• Title/Summary/Keyword: H. pylori urease

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Pathogenesis of Inflammation in H. pylori Infection

  • 정현채
    • 대한위암학회:학술대회논문집
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    • 2002.04a
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    • pp.9-17
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    • 2002
  • 위의 parietal cell 혹은 대식세포와 유사한 세포 내부에서 H. pylori가 발견된다는 보고가 있기는 하나 일반적으로 H. pylori는 Shigella와 같은 침습성 세균은 아닌 것으로 알려져 있다. 그럼에도 불구하고 H. pylori에 감염된 위점막에는 많은 수의 호중구를 위시한 염증세포의 침윤이 관찰되는데 H. pylori가 위상피세포에 부착 할 경우 위상피세포를 자극하여 interleukin-8을 위시한 cytokine 을 발현케하고 이에 의하여 호중구 등의 염증세포가 몰려들게 된다. 한편 고유층에 몰려든 호중구에서는 다시 interleukin-8을 위시한 일련의 호중구 활성화 chemokine을 분비하여 염증반응을 증폭해 나갈 것이다. 호중구에서 발현되는 myeloperoxidase나 활성 산소 등도 위점막의 조직 손상에 기여할 것이다. 위상피세포를 덮고 있는 점액층은 위상피세포를 보호한다고 알려져 있으나 H. pylori 감염의 경우 점액층에 의하여 H. pylori의 운동성이 증가하고 이것이 위상피세포로부터의 cytokine 발현을 자극하여 염증반응을 증폭하는데 관여할 가능성도 있다. H. pylori는 위상피세포에 대하여 apoptosis를 유도함과 동시에 고유층에 몰려든 호중구에 대하여는 apoptosis를 억제케하여 궁극적으로 염증반응을 증폭 및 지속시켜 나가는 쪽으로 작용한다. 한편 H. pylori는 위상피세포로부터 COX-2의 발현을 증가시키는데 이는 위상피세포의 apoptosis를 억제하는 방향으로 작용한다. 이외에 H. pylori의 urease에 의하여 발생한 암모니아나 H. pylori 자신이 분비하는 세포독소가 세포 손상을 유발할 가능성도 있다. 상술한 여러 독성 인자들 중 어느 하나가 단독으로 작용하기보다는 여러 인자가 같이 동시에 또는 시차를 두고 작용할 가능성이 많다고 생각된다.(\gamma-FeOOH)$, 침철광$(\alpha-FeOOH)$, 적금광$(\beta-FeOOH)$, 그리고 자철광$(Fe_3O_4)$이다. 인위적 부식에서는 전부 인철광의 부식물이 생성되었고 자연적 부식에서는 모두 침철광의 부식물이 생성되었다. 특히 철제 표면에 자연적으로 생성된 공식 녹을 XRD 분석한 결과 적금광으로 동정되었다. 이런 모든 시편들을 각 탈염방법에 따라 탈염처리한 후 XRD와 SEM-EDS으로 분석한 결과 인철광과 침철광은 어떠한 변화도 보이지 않았고, 다만 적금광으로 동정된 시편만이 잔존하지 않았다. 철기 제작별 $Cl^-$ 이온 추출량과 탈염효과에 대한 비교 실험은 이온 크로마토그래피 분석 결과와 마찬가지로 단조 철제유물이 주조 철제보다 $Cl^-$ 이온을 많이 가지고 있었으며, 탈염 처리 후에는 $Cl^-$ 이온은 전혀 발견되지 않았다. 이상의 결과 $K_2CO_3$와 Sodium 용액은 탈염처리에서 가장 적합한 탈염처리 용액으로 알수가 있었으며 특히 어떠한 탈염 용액으로 유물을 처리한다 해도 철제유물에 생성된 부식물은 제거되지 않는다는 것을 알게 되었다. 따라서 보존처리자는 유물 표면의 부식 상태만을 보고 처리하기 보다는 철기제작물로 고려하여 처리하는 것이 필요하다. 또한 금속에 부식을 야기시키는 $Cl^-$ 이온과 부식물을 완전하게 제거하여 탈염처리를 하는 것이 유물 부식을 최대한 지연시킬 수 있는 것이라 생각된다.TEX>$88\%$)였다.(P=0.063). 결론: 본 연구에서는 MTHFR C/T & T/T 유전자 다형성이 위암의 발생과 그 위치에 대해 관련이 있는 것으로 여겨지고, 흡연력, 음주력과는 관련이 없는 것으로 여겨진다.험이

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Predicting Helicobacter pylori infection from endoscopic features

  • Jun-young Seo;Ji Yong Ahn;Seonok Kim;Hee Kyong Na;Jeong Hoon Lee;Kee Wook Jung;Do Hoon Kim;Kee Don Choi;Ho June Song;Gin Hyug Lee;Hwoon-Yong Jung
    • The Korean journal of internal medicine
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    • v.39 no.3
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    • pp.439-447
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    • 2024
  • Background: Helicobacter pylori infection, prevalent in more than half of the global population, is associated with various gastrointestinal diseases, including peptic ulcers and gastric cancer. The effectiveness of early diagnosis and treatment in preventing gastric cancer highlights the need for improved diagnostic methods. This study aimed to develop a simple scoring system based on endoscopic findings to predict H. pylori infection. Methods: A retrospective analysis was conducted on 1,007 patients who underwent upper gastrointestinal endoscopy at Asan Medical Center from January 2019 to December 2021. Exclusion criteria included prior H. pylori treatment, gastric surgery, or gastric malignancies. Diagnostic techniques included rapid urease and 13C-urea breath tests, H. pylori culture, and assessment of endoscopic features following the Kyoto gastritis classification. A new scoring system based on endoscopic findings including regular arrangement of collecting venules (RAC), nodularity, and diffuse or spotty redness was developed for predicting H. pylori infection, utilizing logistic regression analysis in the development set. Results: The scoring system demonstrated high predictive accuracy for H. pylori infection in the validation set. Scores of 2 and 3 were associated with 96% and 99% infection risk, respectively. Additionally, there was a higher prevalence of diffuse redness and sticky mucus in cases where the initial H. pylori eradication treatment failed. Conclusions: Our scoring system showed potential for improving diagnostic accuracy in H. pylori infection. H. pylori testing should be considered upon spotty redness, diffuse redness, nodularity, and RAC absence on endoscopic findings as determined by the predictive scoring system.

Helicobacter pylori reinfection rate by a 13C-urea breath test and endoscopic biopsy tests in Korean children (한국 소아에서 Helicobacter pylori 박멸 후 13C-요소 호기 검사와 내시경적 생검을 이용한 재감염률 연구)

  • Shim, Jeong Ok;Seo, Jeong Kee
    • Clinical and Experimental Pediatrics
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    • v.49 no.3
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    • pp.268-272
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    • 2006
  • Purpose : The reinfection rate of H. pylori reported before $^{13}C$-urea breath test($^{13}C$-UBT) era was higher than that of the post $^{13}C$-UBT era. Children are usually reluctant to receive invasive endoscopic evaluation for the reinfection of H. pylori, particularly when they are asymptomatic. The aim of the study is to discover the reinfection rate by different diagnostic tests, and to find out what causes the difference. Methods : Children confirmed to be eradicated from H. pylori were included in the study. Reinfection was evaluated by endoscopic biopsy based tests(n=34, mean age $11.5{\pm}3.7$ years) and/or a $^{13}C$-UBT(n=38, mean age $10.0{\pm}3.6$ years) at the time of 18 months after eradication. At first visit, H. pylori infection had been diagnosed by positive results from a rapid urease test, Giemsa stain and Warthin-Starry stain and/or a positive culture. Eradication was defined as negative results from all above tests 1-3 months after eradication therapy. Results : Reinfection rate by endoscopic biopsy based tests was 35.3 percent(12/34). All patients had abdominal symptoms(P=0.000). Reinfection rate was 13.2 percent(5/38) by a $^{13}C$-UBT. Reinfection rate was higher in children with abdominal symptoms(P=0.008). There was no evidence that reinfection rate depended on the sex(P=0.694), age(P=0.827), diseases(peptic ulcers vs gastritis, P=0.730) and eradication regimen(P=0.087). Conclusion : Helocibacter pylori reinfection rate in Korean children was 13.2 percent per 18 months by a non-invasive test or $^{13}C$-UBT. Accurate determinations of the reinfection rate in children is affected by the compliance of the diagnostic tests. Non-invasive tests should be considered to investigate the reinfection rate in children.

Studies on the Mechanism of Action of the Gastric $H^{+}$+$K^{+}$ ATPase Inhibitor KH 3218

  • Cheon, Hyae-Cyeong;Kim, Hyo-Jung;Yum, Eul-Kgun;Cho, Sung-Yun;Kim, Do-Yeob;Yang, Sung-Il
    • Biomolecules & Therapeutics
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    • v.3 no.3
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    • pp.205-209
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    • 1995
  • The novel compound KH 3218 was synthesized and evaluated for its ability to inhibit the gastric H$^{+}$$K^{+}$ ATPase activity in vitro as well as to lessen gastric acid secretion in vivo. KH 3218 inhibited rabbit gastric H$^{+}$$K^{+}$ ATPase in a concentration and time dependent manner. $IC_{50}$/ value was estimated to be about 15 $\mu$M. The inhibition of the H$^{+}$$K^{+}$ ATPase by KH 3218 was blocked by sulfhydryl reducing agents, dithiothreitol or $\beta$-mercaptoethanol. The inhibition of the enzyme was not reversible by 50 fold dilution of the incubation mixtures, suggesting the irreversible nature of the inactivation. In the pylorus-ligated rift, KH 3218 reduced the total acid output as compared with the control. In addition, KH 3218 was capable of inhibiting H. pylori urease activity. These data suggest that KH 3218 is a potent inhibitor for H$^{+}$$K^{+}$ ATPase activity as well as for gastric acid secretion, and has a potential to be developed as a novel antiulcer agent.

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Influence of Helicobacter pylori Infection on Gastric Motility in Children and Adolescents with Functional Dyspepsia (기능성 소화불량 소아청소년에서 위 운동에 대한 Helicobater pylori 감염의 영향)

  • Ryoo, Eell;Nam, Yoo-Nee;Kweon, Chang-Kyu;Kang, Sung-Kil;Cho, Kang-Ho;Son, Dong-Woo;Tcha, Hann
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.12 no.2
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    • pp.133-139
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    • 2009
  • Purpose: In spite of many reports about Helicobacter pylori infection in children with functional gastrointestinal disorders, there are few reports about the influence of H. pylori infection to functional dyspepsia and gastric motility. Therefore, we studied the influence of H. pylori infection on gastric myoelectrical activity in children with functional dyspepsia. Methods: Between August 2006 and December 2008 upper gastrointestinal endoscopies with biopsies, the rapid urease test and/or $^{13}C$ urea breath test, and electrogastrography (EGG) were performed on 63 patients with histologic chronic gastritis; patients with chronic disorders were excluded. Comparisons about gastric myoelectrical activities were made between H. pylori-positive children (n=25) and H. pylorinegative children (n=38). Results: The percentage of pre- and post-prandial normogastria was relatively lower in H. pylori-positive children than H. pylori-negative children (80% vs. 65%, and 80% vs. 68%, respectively). Compared to H. pylori-negative children, H. pylori-positive children had lower postprandial predominant power (8.18${\pm}$22.36 dB and 32.20${\pm}$24.18 dB, respectively; p<0.01) and a lower power ratio (${\delta}P$; -1.28${\pm}$6.18 vs. +4.62${\pm}$5.93, respectively; p<0.01). Conclusion: It was suggested that the gastric myoelectrical activity in children with chronic gastritis can be influenced by H. pylori infection. Thus, this study indicates that H. pylori infection may be predictable in children with functional dyspepsia through analyzing the EGG parameters, and treatment may be considered in H. pylori-positive children with impaired gastric activity, especially in the lower prevalence area.

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Plumbagin Inhibits Expression of Virulence Factors and Growth of Helicobacter pylori (Plumbagin에 의한 헬리코박터 파이로리균의 성장 및 병원성 인자 발현 억제효과)

  • Lee, Min Ho;Woo, Hyun Jun;Park, Min;Moon, Cheol;Eom, Yong-Bin;Kim, Sa-Hyun;Kim, Jong-Bae
    • Microbiology and Biotechnology Letters
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    • v.44 no.2
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    • pp.218-226
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    • 2016
  • Helicobacter pylori primarily colonizes the human stomach. Infection by this bacterium is associated with various gastric diseases, including inflammation, peptic ulcer, and gastric cancer. Although there are antibiotic regimens for the eradication of H. pylori, the resistance of this species against antibiotics has been continuously increasing. The natural compound plumbagin has been reported as an antimicrobial and anticancer molecule. In this study, we analyzed the inhibitory effect of plumbagin on H. pylori strain ATCC 49503 as well as the expression of various molecules associated with H. pylori growth or virulence by immunoblotting and reverse transcription polymerase chain reaction (RT-PCR) analyses. We demonstrated the minimal inhibitory concentration of plumbagin on H. pylori through the agar dilution and broth dilution methods. Furthermore, we investigated the effect of plumbagin treatment on the expression of the RNA polymerase subunits and various virulence factors of H. pylori. Plumbagin treatment decreased the expression of RNA polymerase subunit alpha (rpoA), which is closely associated with bacterial survival. Moreover, the mRNA and protein levels of the major CagA and VacA toxins were decreased in plumbagintreated H. pylori cells. Likewise, the expression levels of urease subunit alpha (ureA) and an adhesin (alpA) were decreased by plumbagin treatment. Collectively, these results suggest that plumbagin may inhibit the growth, colonization, and pathogenesis of H. pylori by the mechanism demonstrated in this study.

Effect of Hot Water Extract of Alnus japonica Steud on the Experimentally-induced Acute Gastritis and Peptic Ulcers in Rats (오리나무 열수 추출물이 실험적으로 유발된 흰쥐의 위염 및 위궤양에 미치는 영향)

  • Na, Chun-Soo;Lee, Sang-Bum;Kim, Jin-Bum;Chung, Ha-Sook;Dong, Mi-Sook
    • Korean Journal of Pharmacognosy
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    • v.43 no.1
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    • pp.72-78
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    • 2012
  • Alnus japonica Steud (A. japonica) have long been used in the traditional medicine for gastric disorder, hepatitis and fatty liver in Korea. Antiulcer effects of A. japonica hot water extract (AJ ext) were evaluated by in vitro antibacterial activity against H. pylori, by the inhibitory action against the in vitro gastric $H^+/K^+$-ATPase and using rat models of gastric mucosal damage and gastric ulcer induced by HCl-ethanol, indomethacin, and restraint and water-immersion stress. For the determination of antibacterial activity of AJ ext against H. pylori, the activity of urease which released from H. pylori was measured in culture. AJ ext showed weak antibacterial activity against H. pylori with the growth inhibitions of 37% and 61% by adding final concentrations of 500 and $1000{\mu}g/ml$ culture, respectively at 24 h. To observe the inhibitory activity of AJ ext against the $H^+/K^+$-ATPase in hog gastric membrane vesicle, $IC_{50}$ value of AJ ext was $806.3{\mu}g/ml$. Pretreatment of AJ ext (200, 500 mg/kg, p.o.) prevented in a dose-dependent manner the acute gastritis in HCl-ethanol model and the formation of gastric ulcer in indomethacin model and restraint and water-immersion stress model. These results suggest that the AJ ext can be used for prevention and treatment of gastric mucosal damage and ulcers induced by various stress.

Seven-Day Bismuth-based Quadruple Therapy as an Initial Treatment for Helicobacter pylori Infection in a High Metronidazole Resistant Area

  • Vilaichone, Ratha-korn;Prapitpaiboon, Hatainuch;Gamnarai, Pornpen;Namtanee, Juraiwan;Wongcha-um, Arti;Chaithongrat, Supakarn;Mahachai, Varocha
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.14
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    • pp.6089-6092
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    • 2015
  • Background: The prevalence of metronidazole-resistant H. pylori is almost 50% in Thailand which severely limits the use of this drug for eradication therapy. The aims of this study were to evaluate the efficacy and safety profiles of 7-day bismuth-based quadruple therapy including metronidazole as an initial treatment for H. pylori infection in a high metronidazole resistance area. Materials and Methods: This study was performed at Thammasat University Hospital and King Chulalongkorn Memorial Hospital during January 2009 to October 2010. Patients with non-ulcer dyspepsia (NUD) with active H. pylori infection were assigned to receive seven days of quadruple therapy (pantoprazole 40 mg bid, bismuth subsalicylate 1,048 mg bid, amoxicillin 1 gm bid and metronidazole 400 mg tid). H. pylori infection was defined as positive H. pylori culture or two positive tests (rapid urease test and histology). Antibiotic susceptibility test for metronidazole by Epsilometer test (E-test) was performed in all positive cultures. At least four weeks after treatment, $^{13}C$ urea breath test ($^{13}C-UBT$) was performed to confirm H. pylori eradication. Results: A total of 114 patients were enrolled in this study, 50 males and 64 females with a mean age of 49.8 years. All 114 patients had a diagnosis of NUD. Overall eradication as confirmed by negative $^{13}C-UBT$ was achieved in 94 out of 114 patients (82.5%). 44 patients had positive cultures and success for E-test. In vitro metronidazole resistance was observed in 22/44 (50%) patients. Eradication rate in patients with metronidazole resistant strains was 16/22 (72.7%) and 20/22 (90.1%) with metronidazole sensitive strains (72.7% vs 90.1%, p-value=0.12; OR=3.75 [95%CI=0.6-31.5]). Minor adverse reactions included nausea, bitter taste, diarrhea and black stools but none of the patients dropped out from the study. Conclusions: Initial treatment with 7-day bismuth-based quadruple therapy including metronidazole, amoxycillin and pantoprazole is highly effective and well tolerated for metronidazole-sensitive H. pylori infections. However, the efficacy markedly decline with metronidazole resistance. Longer duration of this regimen might be required to improve the eradication rate and larger multi-center studies are needed to confirm this hypothesis.

Can the C-14 Urea Breath Test Reflect the Extent and Degree of Ongoing Helicobacter pylori Infection? (C-14 요소호기검사의 정량치가 Helicobacter pylori 감염 정도를 반영할 수 있을까?)

  • Lim, Seok-Tae;Sohn, Myung-Hee;Lee, Seung-Ok;Lee, Soo-Teik;Jeong, Myoung-Ja
    • The Korean Journal of Nuclear Medicine
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    • v.35 no.1
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    • pp.61-68
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    • 2001
  • Purpose: The C-14 urea breath test (C-14 UBT) is the most specific noninvasive method to detect Helicobacter (H) pylori infection. We investigated if the C-14 UBT can reflect the presence and degree of H. pylori detected by gastroduodenoscopic biopsies (GBx). Materials and methods: One hundred fifty patients (M:F=83:67, age $48.6{\pm}11.2$ yrs) underwent C-14 UBT, rapid urease test (CLO test) and GBx on the same day. For the C-14 UBT, a single breath sample was collected at 10 minutes after ingestion of C-14 urea (137 KBq) capsule and counting was done in a liquid scintillation counter for 1 minute, and the results were classified as positive (${\geq}200dpm$), Intermediate ($50{\sim}199dpm$) or negative (<50 dpm). The results of CLO tests were classified as positive or negative according to color change. The results of GBx on giemsa stain were graded 0 (normal) to 4 (diffuse) according to the distribution of H. pylori by the Wyatt method. We compared C-14 UBT results with GBx grade as a gold standard. Results: In the assessment of the presence of H. pylori infection, the C-14 UBT global performance yielded sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of 92.5%, 88.4%, 97.1%, 88.4% and 91.3%, respectively. However, the CLO test had sensitivity, specificity, PPV, NPV and accuracy of 83.2%, 81.4%, 91.8%, 81.4% and 82.7%, respectively. The quantitative values of the C-14 UBT were $45{\pm}27$ dpm in grade 0, $707{\pm}584dpm$ in grade 1, $1558{\pm}584dpm$ in grade 2, $1851{\pm}604dpm$ in grade 3, and $2719{\pm}892dpm$ in grade 4. A significant correlation (r=0.848, p<0.01) was found between C-14 UBT and the grade of distribution of H. pylori infection on GBx with giemsa stain. Conclusion: We conclude that the C-14 UBT is a highly accurate, simple and noninvasive method for the diagnosis of ongoing H. pylori infection and reflects the degree of bacterial distribution.

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Comparison of the Quantitative Values of C-14 and C-13 UBT to Reflect the Presence and Degree of Ongoing Helicobacter pylori Infection (Helicobacter pylori 감염 유무와 정도 반영에 대한 C-14와 C-13 요소호기검사 정량치 비교)

  • Lim, Seok-Tae;Kim, Dong-Wook;Jeong, Hwan-Jeong;Sohn, Myung-Hee
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.3
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    • pp.229-234
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    • 2008
  • Purpose: A urea breath test (UBT) using C-14 or C-13 has been developed for identifying Helicobacter (H) pylori infection on the basis of urease production with release of labeled $CO_2$. We investigated if the C-14 and C-13 UBT have the difference to reflect the presence and degree of H. pylori infection detected by gastro-duodenoscopic biopsies (CBx) in the same patients. Materials and methods: Thirty eight patients (M:F = 28:10, age $53.4{\pm}13.0$ yrs) with upper gastrointestinal symptoms such as indigestion, gastric fullness or pain consecutively underwent C-14 UBT, GBx and C-13 UBT within one week before medications. For the C-14 UBT, a single breath sample was collected at 10 minutes after ingestion of C-14 urea (37 KBq) capsule and counting was done in a liquid scintillation counter for 1 minute, and the results were classified as positive (${\ge}$ 200 dpm), intermediate (50-199 dpm) or negative (50 dpm). For the C-13 UBT, the results were classified as positive (${\ge}2.5\%_{\circ}$) or negative ($<2.5\%_{\circ}$). The results of GBx with Giemsa stain were graded 0 (normal) to 4 (diffuse) according to the distribution of H. pylori by the Wyatt method. We compared C-14 UBT and C-13 UBT results with GBx grade as a gold standard. Results: The prevalence of H. pylori infection by GBx with Giemsa stain was 25/38 (65.8%). In the assessment of the presence of H. pylori infection, the C-14 UBT global performance yielded sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of 92.0%, 92.3%, 95.8%, 91.7% and 92.1%, respectively. However, the C-13 UBT had sensitivity, specificity, PPV, NPV and accuracy of 96.0%, 84.6%, 92.3%, 91.7% and 92.1%, respectively. The more significant correlation in C-14 than C-13 UBT (r=0.948 vs r=0.819, p <0.001) was found between the value of UBT and the grade of distribution of H. pylori infection. Conclusion: We conclude that the diagnostic performance between C-14 and C-13 UBT to detect H. pylori infection is not significantly different, but the value of C-14 UBT more significantly reflects the degree of bacterial distribution.