it particularly effective in routine clinical practice.     

Appropriate cut-off value of 13C-urea breath test after eradication of Helicobacter pylori infection in Japan

BACKGROUND AND AIM: A cut-off value of 2.5 per thousand for the 13C-urea breath test (UBT) is recommended in Japanese persons, based on the result of a multicenter trial in patients prior to treatment for eradication of Helicobacter pylori. The cut-off value of 2.5 per thousand has also been used in the assessment of eradication after treatment. The 6-8-week evaluation after treatment is recommended in the guidelines of the Japanese Society of Gastroenterology. The present study aimed to prospectively re-assess the cut-off value of the 13C-UBT at 6 weeks after treatment by using the results obtained at 6 months as an indication of true positive or true negative H. pylori infection status. METHODS: One hundred and ninety patients who were positive for H. pylori underwent eradication treatment, and 177 patients of these patients who were assessed as having true positive or true negative H. pylori status at 6 months after treatment were evaluated in this study. Eradication was assessed by 13C-UBT, culture, and histology at 6 weeks and at 6 months after treatment, and the cut-off value of 13C-UBT at 6 weeks was re-assessed. RESULTS: A cut-off value of 3.5 per thousand. at 6 weeks after treatment showed 97.2% diagnostic accuracy, while a cut-off value of 2.5 per thousand at 6 weeks showed 96.0% diagnostic accuracy. For a 3.5 per thousand cut-off value, only five patients were positive by 13C-UBT and were negative by culture and histology at 6 weeks, and three patients were true positive and two were false positive by the 13C-UBT at 6 months. CONCLUSION: A cut-off value of 3.5 per thousand for the 13C-UBT is recommended at 6 weeks after eradication treatment in Japanese persons.     

A 13C-urea breath test in children with helicobacter pylori infection: assessment of eradication therapy and follow-up after treatment

Purpose. Our aim was to evaluate the usefulness of the ¹³C-urea breath test (UBT) for the diagnosis of Helicobacter pylori infection, for assessment of the efficacy of eradication therapy, and for post-treatment follow-up in children. Methods. Seventy-two patients who underwent endoscopy for symptoms related to the upper gastrointestinal tract were examined by rapid urease test, histology, and culture. The patients were also studied with serology and UBT. Results. Forty-seven of the 72 patients were diagnosed with H. pylori infection, based on the results of biopsy-based tests and serology. As an initial diagnostic test to detect H. pylori infection, the sensitivity of the UBT was 95%, which was comparable with that of histology (94%), rapid urease test (96%), and serology (91%) and was greater than that of culture (79%). The specificity of the UBT was 100%, which was comparable with that of the other four tests. The efficacy of eradication therapy was assessed by biopsy-based tests and the UBT in 24 H. pylori-positive patients. For this purpose, the sensitivities of UBT and histology were 100%, while the sensitivities of culture and the rapid urease test were 88%. The specificity was 100% for all of these tests. Eleven patients were assessed by biopsy-based tests and UBT after more than 6 months of post-treatment follow-up. There were no discordances between the results of the UBT and those of the biopsy-based tests in any of the patients. Conclusions. The UBT may be useful for detecting H. pylori infection in children with upper gastrointestinal tract symptoms, for assessment of the efficacy of eradication therapy, and for the follow-up evaluation of patients after the therapy. Received: November 24, 2000 / Accepted: March 30, 2001     

13C-urea breath test in the management of Helicobacterpylori infection.

The urea breath test is a noninvasive and very accurate test for the diagnosis of Helicobacter pylori infection. However, false negative urea breath test results have been reported to occur in a considerable percentage of the individuals taking proton pump inhibitors; the interval needed to be completely confident that false negative tests had been excluded has varied among the different studies between 6 and 14 days. The impact of H₂-receptor antagonists on the accuracy of urea breath test remains controversial, although, in contrast with proton pump inhibitors, the data suggest that H₂-receptor antagonists, for the most part, have little effect on the result of the urea breath test. The urea breath test does not represent a suitable tool for estimating the density of H. pylori colonization. The only quantitative information to be obtained from the urea breath test is that the higher the δ value, the lower the probability of a false-positive urea breath test result. Although some authors have demonstrated a correlation between urea breath test values and histological lesions of the gastric mucosa, the practical utility of this relationship remains unclear. It has been suggested that the pretreatment urea breath test has the potential to identify patients who require modification of the standard therapeutic regimen (for example, prolonging the duration of treatment or increasing the pharmacological dose when bacterial density is high), but other studies could not confirm this relationship. Some studies have shown that the urea breath test is less accurate in patients who have undergone partial gastrectomy. Finally, in contrast with biopsy-based methods, which are responsible for a high number of false-negative results when used to diagnose H. pylori infection in patients with upper gastrointestinal bleeding, urea breath test seems not to be negatively influenced by the presence of this complication.     

Delta (13)C-urea breath test value is a useful indicator for Helicobacter pylori eradication in patients with functional dyspepsia

BACKGROUND: Eradication of Helicobacter pylori is not routinely recommended for the symptomatic relief and the prevention of gastric cancer in patients with functional dyspepsia. The present study investigated a useful indicator of H. pylori eradication in such patients by determining the optimal cutoff value of a 13C-urea breath test (UBT). METHODS: One hundred dyspeptic patients participated in the study. Dyspepsia was scored, and a 13C-UBT administered. A level of delta 13C-UBT of>4 per thousand was diagnosed as H. pylori-positive. After the stomach was endoscopically sprayed with phenol red, biopsy specimens were taken from the antrum, body and cardia of the stomach for the assessment of H. pylori density, and activity (neutrophil infiltration) and degree (lymphocyte infiltration) of gastritis. RESULTS: Correlation between delta 13C-UBT and dyspepsia score was not found. Delta 13C-UBT significantly correlated with H. pylori density score in the total stomach (r = 0.53, P < 0.0001), neutrophil (r = 0.34, P = 0.0005) and lymphocyte score (r = 0.69, P < 0.0001). Twenty-six of the 100 subjects had a neutrophil score of >or=4, lymphocyte score of >or=4, and H. pylori score of >or=4. Their 95% confidence interval of mean was 58.2 per thousand, which reflects moderate to marked acute and chronic gastritis, and dense H. pylori colonization. CONCLUSIONS: The 13C-UBT is a reliable semiquantitative test to assess H. pylori density and the activity and degree of gastritis. It is proposed that H. pylori eradication therapy might be beneficial for patients with functional dyspepsia with a delta 13C-UBT of >58.2 per thousand.     

An optimized 13C-urea breath test for the diagnosis of H pylori infection

AIM： To validate an optimized ^13C-urea breath test （^13C-UBT） protocol for the diagnosis of H pylori infection that is cost-efficient and maintains excellent diagnostic accuracy.
METHODS： 70 healthy volunteers were tested with two simplified ^13C-UBT protocols, with test meal （Protocol 2） and without test meal （Protocol 1）. Breath samples were collected at 10, 20 and 30 rain after ingestion of 50 mg ^13C-urea dissolved in 10 mL of water, taken as a single swallow, followed by 200 mL of water （pH 6.0） and a circular motion around the waistline to homogenize the urea solution. Performance of both protocols was analyzed at various cut-off values. Results were validated against the European protocol.
RESULTS： According to the reference protocol, 65.7% individuals were positive for H pylori infection and 34.3% were negative. There were no significant differences in the ability of both protocols to correctly identify positive and negative H pylori individuals. However, only Protocol 1 with no test meal achieved accuracy, sensitivity, specificity, positive and negative predictive values of 100%. The highest values achieved by Protocol 2 were 98.57%, 97.83%, 100%, 100% and 100%, respectively.
CONCLUSION： A 10 min, 50 mg ^13C-UBT with no test meal using a cut-off value of 2-2.5 is a highly accurate test for the diagnosis of H pylori infection at a reduced cost.     

13C-urea breath test: reproducibility and association with the severity of Helicobacter pylori-associated antral gastritis

BACKGROUND: The purpose of the present paper was to assess the reproducibility of the (13)C-urea breath test ((13)C-UBT) and its ability to reflect the level of Helicobacter pylori-associated inflammation. METHODS: Asymptomatic H. pylori-positive subjects (n = 21) performed the (13)C-UBT six times. The H. pylori-positive symptomatic subjects (n = 55) performed the (13)C-UBT and had antral biopsies taken for histopathology, culture, urease activity assay and myeloperoxidase activity assay. RESULTS: No significant intraindividual variation in (13)C-UBT results were observed for the asymptomatic subjects. The (13)C-UBT results were significantly higher in symptomatic subjects with a moderate to severe gastritis compared to a mild gastritis and to no inflammation (34.5 +/- 4.4 vs 17.7 +/- 2.8 vs 1.7 +/- 0.1, respectively, P < 0.01). The (13)C-UBT results significantly correlated with urease (r = 0.55) and myeloperoxidase activity (r = 0.82) but not with bacterial load. conclusion: The (13)C-UBT is a reproducible determinant of H. pylori infection and non-invasively assesses the severity of antral inflammation.     

13C-尿素呼气试验对幽门螺杆菌密度及胃黏膜炎症的判断价值

目的 探讨６１３Ｃ尿素呼气试验（ＵＢＴ）对幽门螺杆菌（Ｈｐ）感染密度及胃黏膜炎症程度的判断价值。方法 以病理组织学为对照,分析ＵＢＴ对Ｈｐ诊断的准确性并比较不同细菌感染密度以及不同炎症细胞浸润程度时ＵＢＴ结果（ＤＯＢ值）的差异。结果 ＵＢＴ对Ｈｐ诊断的敏感性为９３．２％,特异性为８９．１％。Ｈｐ感染密度重度组的ＤＯＢ值显著高于轻中度组（Ｐ〈０．０５）,ＷＳ染色分级与ＤＯＢ值之间具有弱相关性（ｒｓ＝     

红外能谱测量法20mg酸化胶囊^13C-UBT的效能评价

目的探讨剂量小于常规75～100mg、红外能谱测量法^13C-尿素呼气试验（^13C-UBT）诊断幽门螺杆菌（H．pylori）感染的可行性。方法133例因消化不良进行胃镜检查的门诊患者,胃黏膜活检标本Giemsa染色检查H．pylori,红外能谱测量法进行20mg酸化胶囊^13C-UBT,分别应用ROC法和特异性优先法评价诊断效能。结果59例H．pylori阳性病人和74例阴性病人DOB值分别为5．27±4．49和-0．50±0．98,差异显著（P〈0．05）。ROC法的最适判别值为DOB=0．4时,其诊断敏感性、特异性和准确性分别为91．5％（54／59）、89．2％（66／74）和90．2％（120／133）;以特异性优先法的最适判别值为DOB=2．0时,其诊断敏感性、特异性和准确性分别86．4％（51／59）、100％（74／74）和94．0％（125／133）。结论红外能谱测量法小剂量^13C-尿素呼气试验是可行的,但20mg酸化胶囊^13C-尿素呼气试验方案尚不能满足临床诊断需要。     

Influence of urease activity in the intestinal tract on the results of 13C-urea breath test

Background and Aim: A late rise in ¹³CO2 excretion in the ¹³C‐urea breath test (UBT) should be found when the substrate passes rapidly through the stomach and makes contact with the colonic bacteria. The aim of this study was to evaluate the influence of intestinal urease activity on the results of the UBT. Method: A total of 143 subjects who were diagnosed as Helicobacter pylori negative by serology, histology and rapid urease test were recruited. At the end of endoscopy, the tip of the endoscope was placed to the second part of the duodenum and 20 mL of water containing 100 mg of ¹³C‐urea was sprayed into the duodenum. Breath samples were taken at baseline and at 5, 10, 20, 30 and 60 min after administration. Results: Of 143 subjects, breath Δ¹³CO2 values higher than 2.5‰ were detected in six (4.2%), four (2.8%) and five (3.5%) subjects at 20, 30 and 60 min, respectively. There was no subject with high Δ¹³CO2 values at 5 and 10 min. Only one subject had an immediate rise at 60 min. Conclusion: Variability derived from urease activity in the intestinal tract appears to be minimal up to 60 min after ingestion of the test urea.     

Comparison between a new 13C-urea breath test, using a film-coated tablet, and the conventional 13C-urea breath test for the detection of Helicobacter pylori infection

Background In Japan, urea breath-testing includes mouth rinsing with water immediately after the ingestion of ¹³C-urea solution, to prevent false-positive results that are caused by oral bacteria with urease activity. Our objective was to evaluate the diagnostic performance of a urea breath test using a film-coated ¹³C-urea tablet and omitting mouth rinsing.Methods The study was a multicenter trial comparing the solution- and tablet-based urea breath tests (UBTs). Helicobacter pylori status was determined by histology, culture, and rapid urease testing.Results Of the 255 subjects who completed the study, evaluation of the tablet-based UBT was possible in 254, and comparison of the tablet-based UBT and the solution-based UBT was possible in 250 patients. When the assessment achieved by a combination of biopsy-based methods was used as a reference standard, the sensitivity, specificity, and accuracy of the tablet-based method were determined to be 97.7%, 98.4%, and 98.0%, respectively. When the results of the solution-based UBT were used as a reference standard, the sensitivity, specificity, and accuracy of the tablet-based UBT were determined to be 96.9%, 97.6%, and 97.2%, respectively.Conclusions The ¹³C-urea tablet-based method proved to be a simple and accurate test for the diagnosis of H. Pylori infection. Mouth rinsing was not required.     

Simple and accurate 13C-urea breath test for detection of Helicobacter pylori in the remnant stomach after surgery

Background The efficacy of the ¹³C-urea breath test (UBT) for diagnosis of Helicobacter pylori (H. pylori) infection in the remnant stomach after surgery is a matter of controversy. We report a simple and accurate method of ¹³C-UBT for diagnosis of H. pylori infection in the remnant stomach after gastrectomy. Methods Eighty patients who had undergone gastrectomy with or without subsequent H. pylori eradication therapy were examined a total of 134 times for H. pylori infection by the ¹³C-UBT. ¹³C-Urea, 10mg per test, was used in powdered form or in the form of film-coated tablets. Breath samples were collected before and 10, 20, and 3min after ingestion. Mucosal biopsy specimens for bacterial culture and histological examination of the remnant stomach were collected endoscopically after each ¹³C-UBT test. Results Factors that confounded the ¹³C-UBT results in the remnant stomach were oral bacteria, posture, and residual food. Lying horizontally on the left side was the best position, and film-coated tablets indicated no necessity for use of mouthwash. The method of anastomosis had no significant effect on the results of the ¹³C-UBT. Thirty minutes and a cutoff of 4.5‰ were optimal conditions for detection of H. pylori in the remnant stomach. Under these conditions, sensitivity, specificity, and accuracy were 79.4% (27/34 cases), 95.7% (44/46 cases), and 88.8% (71/80 cases), respectively, in ordinary H. pylori diagnosis, and 100% (2/2 cases), 93.3% (14/15 cases), and 94.1% (16/17 cases), respectively, in evaluating eradication at 4 weeks after treatment of H. pylori. Conclusions Having the patient lie horizontally on the left side, using a film-coated ¹³C-urea tablet without using mouthwash, and measurement at 3min provided a simple and accurate method of ¹³C-urea breath test for detection of H. pylori in the remnant stomach after gastrectomy.     

More economic 25 mg 13C-urea breath test can be effective in detecting primary Helicobacter pylori infection in children

Background and Aim: The high cost of the ¹³C‐urea breath test (UBT) limits its wide application for both epidemiological and clinical studies for diagnosing Helicobacter pylori infection. This study examined if a lower‐dose UBT, applying 1 mg/kg of bodyweight (maximum 25 mg, UBT²⁵), could introduce cost savings while preserving high diagnostic yields for primary H. pylori infection. Methods: Children aged less than 16 years were recruited after obtaining consent. Those children with administration of antibiotics or proton pump inhibitors within 1 month of the tests were excluded. Positive tests for both the UBT with 50 mg urea (UBT⁵⁰) and the H. pylori stool antigen (HpSA) were qualifying criteria for H. pylori infection. Negative results for both indicated non‐infection. The UBT²⁵ was conducted 1 week after the UBT⁵⁰. The cut‐off points for the UBT²⁵ ranging from 2δ to 5δ were examined for their sensitivity, specificity and accuracy rates. Results: A total of 153 children were recruited (55% male; mean age 9.1 ± 3.5 years). Both the UBT⁵⁰ and HpSA test were positive in 18 (13.1%) and negative in 119 children, respectively. The sensitivity and specificity of the UBT²⁵ were optimally achieved at 88.9% (95% confidence interval [CI]: 71.4–100) and 95.0% (95% CI: 91.1–99.9), judged with a cut‐off point at 3.5δ. The diagnostic accuracy was significantly higher for children older than 7 years than for those younger than 7 years (98%vs 85%, P = 0.009). Conclusion: Lower‐dose UBT titration by bodyweight can cut costs while maintaining a highly reliable method to screen primary H. pylori infection in children older than 7 years, which is generally beyond school age.     

A combination of the Helicobacter pylori stool antigen test and urea breath test is useful for clinical evaluation of eradication therapy: a multicenter study

BACKGROUND: Helicobacter pylori stool antigen (HpSA) test is a new tool for evaluating the H. pylori infection. The present study was carried out to investigate the clinical usefulness of the HpSA test in the evaluation of eradication therapy by comparing it with the (13)C-urea breath test (UBT). METHODS: One hundred and five patients received eradication therapy for H. pylori. After more than 8 weeks, the success of the therapy was evaluated by the HpSA test and the UBT. Concordant results were regarded as a final diagnosis, but when the results were discordant, histological examination was carried out. RESULTS: Of the 105 patients receiving eradication therapy for H. pylori, 25 patients were regarded as H. pylori positive by the UBT and and 20 patients were regarded as H. pylori positive by the the HpSA test. Nine patients (8.6%) showed discordant results (seven cases with UBT(+) and HpSA(-), and two with UBT(-) and HpSA(+)). Five cases out of nine were ultimately judged as having a false-positive result of the UBT, and in these cases the UBT values were relatively low (below 10 per thousand). The final diagnostic accuracies of the UBT and the HpSA test were 94.3% (88.0-97.9%; 95% CI) and 97.1% (91.9-99.4%), respectively. When we used the HpSA test in cases with weakly positive UBT values, we were able to diagnose the correct status of H. pylori infection after eradication in 99% of all patients (94.8-100.0%). CONCLUSION: The HpSA test is a useful tool for the evaluation of eradication therapy and a combination of the HpSA test and UBT is clinically recommended.     

A Trial of 13C-urea Breath Test Combined with Endoscopic Phenol Red Test for Detection of Helicobacter pylori Infection

Abstract: Several tests for the diagnosis of Helicobacter pylori [H. pylori) infection have been employed in clinical studies. To minimize inaccuracies of these tests, we developed a new method which combines the ¹³C-urea breath test (UBT) with phenol red dye spraying endoscopy. We have designated this innovation the endoscopic ¹³C-urea breath test (EUBT). EUBT was conducted on 103 patients with gastroduodenal diseases. After the collection of a baseline breath sample, gastroduodenal endoscopy was performed. Twenty milliliters of 0.05% phenol red solution containing 100 milligrams of ¹³C-urea was sprayed onto the entire gastric mucosa. A breath sample was collected 15 minutes after spraying. We measured ¹³CO₂ in the breath samples by ratio mass spectrometry. Two biopsy specimens each from the antrum and the middle corpus were obtained for culture and histological examination. The mean EUBT values (±standard deviation) in H. pylori -positive and negative patients were 38.56±30.34%< and 0.19± 0.18%), respectively. The cut-off value for EUBT was 0.73%. The sensitivity and specificity of EUBT were 100% and 95.5%, as compared with culture, and 100% and 95.5%, as compared with histological evaluation. The EUBT value of the patients with the diffuse staining type (50.28±31.26%) was significantly higher than that of patients with the regional staining type (26.76±23.17%). EUBT is an accurate method of detecting H. pylori infection and a good indicator of the distribution of the infection within the stomach.     

幽门螺杆菌粪便抗原试验检测幽门螺杆菌感染的临床评价

目的 评价一种新的酶免疫法——幽门螺杆菌(HP)粪便抗原(HPSA)试验检测HP感染和监测HP根除治疗的可靠性。方法 未接受过抗HP治疗的患者分为2组，A组331例，无胃部手术史；B组65例，胃大部切除术后。2组患者因上消化道症状而接受胃镜检查，以胃黏膜活检标本快速尿素酶试验(RUT)和组织学检查(W-S染色)联合检测HP作为“金标准”，对HPSA试验的准确性进行评价，并与另一非侵入性的^13C-尿素呼气试验(^13C-UBT)加以比较。此外，A组中HP阳性的56例患者(C组)给予三联根除治疗1周，分别于停药后第1、7、14、21、28天收集粪便标本进行HPSA测定。于停药后第28天测定^13C-UBT，并以此为标准，评价HPSA试验的准确性。结果 A组患者经“金标准”诊断HP阳性175例，阴性156例。HPSA试验的敏感性为95，4％，特异性为91．0％，与^13C-UBT比较差异无统计学意义。B组患者中，经“金标准”诊断HP阳性30例，阴性35例。月psA试验敏感性为90．0％，^13C-UBT的敏感性为66．7％。HPsA试验的敏感性明显优于^13C-UBT(P＜0．05)。C组患者于停药后第28天经^13C-UBT诊断HP阳性16例，阴性40例。HPSA于停药后第1天54例阴性，此后随时间推移，未成功根除病例陆续转为阳性，而成功根除病例仍大部分保持在阴性范围，仅少数病例出现假阳性。停药后第28天的准确性最高(92．9％)。结论 HPSA试验是一种可靠的非侵入性检测方法，对于抗HP治疗前、后患者HP感染的诊断均有较高的准确性。对于胃大部切除术后的患者亦有较高的诊断价值。     

Endoscopic [13C]-urea breath test for quantification of Helicobacter pylori infection

BACKGROUND: We previously developed a new diagnostic method for Helicobacter pylori infection and called it the endoscopic [13C]-urea breath test (EUBT). Here we evaluate the relationship between the EUBT results and the histological findings. METHODS: The EUBT was performed on 137 patients with gastroduodenal diseases. After the collection of a baseline breath sample, gastroduodenal endoscopy was performed. Twenty milliliters of 0.05% phenol red solution containing 100 mg of [13C]-urea was sprayed over the entire gastric mucosa under endoscopic observation. A breath sample was collected 15 min after spraying. The content of 13CO2 in the breath samples was measured by ratio mass spectrometry. Two biopsy specimens each from the antrum and the middle corpus were obtained for culture and histology. Helicobacter pylori colonization, activity, inflammation, atrophy and intestinal metaplasia were classified on a four-point scale according to the Updated Sydney System. RESULTS: We found positive correlations between the EUBT values and the H. pylori colonization and activity score in the antrum and corpus, and negative correlations between the EUBT values and the atrophy and intestinal metaplasia scores in the corpus. CONCLUSIONS: The EUBT can be an indicator of the intragastric bacterial load and the histological findings for H. pylori.