Helicobacter pylori reinfection rate and duodenal ulcer recurrence in Korea

Recurrence of Helicobacter pylori following successful eradication and clinical outcomes in Korean patients

BACKGROUND/AIMS

Helicobacter pylori (H. pylori) infections can recur as either recrudescence or reinfection. At a time when the decline in the eradication rate is becoming evident, increases in the rate of recurrence are concerning. In addition, there are no guidelines for selecting an eradication regimen for H. pylori recurrence.

MATERIALS AND METHODS

A total of 996 H. pylori-infected patients treated with proton-pump inhibitor-based triple eradication therapy between 2017 and 2022 were enrolled in the study, and successful eradication therapies were confirmed by the 13 C-urea breath test. When retested within 1 year after successful eradication, analysis related to recrudescence was performed, and when retested after 1 year, analysis related to reinfection was performed. We reviewed the medical records and treatment outcomes of patients with H. pylori reinfection after successful eradication.

RESULTS

The recrudescence rate was 3.9% (9/228), and the reinfection rate was 3.7% (36/970 person-year). The frequency of reinfection reached 5.9% per person-year within the first 24 months and 2.0%-2.4% per person-year thereafter. In multivariate factor analysis, reinfection was significantly higher in patients with non-ulcer dyspepsia (p < 0.01). At first-line therapy for reinfection, the eradication rate of standard triple therapy (STT) was 50.0% (16/32). The eradication rate of second-line bismuth quadruple therapy was 81.3% (13/16), and levofloxacin-based rescue therapy was 66.7% (2/3).

CONCLUSION

Re-treatment of patients with H. pylori reinfection with STT had limited efficacy. Prospective research is needed to determine whether patients with non-ulcer dyspepsia are vulnerable to reinfection.

Systematic review with meta-analysis: the global recurrence rate of Helicobacter pylori

BACKGROUND

Up-to-date information regarding the recurrence rate of Helicobacter pylori (H. pylori) after eradication therapy is not available.

AIM

To evaluate the global recurrence rate following H. pylori eradication therapy and confirm its association with socioeconomic and sanitary conditions.

METHODS

A systematic search of PubMed, EMBASE and the Cochrane library was performed to identify potentially relevant publications using the following keywords: "Helicobacter pylori" or "H. pylori" or "Hp" and "recurrence" or "recrudescence" or "reinfection" or "recurrent" or "recurred" or "re-infect*" or "relapse*."

RESULTS

A total of 132 studies (53 934 patient-years) were analysed. Each study was weighted according to the duration of patient-years. The global annual recurrence, reinfection and recrudescence rate of H. pylori were 4.3% (95% CI, 4-5), 3.1% (95% CI, 2-5) and 2.2% (95% CI, 1-3), respectively. The H. pylori recurrence rate was inversely related to the human development index (HDI) (ie, 3.1% [95% CI, 2-4], 6.2% [95% CI, 4-8] and 10.9% [95% CI, 6-18] in countries with a very high, high and medium or low HDI) (P <.01) and directly related to H. pylori prevalence (10.9% [95% CI, 7-16], 3.7% [95% CI, 3-5], 3.4% [95% CI, 2-5] and 1.6% [95% CI, 0.5-3] in countries with a very high, high, medium or low local H. pylori prevalence) (P <.01). Global recurrence rates remained relatively stable between 1990s, 2000s and 2010s but varied across different regions (P <.05).

CONCLUSIONS

H. pylori recurrence remains a problem closely associated with socioeconomic and sanitary conditions. Methods to reduce recurrence in developing countries are needed.

[Peptic Ulcer Disease Associated with Helicobacter pylori Infection]

Although the global prevalence of peptic ulcer disease (PUD) is decreasing, PUD is still one of the most common upper gastrointestinal diseases in the world due to Helicobacter pylori infection and increased use of non-steroidal anti-inflammatory drugs. In Korea, the prevalence of H. pylori infection is also declining, but it is still the major cause of PUD. The outcomes of H. pylori infection are caused by imbalances between bacterial virulence factors, host factors, and environmental influences. In this review, we describe the prevalence trends of H. pylori infection in Korea, the mechanism of H. pylori infection-related PUD, and treatment strategies.

Periodontal therapy as adjunctive treatment for gastric Helicobacter pylori infection

BACKGROUND

Helicobacter pylori is estimated to affect about half the world's population and is considered as the main cause of chronic gastritis and peptic ulcer disease. Eradication of H. pylori infection accelerates ulcer healing and prevents relapse, reducing incidence of H. pylori-related gastric diseases. Numerous studies have provided evidence that the oral cavity could be a potential reservoir for H. pylori. The presence of oralH. pylori might affect the efficiency of eradication therapy and act as a causal force for its recurrence. Conversely, other investigators have indicated that the colonization and growth of H. pylori differs between the oral cavity and the stomach. Considering the open debate on the topic, it's necessary to clarify whether periodontal therapy is an effective adjunctive treatment for gastric H. pylori infection.

OBJECTIVES

To assess the effects of periodontal therapy plus eradication therapy versus eradication therapy alone for gastric H. pylori infection. The secondary objective is to compare the non-recurrence rate at long-term follow up in different treatment groups.

SEARCH METHODS

We identified randomized controlled trials (RCTs) by searching the Cochrane Central Register of Controlled Trials (CENTRAL) (2015, Issue 8), MEDLINE (1946 to August 2015), EMBASE (1980 to August 2015), and the Chinese Biomedical Database (1978 to August 2015). We also searched both ClinicalTrials.gov and the WHO ICTRP portal in October 2015. We handsearched the reference lists of included studies to identify relevant trials.

SELECTION CRITERIA

RCTs comparing periodontal therapy plus eradication treatment with eradication treatment alone, regardless of language of publication.

DATA COLLECTION AND ANALYSIS

Two reviewers selected the trials that met the inclusion criteria and extracted the details of each study independently. The data were pooled using both fixed-effect and random-effects models and results calculated as odds ratios (OR) with their 95% confidence intervals (CIs) based on an intention-to-treat analysis. However, because there was little difference in the results from these two models, we only reported the results from the fixed-effect model.

MAIN RESULTS

We included seven small RCTs involving 691 participants aged 17 to 78 years in our meta analyses. The primary result showed that periodontal therapy combined with H. pylori eradication treatment increased the eradication rate of gastric H. pylori compared with eradication treatment alone (OR 2.15; 95% CI 1.47 to 3.14; P < 0.0001) in people with H. pylori infection. In addition, periodontal therapy also had benefits on long-term gastric H. pylori eradication. After eradication of H. pylori, the non-recurrence rate of gastric H. pylori infection increased in participants treated with periodontal therapy compared with those who received eradication therapy alone (OR 3.60; 95% CI 2.11 to 6.15; P < 0.00001). According to the GRADE approach, the overall quality of the evidence was 'moderate' for eradication rate of gastric H.pylori and 'low' for non-recurrence rate of gastric H. pylori.

AUTHORS' CONCLUSIONS

Overall, periodontal therapy could increase the efficiency of H. pylori eradication and the non-recurrence rate of gastricH. pylori. In view of the limited number and quality of included studies, it will be necessary to conduct more well-designed, multicenter, and large-scale RCTs to determine the effects of periodontal therapy in eradicating gastric H. pylori and suppressing the recurrence of this bacterium in the stomach.

Periodontal therapy as adjunctive treatment for gastric Helicobacter pylori infection

BACKGROUND

Helicobacter pylori is estimated to affect about half the world's population and is considered as the main cause of chronic gastritis and peptic ulcer disease. Eradication of H. pylori infection accelerates ulcer healing and prevents relapse, reducing incidence of H. pylori-related gastric diseases. Numerous studies have provided evidence that the oral cavity could be a potential reservoir for H. pylori. The presence of oralH. pylori might affect the efficiency of eradication therapy and act as a causal force for its recurrence. Conversely, other investigators have indicated that the colonization and growth of H. pylori differs between the oral cavity and the stomach. Considering the open debate on the topic, it's necessary to clarify whether periodontal therapy is an effective adjunctive treatment for gastric H. pylori infection.

OBJECTIVES

To assess the effects of periodontal therapy plus eradication therapy versus eradication therapy alone for gastric H. pylori infection. The secondary objective is to compare the non-recurrence rate at long-term follow up in different treatment groups.

SEARCH METHODS

We identified randomized controlled trials (RCTs) by searching the Cochrane Central Register of Controlled Trials (CENTRAL) (2015, Issue 8), MEDLINE (1946 to August 2015), EMBASE (1980 to August 2015), and the Chinese Biomedical Database (1978 to August 2015). We also searched both ClinicalTrials.gov and the WHO ICTRP portal in October 2015. We handsearched the reference lists of included studies to identify relevant trials.

SELECTION CRITERIA

RCTs comparing periodontal therapy plus eradication treatment with eradication treatment alone, regardless of language of publication.

DATA COLLECTION AND ANALYSIS

Two reviewers selected the trials that met the inclusion criteria and extracted the details of each study independently. The data were pooled using both fixed-effect and random-effects models and results calculated as odds ratios (OR) with their 95% confidence intervals (CIs) based on an intention-to-treat analysis. However, because there was little difference in the results from these two models, we only reported the results from the fixed-effect model.

MAIN RESULTS

We included seven small RCTs involving 691 participants aged 17 to 78 years in our meta analyses. The primary result showed that periodontal therapy combined with H. pylori eradication treatment increased the eradication rate of gastric H. pylori compared with eradication treatment alone (OR 2.15; 95% CI 1.47 to 3.14; P < 0.0001) in people with H. pylori infection. In addition, periodontal therapy also had benefits on long-term gastric H. pylori eradication. After eradication of H. pylori, the non-recurrence rate of gastric H. pylori infection increased in participants treated with periodontal therapy compared with those who received eradication therapy alone (OR 3.60; 95% CI 2.11 to 6.15; P < 0.00001). According to the GRADE approach, the overall quality of the evidence was 'moderate' for eradication rate of gastric H.pylori and 'low' for non-recurrence rate of gastric H. pylori.

AUTHORS' CONCLUSIONS

Overall, periodontal therapy could increase the efficiency of H. pylori eradication and the non-recurrence rate of gastricH. pylori. In view of the limited number and quality of included studies, it will be necessary to conduct more well-designed, multicenter, and large-scale RCTs to determine the effects of periodontal therapy in eradicating gastric H. pylori and suppressing the recurrence of this bacterium in the stomach.

Helicobacter pylori recurrence after first- and second-line eradication therapy in Korea: the problem of recrudescence or reinfection

BACKGROUND

Recurrence of Helicobacter pylori (H. pylori) infection is the result of either recrudescence or reinfection. Annual recurrence rates per patient-year of follow-up have been reported to vary across countries. The aim of this study was to analyze recurrence rates of H. pylori after first-line and second-line eradication therapies in Korea.

MATERIALS AND METHODS

From 2007 to 2010, 2691 patients with H. pylori infection received first-line therapy and 573 patients who failed to respond to first-line therapy received second-line therapy. H. pylori infection and the success of eradication were assessed by endoscopic biopsy and rapid urease test or (13) C-urea breath test. All patients were advised to undergo (13) C-urea breath test or esophagogastroduodenoscopy with biopsy or rapid urease test 6 months after eradication, with annual follow-up thereafter.

RESULTS

The eradication rate of the first-line therapy was 79.9% (1283/1605) and that of the second-line therapy was 90.4% (394/436) by per protocol analysis. Annual recurrence rates sharply declined after 2-year follow-up. Annual recurrence rates within and after 2-year follow-up were 9.3 and 2.0% after first-line therapy and those of second-line therapy were 4.5 and 2.9%, respectively.

CONCLUSIONS

Annual recurrence rates of H. pylori showed a sharp decline after 2-year follow-up after eradication in Korean adults, which is not higher than that of Western countries. Enough time interval after treatment (i.e., 2 years) is necessary to confirm eradication, and it would not be easy to distinguish between recurrence and recrudescence before 2 years without identifying H. pylori strains.

Prevalence of Helicobacter pylori and its recurrence after successful eradication in a developing nation (Morocco)

INTRODUCTION

In developed countries, reinfection after successful eradication of Helicobacter pylori appears unusual. High prevalences of H. pylori in developing countries may result in high reinfection rates. In Morocco, published studies regarding the prevalence of H. pylori are limited, and to our knowledge, there are no data regarding the reinfection rate of H. pylori after successful treatment.

AIM

The aim of this study was to determine the prevalence of H. pylori in our area, and the reinfection rate at 6 months and 1 year of follow-up after successful eradication.

METHODS

Consecutive patients with investigated ulcer or non-ulcer dyspepsia were prospectively enrolled in the Hassan II University Hospital of Fez. Patients with H. pylori infection were treated with a 1-week triple therapy or 10 day sequential therapy. Those tested urea breath test negative after 3 months of treatment were followed prospectively with repeated urea breath test at 6 months and 1 year. H. pylori status at endoscopic examination was determined by rapid urease test, histology, and culture.

RESULTS

Four hundred and twenty-nine patients were enrolled in the study, among them 324 patients (75.5%) presented with H. pylori infection. Two hundred and fifty-six (83.3%) patients had successfully eradicated H. pylori following treatment, among them, two patients (0.8%) were reinfected with H. pylori over 12 months. The rate of reinfection was 0.42% in the first 6 months and of 0.45% in the first year of the study.

CONCLUSION

The results of the present study demonstrate that firstly, prevalence of H. pylori is high (75.5%) in our area, secondly as in developed countries, there is a low (0.8%) but continuous risk of H. pylori infection in adulthood. A different approach for follow-up after H. pylori eradication is probably needed in patients of developing countries, since reinfection prevalence is different between countries.

Long-term follow-up Helicobacter pylori reinfection rate and its associated factors in Korea

BACKGROUND

The reinfection rate of Helicobacter pylori has been reported to be low in developed countries but high in developing countries. The aim of this study is to evaluate the long-term reinfection rate of H. pylori and to investigate its associated risk factors in South Korea.

METHODS

During 2003-2010, H. pylori-positive 970 patients received standard proton pump inhibitor (PPI)-based triple eradication therapy, and follow-up H. pylori tests were performed with (13) C urea breath test or invasive tests (Giemsa histology, CLO test, and culture) 4 weeks after completion of treatment. A total of 331 patients who were maintained an H. pylori-eradicated state at 1 year after eradication were divided into two groups according to reinfection. For the evaluation of risk factors of reinfection, gender, age, smoking, alcohol, income, education, gastrointestinal symptoms, clinical diagnosis, histologic atrophic gastritis or intestinal metaplasia, and clarithromycin resistance were analyzed.

RESULTS

The follow-up period was 18-95 months (mean: 37.1 months), and H. pylori reappeared in 36 of 331 patients (10.9%), resulting in the annual reinfection rate of 3.51% per year. Multivariate analysis showed that male gender (HR 2.28; 95% CI, 1.05-5.00, p = .037) and low monthly family income (≤5000$ vs >5000$) (HR 3.54; 95% CI, 1.08-11.67, p = .038) were associated with H. pylori reinfection.

CONCLUSION

This long-term reinfection rate of H. pylori stayed rather low (3.51% per year), and male and low income determined the reinfection, factors already known to be important for H. pylori infection.

Low rate of recurrence of Helicobacter pylori infection in spite of high clarithromycin resistance in Pakistan

BACKGROUND

The aim was to investigate the reinfection rate of H. pylori during a follow-up period of 12 months in adults who had undergone eradication therapy.

METHODS

One hundred-twenty patients; 116 with gastritis, 3 with duodenal ulcer and 1 gastric ulcer, were studied. Their mean age was 41±13 years (range 18-77) and male: female ratio of 2:1. H. pylori were cultured and antibiotic sensitivity was determined by Epsilometer test (E-test) for clarithromycin (CLR) and amoxicillin (AMX). Primers of urease C gene of H. pylori and Sau-3 and Hha I restriction enzymes were used for polymerase chain reaction-restriction fragment length polymorphism analysis (PCR-RFLP). 14C urea breath test (14C-UBT) was performed 4 weeks after the eradication therapy. The successfully treated patients were observed for 12 months with 14C-UBT to assess H. pylori status. If 14C-UBT was negative, it was repeated after every 12 weeks. If 14C-UBT was positive, endoscopy was repeated with biopsies.

RESULT

The eradication therapy was successful in 102(85%) patients. Out of forty-seven H. pylori isolates cultured, clarithromycin sensitivity was present in 30(64%) and amoxicillin in 45(98%), respectively. Follow-up 14C-urea breath tests of all 102 patients who eradicated H. pylori remained negative up to 9 months. However, in 6 patients, the 14C-UBT confirmed recurrence at 12 months. The recurrence rate was 6%.

CONCLUSION

A low rate of recurrence of H. pylori infection was found in patients with dyspeptic symptoms. H. pylori isolates demonstrated a high invitro clarithromycin resistance.

Helicobacter pylori persistence in children: distinguishing inadequate treatment, resistant organisms, and reinfection

Helicobacter pylori is a worldwide infection that causes chronic gastritis, duodenal ulcers, and malignancy. Transmission of Helicobacter pylori within a family appears to be the predominant mode of contamination. Recurrence of the infection is frequently seen following treatment. Lack of eradication due to either inadequate treatment or resistant bacteria vs. reinfection have been explanations for detection of H. pylori following treatment. In this article we will discuss the concepts of inadequate treatment vs. resistant infection and reinfection as causes of persistent H. pylori infection.

Accuracy of diagnostic tests for Helicobacter pylori in patients with peptic ulcer bleeding

BACKGROUND AND AIMS

To assess the validity of biopsy-based tests (histology, culture, and urease test) and serology in detecting current H. pylori infection for the peptic ulcer patients who had gastric bleeding.

METHODS

A total of 398 peptic ulcer patients were enrolled and divided into two groups, according to the presence or absence of bleeding. The diagnosis for current H. pylori infection was verified using the gold standard combining individual H. pylori tests. Sensitivity, specificity, and positive and negative predictive values of the culture, Campylobacter-like organism (CLO) test (urease test), histology, and serology were compared.

RESULTS

Of the total study population (N = 398), 157 (39.4%) patients were categorized into the bleeding group. The sensitivities of the culture (40.0%) and CLO (85.0%) in the bleeding group were significantly lower than culture (58.1%) and CLO (96.4%) in the nonbleeding group (p = .012 and p < .001, respectively). In the bleeding group, the sensitivity of CLO (85.0%) was significantly lower than histology (92.5%) and serology (97.4%) (p = .013 and p = .002, respectively), which was not found in the nonbleeding group. The specificity of serology in the bleeding group (56.3%) was significantly lower than that of nonbleeding group (74.2%) (p = .038). Similarly, the specificity of serology was significantly lower than the other H. pylori tests in the bleeders.

CONCLUSIONS

Bleeding decreased the sensitivity of H. pylori tests in patients with peptic ulcer, especially in urease test or culture. In contrast, histology was found to be a quite reliable test, regardless of the presence of bleeding.

Reinfection rate and endoscopic changes after successful eradication of Helicobacter pylori

AIM: To determine the long-term outcomes regarding reinfection with Helicobacter pylori (H. pylori) and endoscopic changes after successful H. pylori eradication.

METHODS: From June 1994 to January 2007, 186 patients (M:F = 98:88; mean age 50.0 ± 11.4 years), in whom H. pylori had been successfully eradicated, were enrolled. The mean duration of follow up was 41.2 ± 24.0 mo.

RESULTS: H. pylori reinfection occurred in 58 patients (31.2%). The average annual reinfection rate was 9.1% per patient year. No recurrence of peptic ulcer was detected at the follow up endoscopy. There were no significant differences between the H. pylori eradication regimens for the reinfection rate and no significant differences in endoscopic findings between the H. pylori-recurred group and the H. pylori-cured group.

CONCLUSION: The reinfection rate in Korea is 9.1% which represents a decreasing trend. There was no relationship between H. pylori infection status and changes in endoscopic findings. There was also no recurrence or aggravation of ulcers.

Dietary and socio-economic factors in relation to Helicobacter pylori re-infection

AIM: To examine if dietary and socio-economic factors contribute to Helicobacter pylori (H pylori) re-infection.

METHODS: The population of patients consisted of subjects in whom H pylori infection had been successfully treated in the past. Patients were divided into two groups: I-examined group (111 persons with H pylori re-infection) and II-control group (175 persons who had not been re-infected). The respondents were interviewed retrospectively on their dietary habits and socio-economic factors.

RESULTS: A statistically significant lower frequency of fermented dairy products (P < 0.0001), vegetables (P = 0.02), and fruit (P = 0.008) consumption was noted among patients with H pylori re-infection as compared to those who had not been re-infected.

CONCLUSION: High dietary intake of probiotic bacteria, mainly Lactobacillus, and antioxidants, mainly vitamin C (contained in fruit and vegetables), might decrease the risk of H pylori re-infection.

Review article: 'true' re-infection of Helicobacter pylori after successful eradication--worldwide annual rates, risk factors and clinical implications

BACKGROUND

The incidence of 'true' re-infection with Helicobacter pylori after successful eradication remains uncertain.

AIM

To determine the worldwide rates, risk factors and clinical implications of 'true' re-infection of Helicobacter pylori. 'True' re-infection of H. pylori is defined as the situation where tests for H. pylori infection, which were negative for 12 months after eradication, become positive again at a later stage.

RESULTS

Thirty six studies were identified through a literature search to be able to produce annual rates of 'true' re-infection, and data from 33 original articles were considered reliable and adequate in the further review. Generally, the reported rates varied from 0% to 23.4% in adults and from 1.9% to 9.6% in children. Most studies from developed countries reported rates of less than 1%, whereas relatively higher rates were reported in most of the developing countries. Small sample sizes included in the studies appeared to be associated with increased re-infection rates. Interfamilial transmission is the major cause of re-infection, although iatrogenic re-infection through contaminated endoscopic equipment has been reported.

CONCLUSION

Helicobacter pylori re-infection is not a concern in a clinical setting, especially in the developed world; however, caution must be exercised in most developing countries.

Lafutidine versus lansoprazole in combination with clarithromycin and amoxicillin for one versus two weeks for Helicobacter pylori eradication in Korea

BACKGROUND AND AIMS

Lafutidine is a novel H(2)-receptor antagonist with gastroprotective activity that includes enhancement of gastric mucosal blood flow. The aim of the present study was to test the efficacy of 7- or 14-day lafutidine-clarithromycin-amoxicillin therapy versus a lansoprazole-based regimen for Helicobacter pylori eradication.

METHODS

Four hundred and sixty-three patients with H. pylori-infected peptic ulcer disease were randomized to one of four regimens: (1) lafutidine (20 mg b.i.d.), clarithromycin (500 mg b.i.d.) and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LFT group) or (2) for 14 days (the 14LFT group); (3) lansoprazole (30 mg b.i.d.), clarithromycin (500 mg b.i.d.), and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LPZ group); or (4) for 14 days (the 14LPZ group). The eradication rates, drug compliance, and adverse effects among the four regimens were compared.

RESULTS

The eradication rates by the intention-to-treat and per-protocol analyses in the 7LFT and 7LPZ groups were 76.5% and 81.6%, and 76.9% and 82.0% (p = .94 and .95), respectively. The eradication rates by intention-to-treat and per-protocol analyses in the 14LFT and 14LPZ groups were 78.2% and 82.2%, and 80.4% and 85.9% (p = .70 and .49), respectively. The treatment duration for 7 days or 14 days did not affect the eradication rates. In addition, the adverse effect rates and discontinuation rates were similar among the four groups. Furthermore, the ulcer cure rate and symptom response rate were similar in the lafutidine and lansoprazole groups.

CONCLUSION

The results of this study showed that lafutidine-clarithromycin-amoxicillin therapy was a safe and effective as lansoprazole-based triple therapy for the eradication rate of H. pylori, and could be considered as an additional treatment option.

Long-term follow up of Helicobacter pylori IgG serology after eradication and reinfection rate of H. pylori in South Korea

BACKGROUND

Serology is widely used for epidemiologic research of Helicobacter pylori. However, there is limited information on the long-term follow up of H. pylori titers after eradication. In addition, it is presumed that the reinfection rate decreases as the H. pylori infection rate decreases. The aim of this study was to investigate the long-term follow up of H. pylori IgG, and to evaluate the reinfection rate of H. pylori in Korea.

METHODS

Among 247 patients, who were enrolled during 2003-07, 185 patients with invasive H. pylori test positive received proton pump inhibitor-based triple therapy, and follow-up H. pylori testing, including histology, CLOtest, culture, and serology, were evaluated 2, 10, and 18 months after H. pylori eradication.

RESULTS

The initial H. pylori IgG optical density (OD(450 nm)), 2.06, gradually decreased to 0.63 (67% reduction) at 18 months after H. pylori eradication. The seroreversion rate was 5, 10, and 45% at 2, 10, and 18 months after H. pylori eradication, respectively. The recrudescence of H. pylori was 3.49%, and the annual reinfection rate was 2.94% per year. H. pylori IgG titers abruptly increased in cases with recrudescence and reinfection, and correlated with the results of the invasive H. pylori tests.

CONCLUSION

The results of this study showed that H. pylori IgG serology could be used for the determination of reinfection of H. pylori, but not for the diagnosis of H. pylori eradication. The reinfection rate of H. pylori, in Korea, was found to be very low, 2.94% per year.

Helicobacter pylori infection and development of gastric cancer in Korea: long-term follow-up

BACKGROUND AND AIM

Infection of Helicobacter pylori is viewed as a major driver of progression to the precancerous state or to gastric cancer. This study was performed to investigate the effect of H. pylori infection on gastric cancer development and to determine to what extent H. pylori eradication is likely to reduce the prevalence of gastric cancer.

METHODS

Gastric cancer development was investigated in 1790 Korean subjects who underwent gastroscopy and H. pylori testing between 1992 and 1998. The effects of H. pylori-positive and eradicated states on gastric cancer development were analyzed.

RESULTS

Gastric cancer developed in 5 of the study cohort during a mean follow-up period of 9.4 years. All of these patients were positive for H. pylori infection, and 4 of the 5 had antral intestinal metaplasia (IM) at the time of study enrollment. One of these 5 patients was in an eradicated state when the gastric cancer was diagnosed, and had histologic IM before eradication therapy was performed. Gastric cancer was found to develop 10.9 times more frequently in the presence of IM than in its absence.

CONCLUSIONS

The present study shows a close relationship between H. pylori infection and IM, and between IM and the development of gastric cancer. In addition, our finding suggests that chronic H. pylori infection looks like an important risk factor for the development of gastric cancer in Korea, where the prevalence of H. pylori remains high. This study indicates that to prevent gastric cancer H. pylori eradication is best performed before the development of IM.

Progression of atrophic gastritis and intestinal metaplasia drives Helicobacter pylori out of the gastric mucosa

This study was performed to evaluate the implication of anti-H. pylori IgG positivity when CLOtest, histological test, and culture in the antrum and body are all negative, and to find out the specific disease category that is more affected by the hostile relationship of atrophic gastritis and intestinal metaplasia (IM) with H. pylori. Four hundred thirty-six patients (84 controls, 69 with duodenal ulcer, 96 with benign gastric ulcer, 43 with dysplasia, 144 with gastric cancer), who had not received any eradication therapy, were divided into three groups according to H. pylori test: CLOtest or histological H. pylori-positive group (group A; 294 cases), only anti-H. pylori IgG-positive group (group B; 62 cases), and anti-H. pylori IgG-negative group (group C; 80 cases). The grade of neutrophil and monocyte infiltration, atrophic gastritis, and IM was compared according to the updated Sydney system classification. Neutrophil and monocyte infiltrations were significantly severe in the group A. In contrast, the grade of atrophic gastritis and IM in the antrum was significantly higher in group B than the other two groups, A or C. When patients were divided according to the disease outcome in each group, the grade of IM in the body was statistically higher only in the patients with cancer or dysplasia in group B. These results suggest that anti-H. pylori IgG positivity with all negative invasive H. pylori tests represents past infection with H. pylori rather than a false negative, especially in the case of dysplasia and gastric cancer.

Helicobacter pylori recurrence in patients with duodenal ulcer: Clinical, endoscopic, histologic, and genotypic aspects. A 10-year Brazilian series

BACKGROUND

Recurrence infection following successful eradication of Helicobacter pylori is usually low, except for countries with high prevalence of H. pylori. The aim of this study was to verify H. pylori recurrence rate in patients with duodenal ulcer after eradication and the possible relationship with environmental factors, histologic pattern of the mucosa and bacterial genotype.

MATERIALS AND METHODS

One-hundred and ninety-four patients with an active duodenal ulcer and who were successfully treated for H. pylori infection from 1990 to 1999 were studied. A questionnaire was answered about their living conditions, and a 14C-urea breath test was performed. Patients with a positive breath test underwent an upper endoscopy to investigate for possible ulcer recurrence; gastric biopsy samples were than collected for rapid urease test and for histologic assessment. H. pylori vacA and cagA genotype was determined by polymerase chain reaction in those samples with positive urease test.

RESULTS

H. pylori infection was detected in 11 patients (recurrence rate of 5.7%) that were not associated with the type of bacterial virulence. In 10 patients the ulcer was healed and all of them were clinically asymptomatic. In eight, histology showed an intensification of gastritis. All 11 patients had adequate housing and sanitary conditions and no other risk for H. pylori recurrence was identified.

CONCLUSIONS

The recurrence rate of H. pylori in Brazil was higher than that reported in developed countries, but lower than usually reported in developing ones. Ulcer relapse rarely occurs even in long-term follow up.

Long-term outcomes after Helicobacter pylori eradication with second-line, bismuth-containing quadruple therapy in Korea

OBJECTIVES

To determine the long-term outcomes in terms of Helicobacter pylori and ulcer recurrence after second-line eradication with bismuth-containing quadruple regimens in Korea.

METHODS

Sixty-seven patients with peptic ulcer disease after successful eradication using second-line quadruple therapies were prospectively followed up 1 month after treatment and then every 6 months or when dyspeptic symptoms reappeared to ascertain H. pylori and ulcer status.

RESULTS

Three patients were lost during follow-up. The median duration of follow-up of the remaining 64 patients was 26.8 months. H. pylori recurrence occurred in 11 of these 64 patients (17.2%), giving a calculated reinfection rate of 6.0% per patient-year. Only one of the 11 patients was reinfected by 12 months after treatment completion. Four of 11 patients (36.4%) who became reinfected experienced peptic ulcer recurrence, but none of 53 patients who were not reinfected experienced recurrence. No evidence was obtained to indicate that the reinfection rate depended on the age, sex, ulcer location, or eradication regimens. The relapse of dyspeptic symptoms was the only factor predictive of H. pylori recurrence.

CONCLUSION

This study suggests that the recurrence rate of H. pylori at 1 year after second-line, bismuth-containing quadruple therapy is low, but the annual reinfection rate is as high as 6%. Surveillance for H. pylori reinfection facilitating peptic ulcer recurrence may be warranted even after a second eradication, especially when dyspeptic symptoms reappear in Korea.

Follow-up care after a diagnosis of Helicobacter pylori infection in an Asian immigrant cohort

GOAL

To study the rate at which Helicobacter pylori infection is treated in an immigrant cohort after diagnosis by esophagogastroduodenoscopy (EGD).

BACKGROUND

Gastric cancer is the second leading cause of cancer death worldwide, and is especially prevalent in East Asia; immigrants from this part of the world remain at higher risk. Infection with H. pylori is a known risk factor for gastric cancer. There have been no studies of completion of H. pylori treatment in immigrant populations.

STUDY

Prospective cohort study of East Asian immigrants diagnosed with H. pylori infection who underwent EGD in a gastric cancer screening protocol. Our primary outcome was self-report or chart evidence of completion of treatment of H. pylori.

RESULTS

Sixty-eight of the 126 participants (54%) tested positive for H. pylori infection on EGD. Forty-nine (72%) were seen for a follow-up visit at one of the clinics involved in the study. According to clinic records, 39 of these 49 participants (57% of all H. pylori-positive participants) were prescribed treatment. Only 31 participants (46%) completed treatment. Of possible explanatory factors, only having a "regular doctor" was significantly associated with treatment completion (odds ratio=5.6; 95% confidence interval, 1.2-25.0).

CONCLUSIONS

In a sample of Asian immigrants, the rate of treatment of H. pylori infection, a potentially modifiable risk factor, was lower than expected. Having a "regular doctor" appeared to increase the likelihood of receiving appropriate follow-up care.

Long-term follow-up after eradication of Helicobacter pylori with omeprazole, clarithromycin, and tinidazole (OCT regimen) in a Japanese population

BACKGROUND

The long-term benefit of Helicobacter pylori eradication treatment that includes metronidazole on peptic ulcer disease in Japan is unclear. We investigated the rate of H. pylori re-infection and ulcer relapse after H. pylori eradication.

MATERIALS AND METHODS

A total of 266 patients with endoscopically confirmed peptic ulcer disease and H. pylori infection were treated with triple therapy of omeprazole 40 mg (20 mg b.i.d.), clarithromycin 800 mg (400 mg b.i.d.), and tinidazole 1000 mg (500 mg b.i.d.) for 7 days. Endoscopy with gastric biopsy was performed before and 1 month, 6 months, 1.5 years, and 3.5 years after therapy. H. pylori status was determined by H. pylori culture, rapid urease test, and histopathology. 13C-urea breath test was done at 6 months after eradication therapy. Treatment was deemed successful when all tests were negative at 6 months after therapy by endoscopic biopsy.

RESULTS

Successful H. pylori eradication was achieved in 262/266 (98.5%) patients with peptic ulcer. Total relapse of peptic ulcer occurred in 8/262 (3%) patients after eradication, with 3/262 (1.1%) occurring within 1.5 years after treatment and 5/262 (1.9%) within 3.5 years. All relapsed patients were found to be H. pylori-positive at the time of relapse. Of the 262 patients who experienced eradication, 20 (7.6%) were subsequently re-infected, six (2.3%) within 1.5 years and 14 (5.3%) within 3.5 years.

CONCLUSION

Triple therapy with omeprazole, clarithromycin, and tinidazole (OCT) is useful for H. pylori eradication in Japan, but there is an appreciable re-infection rate in this population.

The recurrence of Helicobacter pylori infection: incidence and variables influencing it. A critical review

The rate of H. pylori recurrence after eradication of the microorganism seems to be relatively low, at least in developed countries, where the mean annual reinfection rate is of approximately 3% per patient-year of follow-up, although the risk of reinfection in some developing regions is considerably higher. Several findings suggest that recrudescence rather than reinfection is likely to be responsible for most cases of recurrence: (i) the recurrences decrease with time and decline sharply after the first year, and (ii) studies using molecular fingerprinting techniques (polymerase chain reaction [PCR]) confirm that the identified microorganisms (before and after therapy) are usually genetically identical. The lower the efficacy of an antibiotic therapy, the greater the likelihood that recurrence occur, again suggesting that in these cases temporary "clearance" has been achieved rather than true eradication. The value of the (13)C-urea breath test after treatment is higher in those patients who suffer a recurrence; therefore, selection of a lower cut-off value may be helpful to maintain the diagnostic accuracy of posttreatment breath test, and thus preventing recrudescences. The observation of a pattern of histological (active) gastritis without the concomitant finding of H. pylori must raise the suspicion of a diagnostic error. Some studies suggest that recurrence is relatively infrequent, even if the patient's spouse is H. pylori-positive, suggesting that the patient's partner does not act as a reservoir for the reinfection. However, other investigators achieve contrary results, although a common exogenous source of H. pylori (for both partner's infection and patient's reinfection) cannot be ruled out. The oral cavity may be a potential source for recrudescence of gastric infection after successful therapy. When peptic ulcer reappears (sometimes with bleeding recurrence) or gastric MALT (mucosa-associated lymphoid tissue) lymphoma relapses after previous H. pylori eradication, recolonization of the gastric mucosa by the organism has almost always occurred.

High rates of recurrence and of transient reinfections of Helicobacter pylori in a population with high prevalence of infection

OBJECTIVES

Little is known concerning the magnitude of reinfection versus recrudescence of Helicobacter pylori (H. pylori) infection after eradication treatment. The aims of this study were to determine the magnitude of H. pylori reinfection versus recrudescence, and to identify possible risk factors for reinfection.

METHODS

Children and adults with upper GI symptoms treated at the Centro Médico Nacional Siglo XXI (Instituto Mexicano del Seguro Social, in Mexico City, Mexico) were studied. H. pylori infection was diagnosed with urea breath test (UBT), histology, and culture. Infected patients received triple therapy, and those who became UBT negative 4-6 wk after treatment were considered as eradicated and were included in the study. A cohort of 141 patients in whom the disease was eradicated was monitored for recurrence with UBT at 3, 6, 9, 12, 18, and 24 months. H. pylori was isolated from gastric biopsy samples before treatment and at recurrence and isolates compared by genotyping.

RESULTS

During this period, 32 (22.7%) cases of recurrence were documented the majority occurring during yr 1. In nine of the 32 (28.1%) cases, recurrence was eradicated spontaneously, suggesting these were transient reinfections. Recurrence rates were significantly higher in the subjects 41-60 yr of age than in younger or older subjects. H. pylori isolates from 12 recurrence cases were genotyped; nine (75%) were classified as true reinfection and three as recrudescence.

CONCLUSIONS

In our population, recurrence rate is high in adults and transient reinfection is common. In several cases, reinfection occurred by multiple strains, which suggests that soon after eradication, patients are exposed to multiple sources of reinfection.

Is the recurrence of Helicobacter pylori infection after eradication therapy resultant from recrudescence or reinfection, in Japan

BACKGROUND

Reinfection of Helicobacter pylori after eradication is rare in developed countries but most often occurs within 1 year. In the present study, we attempted to differentiate between reinfection and recrudescence of H. pylori strains between 6 months and 6 years after successful eradication in Japan, a country with a high prevalence of H. pylori infection.

MATERIALS AND METHODS

After successful eradication of H. pylori, 274 patients were followed up by endoscopy and urea breath test. In recurrent patients, H. pylori strains isolated initially and after recurrence were compared using PCR-based restriction fragment length polymorphism (RFLP) analysis.

RESULTS

Recurrence of H. pylori occurred in 15 of 274 patients (5.5%) at 6 months after eradication and the annual recurrence rate was 2.0% per patient year (between 1 and 6 years). PCR-based RFLP analysis of H. pylori strains isolated initially and after recurrence showed that 62.5% (at 6 months) and 100% (after 1 years) of bacteria were of different strains.

CONCLUSION

Reinfection of H. pylori was not as rare at 6 months after eradication as reported previously, and up to 6 years after eradication, the annual reinfection rate is 2.0% per patient year in Japan.

Effect of Helicobacter pylori eradication on duodenal ulcer scar in patients with no clinical history of duodenal ulcer

BACKGROUND

Helicobacter pylori eradication has become the standard treatment for duodenal ulcer. However, there is no relevant evidence for antibacterial treatment of the white scar stage of duodenal ulcer (duodenal ulcer scar) in patients with no past history of duodenal ulcer.

AIM

To investigate whether H. pylori eradication could decrease duodenal ulcer recurrence in patients with duodenal ulcer scar and no past history of duodenal ulcer.

PATIENTS AND METHODS

We prospectively enrolled 66 patients with duodenal ulcer scar: 53 were H. pylori-positive and 13 were H. pylori-negative. H. pylori-positive patients were randomly assigned into two groups (two-to-one allocation): 36 patients were assigned to the treatment group and 17 to the follow-up group. Thirteen H. pylori-negative patients were followed up according to the study protocol. Follow-up endoscopy was performed to evaluate ulcer scar changes and H. pylori status 6 weeks after anti-H. pylori treatment and then every 6 months for up to 30 months.

RESULTS

Active duodenal ulcer recurrence was identified in seven of 23 H. pylori-positive/non-cured patients (30%). There was no duodenal ulcer recurrence in 43 H. pylori-negative/cured patients (0%), which was significantly different in terms of duodenal ulcer recurrence (P=0.001).

CONCLUSIONS

H. pylori eradication is effective at preventing active duodenal ulcer recurrence in patients with duodenal ulcer scar and no past history of duodenal ulcer.

Recurrence of Helicobacter pylori infection and the long-term outcome of peptic ulcer after successful eradication in Japan

Recurrence of peptic ulcer after successful eradication of Helicobacter pylori is closely associated with reinfection. The aim of this study was to examine the recurrence of peptic ulcer and reinfection with H. pylori after successful eradication. To eradicate H. pylori infection, patients with active peptic ulcer disease were assigned to two treatment groups depending on the year of their enrollment (AM group and OAMR group). Patients in the AM group received 400 mg of cimetidine twice per day, 300 mg of amoxicillin three times per day, and 250 mg of metronidazole three times per day for 2 weeks. Patients in the OAMR group received 20 mg of omeprazole once per day, 500 mg of amoxicillin granules three times per day, 250 mg of metronidazole three times per day, and 150 mg of roxithromycin twice per day for 1 week. After endoscopy verified ulcer scarring and successful eradication of H. pylori infection, study patients were followed up monthly and did not undergo acid-suppressive therapy. Endoscopy was performed at 6-month intervals for the 1st year. After the 1st year, follow-up endoscopies were performed annually. In total, 107 patients with peptic ulcer (duodenal ulcer [DU], 65; gastric ulcer [GU], 42) were followed up for a mean period of approximately 2 years. Recurrence of infection occurred in 10 (9.3%) of 107 patients (AM group, 9; OAMR group, 1) after 210 patient-years of follow-up; the recurrence rate was 4.8% per patient-year. Recurrence of H. pylori infection was significantly higher in the AM group (23.1%) than in the OAMR group (1.5%). H. pylori infection recurred in two patients 6 months after eradication therapy, in seven 1 year after, and in one 2 years after. Thereafter, no further cases of H. pylori recurrence were observed. During follow-up periods, seven cases of ulcer recurrence were observed (DU, 4; GU, 3). The rate of peptic ulcer recurrence within 2 years after eradication therapy was significantly higher than that after more than 2 years. Four cases of ulcer recurrence (DU, 3; GU, 1) also had recurrence of H. pylori infection. One recurrent case of DU without reinfection was associated with nonsteroidal anti-inflammatory drugs. The remaining two cases of GU recurred without H. pylori reinfection. In conclusion, peptic ulcer recurrence rarely occurred (3 [2.9%] of 103) in patients cured of H. pylori infection. Reinfection after apparent successful eradication was rarely noted when a powerful therapeutic regimen in eradication was used. Therefore, to eradicate H. pylori, a highly effective therapeutic regimen should always be used.

Recrudescence and reinfection with Helicobacter pylori after eradication therapy in Bangladeshi adults

BACKGROUND & AIMS

In developing countries where Helicobacter pylori infection is widespread, posttherapeutic recurrence rates may be high. Many of the limited studies available have methodological problems and show varied recurrence rates. We determined late recrudescence rates, true reinfection, and ulcer recurrence.

METHODS

One hundred five Bangladeshi patients with H. pylori infection and duodenal ulcer disease were treated with a triple therapy. Follow-up included 13C-urea breath tests, endoscopy, and biopsy-based tests. In reinfected patients, genomic typing compared pretherapeutic and posttherapeutic strains.

RESULTS

Recrudescence, associated with nitroimidazole-based treatment, occurred in 15 of 105 patients (14%) within the first 3 months, but only 8 of 105 patients tested positive 4 weeks after therapy ended. True reinfection was diagnosed in 11 of 105 patients between 3 and 18 months after therapy. The annual reinfection rate was 13%, based on a total follow-up of 84.7 patient years. Ulcer relapse occurred in 2 of 15 (13%) recrudescence cases and in 6 of 11 (55%) reinfection cases, but also in 4 of 73 (5%) H. pylori-negative patients.

CONCLUSIONS

In Bangladesh, late recrudescence of H. pylori after eradication therapy occurs within the first 3 months. The reinfection rate is high and might influence cost-benefit analyses for determining diagnostic and therapeutic procedures.

Helicobacter pylori in dental plaque and saliva

BACKGROUND

About half of the world population is infected with H. pylori, but the transmission and the source of this infection are still unclear. Recently, dental plaque (DP) and saliva have been implicated as possible sources of H. pylori infection. This study was done to investigate the detection rates of H. pylori in the DP and saliva by use of PCR depending on H. pylori infection state of gastric mucosa.

METHODS

In 46 subjects, gastric H. pylori colonization was evaluated with CLO test, microscopy of Gram stained mucosal smear, culture and histology after modified Giemsa staining in the antrum and body, respectively. A patient was regarded as H. pylori positive if one or more of the four aforementioned test methods demonstrated H. pylori colonization of the gastric mucosa. For detection of H. pylori in the DP and saliva, PCR assay was done with ET4-U and ET4-L primers. To estimate the sensitivity and specificity of this PCR, H. pylori positivity was evaluated in the antrum and body, separately.

RESULTS

The sensitivity of mucosal PCR was 50.0% (27/54) and the specificity 86.8% (33/38). When a subject was regarded as H. pyloi positive, if either antrum or body mucosal H. pylori was is positive, the positive rate of mucosal PCR was 62.1% (18 subjects) in the 29 H. pylori-positive and 17.6% (3 subjects) in the 17 H. pylori-negative subjects. DP PCR was positive in 2 of 29 H. pylori-positive subjects (6.9%) and none in the 17 H. pylori-negative (0%). Saliva PCR was positive in 4 of 14 H. pylori-positive subjects (28.6%) and none of 6 H. pylori-negative (0%).

CONCLUSION

The detection rates of H. pylori in DP and saliva by PCR were rather low, 6.9% and 28.6%, respectively, and these rates might have been underestimated by low sensitivity of the PCR method used in this study. However, the results that H. pylori was found in the DP and saliva suggest that the oral cavity can perform a role as a reservoir of H. pylori in Korea.