Effect of Helicobacter pylori eradication on the ulcer recurrence rate after simple closure of perforated duodenal ulcer: retrospective and prospective randomized controlled studies

Analysis of risk factors for duodenal leak after repair of a duodenal perforation

BACKGROUND

Repairing of a duodenal perforation is a well accepted procedure, but clinically, approximately 4% of patients develop duodenal leaks after perforation repair, increasing the risk of death. We retrospectively analyzed clinical data from 168 patients at our hospital to explore risk factors for duodenal leak after perforation repair and developed a nomogram for predicting postoperative duodenal leak.

METHODS

This retrospective case-control study totalled 168 patients undergoing repair of a duodenal perforation with omentopexy at the General Surgery Department, Dongnan Hospital of Xiamen University, from January 2012 to January 2022. The patients were divided into the non-leak group and the leak group. Risk factors were evaluated by analyzing the patient's sex, shock, diameter and anatomic position of the ulcer, use of NSAIDS and Glucocorticoid, history of drinking, diabetes, chronic diseases, age, time of onset of symptoms and lab tests.

RESULT

One hundred fifty-six patients (92.9%) who did not develop leaks after repair of a duodenal perforation were included in the non-leak group, and 12 (7.1%) developed leaks were included in the leak group. In univariate analysis, there were significant differences between the two groups referring to age, shock, NSAIDs, albumin, and perforation size (P < 0.05). The area under the ROC curve for perforation diameter was 0.737, the p-value was 0.006, the optimal cutoff point was 11.5, sensitivity was 58.3%, and specificity was 93.6%, the positive predictive value is 41.1%, and the negative predictive value is 98.0%. In the internal validation of the performance of the nomogram, the C-index and AUC of the model were 0.896(95%CI 0.81-0.98), demonstrating that the nomogram model was well calibrated.

CONCLUSION

The study discussed the risk factors for postoperative duodenal leak in patients undergoing repair of a duodenal perforation, and a nomogram was constructed to predict the leak. Future prospective studies with large sample sizes and multiple centres are needed to further elucidate the risk of duodenal leak after repair of a duodenal perforation.

Surgical Clinical Trials in India: Underutilized Opportunities

Clinical trials in Surgery are central to research; however, very few surgical clinical trials are conducted in India. Such paucity of surgical trials is a cause for concern, and prompted us to explore the recent landscape of surgical trials in India. We reviewed all clinical trials from general surgery or subspecialties of general surgery registered with the Clinical Trials Registry of India website between 2018 to 15 th May 2021. Specific details such as the surgical subspecialty, study design, multicentric or single institution and funding were obtained. We found a total of 16,710 trials, out of these 4119 (24.6%) were related to all surgical fields. Only 136 (0.8%) trials were found from general surgery and its subspecialties. Most trials were registered from Central Government Institutions (48%), followed by State Government Medical Colleges (11%). Most number of trials was registered from GI surgery (32%). Most (90.5%) trials were single centre based. Common barriers to research are well known; if the State Government Medical Colleges can mentor a culture of research from an early stage of surgical training it can improve research productivity. Multicentre trials, involving smaller hospitals from tier 2 and tier 3 cities, are a potential solution to one of the major obstacles of surgical trials i.e. small number of patients; especially in this pandemic induced draught of elective surgical operations. A positive change in attitude of surgeons and provision of necessary funding can encourage more surgical clinical trials in India.

Evidence-based clinical practice guidelines for peptic ulcer disease 2020

The Japanese Society of Gastroenterology (JSGE) revised the third edition of evidence-based clinical practice guidelines for peptic ulcer disease in 2020 and created an English version. The revised guidelines consist of nine items: epidemiology, hemorrhagic gastric and duodenal ulcers, Helicobacter pylori (H. pylori) eradication therapy, non-eradication therapy, drug-induced ulcers, non-H. pylori, and nonsteroidal anti-inflammatory drug (NSAID) ulcers, remnant gastric ulcers, surgical treatment, and conservative therapy for perforation and stenosis. Therapeutic algorithms for the treatment of peptic ulcers differ based on ulcer complications. In patients with NSAID-induced ulcers, NSAIDs are discontinued and anti-ulcer therapy is administered. If NSAIDs cannot be discontinued, the ulcer is treated with proton pump inhibitors (PPIs). Vonoprazan (VPZ) with antibiotics is recommended as the first-line treatment for H. pylori eradication, and PPIs or VPZ with antibiotics is recommended as a second-line therapy. Patients who do not use NSAIDs and are H. pylori negative are considered to have idiopathic peptic ulcers. Algorithms for the prevention of NSAID- and low-dose aspirin (LDA)-related ulcers are presented in this guideline. These algorithms differ based on the concomitant use of LDA or NSAIDs and ulcer history or hemorrhagic ulcer history. In patients with a history of ulcers receiving NSAID therapy, PPIs with or without celecoxib are recommended and the administration of VPZ is suggested for the prevention of ulcer recurrence. In patients with a history of ulcers receiving LDA therapy, PPIs or VPZ are recommended and the administration of a histamine 2-receptor antagonist is suggested for the prevention of ulcer recurrence.

Perforated peptic ulcer - an update

Peptic ulcer disease (PUD) affects 4 million people worldwide annually. The incidence of PUD has been estimated at around 1.5% to 3%. Perforated peptic ulcer (PPU) is a serious complication of PUD and patients with PPU often present with acute abdomen that carries high risk for morbidity and mortality. The lifetime prevalence of perforation in patients with PUD is about 5%. PPU carries a mortality ranging from 1.3% to 20%. Thirty-day mortality rate reaching 20% and 90-d mortality rate of up to 30% have been reported. In this review we have summarized the current evidence on PPU to update readers. This literature review includes the most updated information such as common causes, clinical features, diagnostic methods, non-operative and operative management, post-operative complications and different scoring systems of PPU. With the advancement of medical technology, PUD can now be treated with medications instead of elective surgery. The classic triad of sudden onset of abdominal pain, tachycardia and abdominal rigidity is the hallmark of PPU. Erect chest radiograph may miss 15% of cases with air under the diaphragm in patients with bowel perforation. Early diagnosis, prompt resuscitation and urgent surgical intervention are essential to improve outcomes. Exploratory laparotomy and omental patch repair remains the gold standard. Laparoscopic surgery should be considered when expertise is available. Gastrectomy is recommended in patients with large or malignant ulcer.

Sequential versus concomitant therapy for eradication of Helicobacter Pylori in patients with perforated duodenal ulcer: A randomized trial

OBJECTIVES

Comparison of Helicobacter pylori eradication rates, side effects, compliance, cost, and ulcer recurrence of sequential therapy (ST) with that of concomitant therapy (CT) in patients with perforated duodenal ulcer following simple omental patch closure.

METHODS

Sixty-eight patients with perforated duodenal ulcer treated with simple closure and found to be H. pylori positive on three months follow-up were randomized to receive either ST or CT for H. pylori eradication. Urease test and Giemsa stain were used to assess for H. pylori eradication status. Follow-up endoscopies were done after 3 months, 6 months, and 1 year to evaluate the ulcer recurrence.

RESULTS

H. pylori eradication rates were similar in ST and CT groups on intention-to-treat (ITT) analysis (71.43% vs 81.80%,P = 0.40). Similar eradication rates were also found in per-protocol (PP) analysis (86.20% vs 90%,P = 0.71). Ulcer recurrence rate in ST groups and CT groups at 3 months (17.14% vs 6.06%,P = 0.26), 6 months (22.86% vs 9.09%,P = 0.19), and at 1 year (25.71% vs 15.15%,P = 0.37) of follow-up was also similar by ITT analysis. Compliance and side effects to therapies were comparable between the groups. The most common side effects were diarrhoea and metallic taste in ST and CT groups, respectively. A complete course of ST costs Indian Rupees (INR) 570.00, whereas CT costs INR 1080.00.

CONCLUSION

H. pylori eradication rates, side effects, compliance, cost, and ulcer recurrences were similar between the two groups. The ST was more economical compared with CT.

Treatment for perforated gastric ulcer: a multi-institutional retrospective review

BACKGROUND

The optimal treatment for patients with perforated gastric ulcer (PGU) remains controversial. This study therefore investigated the treatment status for this disease in clinical practice.

METHODS

We retrospectively reviewed 183 patients with PGU from 1998 to 2007 across 15 institutions, and analyzed patient characteristics and short- and long-term outcomes according to treatments received.

RESULTS

Of the 183 patients, 57 who were treated conservatively had less abdominal tenderness, lower levels of serum C-reactive protein, and shorter time to presentation than the 126 patients who underwent emergency surgery. There was no significant difference in baseline characteristics between the 41 successful patients and 16 failed patients in the conservative treatment group; however, the latter had a longer average hospital stay. Eighty-three of the emergency surgery patients who underwent gastrectomy had longer surgical times, greater blood loss, and shorter time to resumption of diet than the 57 patients undergoing stomach-preserving surgery; however, there was no significant difference in postoperative complications and hospital stay between these groups. Of 91 patients who received stomach-preserving treatment, only three had treatment failure in the long-term follow-up period.

CONCLUSION

Strictly selected patients should be initially considered for conservative treatment. The short-term outcomes of stomach-preserving surgery are comparable to gastrectomy; however, further evaluation of the long-term outcomes of stomach-preserving treatment is required.

Standard triple versus levofloxacin based regimen for eradication of Helicobacter pylori

AIM

To compare the eradication rates for Helicobacter pylori (H. pylori) and ulcer recurrence of standard triple therapy (STT) and levofloxacin based therapy (LBT).

METHODS

Seventy-four patients with perforated duodenal ulcer treated with simple closure and found to be H. pylori infected on 3 mo follow up were randomized to receive either the STT group comprising of amoxicillin 1 g bid, clarithromycin 500 mg bid and omeprazole 20 mg bid or the LBT group comprising of amoxicillin 1 g bid, levofloxacin 500 mg bid and omeprazole 20 mg bid for 10 d each. The H. pylori eradication rates, side effects, compliance and the recurrence of ulcer were assessed in the two groups at 3 mo follow up.

RESULTS

Thirty-four patients in the STT group and 32 patients in the levofloxacin group presented at 3 mo follow up. H. pylori eradication rates were similar with STT and the LBT groups on intention-to-treat (ITT) analysis (69% vs 80%, P = 0.425) and (79% vs 87%, P = 0.513) by per-protocol (PP) analysis respectively. Ulcer recurrence in the STT and LBT groups on ITT analysis was (20% vs 14%, P = 0.551) and (9% vs 6%, P = 1.00) by PP analysis. Compliance and side effects were also comparable between the groups. A complete course of STT costs Indian Rupees (INR) 1060.00, while LBT costs only INR 360.00.

CONCLUSION

H. pylori eradication rates and the rate of ulcer recurrence were similar between the STT and LBT. The LBT is a more economical option compared to STT.

Standard triple versus levofloxacin based regimen for eradication of Helicobacter pylori

AIM

To compare the eradication rates for Helicobacter pylori (H. pylori) and ulcer recurrence of standard triple therapy (STT) and levofloxacin based therapy (LBT).

METHODS

Seventy-four patients with perforated duodenal ulcer treated with simple closure and found to be H. pylori infected on 3 mo follow up were randomized to receive either the STT group comprising of amoxicillin 1 g bid, clarithromycin 500 mg bid and omeprazole 20 mg bid or the LBT group comprising of amoxicillin 1 g bid, levofloxacin 500 mg bid and omeprazole 20 mg bid for 10 d each. The H. pylori eradication rates, side effects, compliance and the recurrence of ulcer were assessed in the two groups at 3 mo follow up.

RESULTS

Thirty-four patients in the STT group and 32 patients in the levofloxacin group presented at 3 mo follow up. H. pylori eradication rates were similar with STT and the LBT groups on intention-to-treat (ITT) analysis (69% vs 80%, P = 0.425) and (79% vs 87%, P = 0.513) by per-protocol (PP) analysis respectively. Ulcer recurrence in the STT and LBT groups on ITT analysis was (20% vs 14%, P = 0.551) and (9% vs 6%, P = 1.00) by PP analysis. Compliance and side effects were also comparable between the groups. A complete course of STT costs Indian Rupees (INR) 1060.00, while LBT costs only INR 360.00.

CONCLUSION

H. pylori eradication rates and the rate of ulcer recurrence were similar between the STT and LBT. The LBT is a more economical option compared to STT.

Standard triple versus levofloxacin based regimen for eradication of Helicobacter pylori

AIM: To compare the eradication rates for Helicobacter pylori (H. pylori) and ulcer recurrence of standard triple therapy (STT) and levofloxacin based therapy (LBT).

METHODS: Seventy-four patients with perforated duodenal ulcer treated with simple closure and found to be H. pylori infected on 3 mo follow up were randomized to receive either the STT group comprising of amoxicillin 1 g bid, clarithromycin 500 mg bid and omeprazole 20 mg bid or the LBT group comprising of amoxicillin 1 g bid, levofloxacin 500 mg bid and omeprazole 20 mg bid for 10 d each. The H. pylori eradication rates, side effects, compliance and the recurrence of ulcer were assessed in the two groups at 3 mo follow up.

RESULTS: Thirty-four patients in the STT group and 32 patients in the levofloxacin group presented at 3 mo follow up. H. pylori eradication rates were similar with STT and the LBT groups on intention-to-treat (ITT) analysis (69% vs 80%, P = 0.425) and (79% vs 87%, P = 0.513) by per-protocol (PP) analysis respectively. Ulcer recurrence in the STT and LBT groups on ITT analysis was (20% vs 14%, P = 0.551) and (9% vs 6%, P = 1.00) by PP analysis. Compliance and side effects were also comparable between the groups. A complete course of STT costs Indian Rupees (INR) 1060.00, while LBT costs only INR 360.00.

CONCLUSION: H. pylori eradication rates and the rate of ulcer recurrence were similar between the STT and LBT. The LBT is a more economical option compared to STT.

Is Helicobacter pylori Infection the Primary Cause of Duodenal Ulceration or a Secondary Factor? A Review of the Evidence

Helicobacter pylori (H. pylori) has a role in the multifactorial etiology of peptic ulcer disease. A link between H. pylori infection and duodenal ulcer disease is now established. Other contributing factors and their interaction with the organism may initiate the ulcerative process. The fact that eradication of H. pylori infection leads to a long-term cure in the majority of duodenal ulcer patients and the fact that the prevalence of infection is higher in ulcer patients than in the normal population are cogent arguments in favor of it being the primary cause of the ulceration. Against this concept there are issues that need explanation such as the reason why only a minority of infected persons develop duodenal ulceration when infection with H. pylori is widespread. There is evidence that H. pylori infection has been prevalent for several centuries, yet duodenal ulceration became common at the beginning of the twentieth century. The prevalence of duodenal ulceration is not higher in countries with a high prevalence of H. pylori infection. This paper debate puts forth the point of view of two groups of workers in this field whether H. pylori infection is the primary cause of duodenal ulcer disease or a secondary factor.

Eradication of Helicobacter pylori for prevention of ulcer recurrence after simple closure of perforated peptic ulcer: a meta-analysis of randomized controlled trials

BACKGROUND

Eradication of Helicobacter pylori has become part of the standard therapy for peptic ulcer. However, the role of H pylori eradication in perforation of peptic ulcers remains controversial. It is unclear whether eradication of the bacterium confers prolonged ulcer remission after simple repair of perforated peptic ulcer.

METHODS

A systematic review and meta-analysis of randomized controlled trials was performed to evaluate the effects of H pylori eradication on prevention of ulcer recurrence after simple closure of perforated peptic ulcers. The primary outcome to evaluate these effects was the incidence of postoperative ulcers; the secondary outcome was the rate of H pylori elimination.

RESULTS

The meta-analysis included five randomized controlled trials and 401 patients. A high prevalence of H pylori infection occurred in patients with perforated peptic ulcers. Eradication of H pylori significantly reduced the incidence of ulcer recurrence at 8 wk (risk ratio 2.97; 95% confidence interval: 1.06-8.29) and 1 y (risk ratio 1.49; 95% confidence interval: 1.10-2.03) postoperation. The rate of H pylori eradication was significantly higher in the treatment group than in the nontreatment group.

CONCLUSIONS

Eradication therapy should be provided to patients with H pylori infection after simple closure of perforated gastroduodenal ulcers.

Construction and use of a prokaryotic expression system for Helicobacter pylori AhpC

Background

Helicobacter pylori is an important pathogen responsible for human gastric problems like inflammation, ulcers and cancer. It is widely prevalent in developing countries with low socioeconomic status. Since the infection remains asymptomatic in most individuals, efforts for efficient diagnostic markers to identify high risk patients are warranted. In this study, we constructed an expression vector that overexpresses the H. pylori AhpC protein as a glutathione S-transferase fusion protein. We furthermore examined whether this recombinant fusion protein retained immunogenicity and thus would be useful as a diagnostic marker.

Findings

The full-length tsaA gene from H. pylori strain G27, which encodes AhpC, was cloned in plasmid vector pGEX-6P-2 to create the recombinant plasmid vector pGEX-tsaA. The nucleotide sequence of the clone showed 100% homology with corresponding published sequence of original gene. Over-expression of the target protein GST-AhpC was achieved in E. coli BL21 (DE3) cells by induction with isopropyl-beta-D-thiogalactoside (IPTG). GST-AhpC was extracted and identified using SDS-PAGE as a 52 kDa protein. Western blotting results using commercial antibodies against whole cell H. pylori showed that the fusion protein retained immunogenecity.

Conclusion

A recombinant prokaryotic expression system was successfully established with high expression efficiency for target fusion gene pGEX-tsaA. The expressed GST-AhpC protein showed immunoreactivity against commercial anti-H. pylori antibodies. This recombinant fusion protein can be developed as a diagnostic marker for screening patients with chronic H. pylori infections.

Systematic review and meta-analysis: Helicobacter pylori eradication therapy after simple closure of perforated duodenal ulcer

BACKGROUND

The most common complications of peptic ulcer are bleeding and perforation. In many regions, definitive acid reduction surgery has given way to simple closure and Helicobacter pylori eradication.

AIM

To perform a systematic review and meta-analysis to ask whether this change in practice is in fact justified.

MATERIALS AND METHODS

A search on the Cochrane Controlled Trials Register, Medline, and Embase was made for controlled trials of duodenal ulcer perforation patients using simple closure method plus postoperative H. pylori eradication therapy versus simple closure plus antisecretory non-eradication therapy. The long-term results for prevention of ulcer recurrence were compared.

RESULTS

The pooled incidence of 1-year ulcer recurrence in H. pylori eradication group was 5.2% [95% confidence interval (CI) of 0.7 and 9.7], which is significantly lower than that of the control group (35.2%) with 95% CI of 0.25 and 0.45. The pooled relative risk was 0.15 with 95% CI of 0.06 and 0.37.

CONCLUSIONS

Helicobacter pylori eradication after simple closure of duodenal ulcer perforation gives better result than the operation plus antisecretory non-eradication therapy for prevention of ulcer recurrence. All duodenal ulcer perforation patients should be tested for H. pylori infection, and eradication therapy is required in all infected patients.

Sequential therapy versus standard triple drug therapy for eradication of Helicobacter pylori in patients with perforated duodenal ulcer following simple closure

BACKGROUND

Resistance to clarithromycin, a component of standard triple therapy, leads to inconsistent eradication rates of Helicobacter pylori infection. Some studies have shown higher eradication rates for H. pylori using sequential regimen. This study was done to compare the eradication rates for H. pylori infection between the standard triple drug therapy and the sequential therapy.

METHODS

Seventy-three patients with perforated duodenal ulcer following simple closure with H. pylori infection were randomized to receive either standard triple drug therapy or the sequential therapy. Standard triple drug therapy comprised of omeprazole, clarithromycin, and amoxicillin for 10 days. Sequential therapy comprised of omeprazole and amoxicillin or the first 5 days followed by omeprazole, clarithromycin, and amoxicillin for the next 5 days. Follow-up endoscopy was done at 2 months to assess the eradication rates, compliance, and side effects with each regimen.

RESULTS

Eradication rates for standard triple therapy and sequential regimen were 81.25% and 87.09%, respectively (p = 0.732). The cost of sequential therapy was cheaper and incidence of side effects and compliance were similar in each group.

CONCLUSION

Standard triple therapy and sequential therapy have similar efficacy for eradication of H. pylori and sequential therapy is an economical alternative to standard triple therapy.

Respiratory distress and chest pain: a perforated peptic ulcer with an unusual presentation

Background

Dyspnea and chest pain are common presenting complaints to the ED, and coupled together can present a challenging diagnostic dilemma in patients in extremis. A thoughtful evaluation is required, giving due diligence to the immediate life threats as well as multiple etiologies which can cause serious morbidity. A perforated peptic ulcer is one such possibility and requires rapid diagnosis and prompt intervention to avoid the associated high risk of morbidity and mortality.

Method

We present a case report of a 54 year old man with respiratory distress and chest pain as the initial Emergency Department presentation of a perforated duodenal ulcer.

Results

We discuss an unusual presentation of a perforated duodenal ulcer that was recognized in the emergency department and treated promptly. The patient was surgically treated immediately, had a prolonged and complicated post-operative course, but is ultimately doing well. We also provide a brief literature review of the risk factors, imaging choices, and management decision required to treat a perforated ulcer.

Conclusions

Perforated ulcers can have highly varied presentations and are occasionally difficult to diagnose in a complicated patient. Knowledge of the risk factors and a thorough history and physical can point to the diagnosis, but timely and appropriate imaging is often required because delays in diagnosis and treatment lead to poor outcomes. Early administration of antibiotics and immediate surgical repair are necessary to limit morbidity and mortality.

Perforated peptic ulcer: different ethnic, climatic and fasting risk factors for morbidity in Al-ain medical district, United Arab Emirates

AIM

To evaluate risk factors, morbidity and mortality rates of perforated peptic ulcer (PPU) and to investigate factors affecting postoperative complications of PPU.

BACKGROUND

The incidence of PPU has remained constant, simple closure with omental patch repair being the mainstay of treatment.

PATIENTS AND METHODS

One hundred and nineteen patients admitted to Al-Ain Hospital with PPU between January 2000 and March 2004 was studied retrospectively; two with deficient data were excluded from the analysis. Logistic regression was used to define factors affecting postoperative complications.

RESULTS

The mean age of patients was 35.3 years (range, 20-65). 45.7% of patients were Bangladeshi, and 85.3% originated from the Indian subcontinent. One patient, subsequently found to have a perforated gastric cancer, died. In 116 patients, 26 complications were recorded in 20 patients (17.2%). Common risk factors for perforation were smoking, history of peptic ulcer disease (PUD) and use of non-steroidal anti-inflammatory drugs (NSAIDs). A significantly increased risk of perforation was evident during the daytime fasting month of Ramadan. An increase in the acute physiology and chronic health evaluation (APACHE) II score (p = 0.047) and a reduced white blood cell count (0.04) were highly significant for the prediction of postoperative complications.

CONCLUSION

Patients with dyspeptic symptoms and a history of previous PUD should be considered for prophylactic treatment to prevent ulcer recurrence during prolonged daytime fasting in Ramadan, especially during the winter time.

Perforated peptic ulcer: clinical presentation, surgical outcomes, and the accuracy of the Boey scoring system in predicting postoperative morbidity and mortality

BACKGROUND

The purposes of this study were to determine clinical presentations and surgical outcomes of perforated peptic ulcer (PPU), and to evaluate the accuracy of the Boey scoring system in predicting mortality and morbidity.

METHODS

We carried out a retrospective study of patients undergoing emergency surgery for PPU between 2001 and 2006 in a university hospital. Clinical presentations and surgical outcomes were analyzed. Adjusted odds ratio (OR) of each Boey score on morbidity and mortality rate was compared with zero risk score. Receiver-operating characteristic curve analysis was used to compare the predictive ability between Boey score, American Society of Anesthesiologists (ASA) classification, and Mannheim Peritonitis Index (MPI).

RESULTS

The study included 152 patients with average age of 52 years (range: 15-88 years), and 78% were male. The most common site of PPU was the prepyloric region (74%). Primary closure and omental graft was the most common procedure performed. Overall mortality rate was 9% and the complication rate was 30%. The mortality rate increased progressively with increasing numbers of the Boey score: 1%, 8% (OR=2.4), 33% (OR=3.5), and 38% (OR=7.7) for 0, 1, 2, and 3 scores, respectively (p<0.001). The morbidity rates for 0, 1, 2, and 3 Boey scores were 11%, 47% (OR=2.9), 75% (OR=4.3), and 77% (OR=4.9), respectively (p<0.001). Boey score and ASA classification appeared to be better than MPI for predicting the poor surgical outcomes.

CONCLUSIONS

Perforated peptic ulcer is associated with high rates of mortality and morbidity. The Boey risk score serves as a simple and precise predictor for postoperative mortality and morbidity.

Decreasing incidence of peptic ulcer complications after the introduction of the proton pump inhibitors, a study of the Swedish population from 1974-2002

Background

Despite a decreasing incidence of peptic ulcer disease, most previous studies report a stabile incidence of ulcer complications. We wanted to investigate the incidence of peptic ulcer complications in Sweden before and after the introduction of the proton pump inhibitors (PPI) in 1988 and compare these data to the sales of non-steroid anti-inflammatory drugs (NSAID) and acetylsalicylic acid (ASA).

Methods

All cases of gastric and duodenal ulcer complications diagnosed in Sweden from 1974 to 2002 were identified using the National hospital discharge register. Information on sales of ASA/NSAID was obtained from the National prescription survey.

Results

When comparing the time-periods before and after 1988 we found a significantly lower incidence of peptic ulcer complications during the later period for both sexes (p < 0.001). Incidence rates varied from 1.5 to 7.8/100000 inhabitants/year regarding perforated peptic ulcers and from 5.2 to 40.2 regarding peptic ulcer bleeding. The number of sold daily dosages of prescribed NSAID/ASA tripled from 1975 to 2002. The number of prescribed sales to women was higher than to males. Sales of low-dose ASA also increased. The total volume of NSAID and ASA, i.e. over the counter sale and sold on prescription, increased by 28% during the same period.

Conclusion

When comparing the periods before and after the introduction of the proton pump inhibitors we found a significant decrease in the incidence of peptic ulcer complications in the Swedish population after 1988 when PPI were introduced on the market. The cause of this decrease is most likely multifactorial, including smoking habits, NSAID consumption, prevalence of Helicobacter pylori and the introduction of PPI. Sales of prescribed NSAID/ASA increased, especially in middle-aged and elderly women. This fact seems to have had little effect on the incidence of peptic ulcer complications.

Effect of Helicobacter pylori eradication on ulcer recurrence after simple closure of perforated duodenal ulcer

BACKGROUND

This study was conducted to elucidate the prevalence of Helicobacter pylori in patients with a perforated duodenal ulcer and to determine whether eradication of H. pylori prevent ulcer recurrence following simple repair of the perforation.

PATIENTS AND METHOD

Eighty-three patients with perforated duodenal ulcer (68 males); mean age was 47.8 years+/-7.2. Antral mucosal biopsies (to determine the status of HP by rapid urease test, culture and histological examination/staining) were obtained during laparotomy by passing a biopsy forceps through the perforation site. H. pylori positive patients who had undergone patch repair were randomized into the eradication group who received amoxicillin, metranidazole plus omperazole and the control group was given omeprazole alone. Follow-up endoscopy and antral biopsies were performed at 8 weeks, 16 weeks and 1 year to show ulcer healing and determine H. pylori state.

RESULTS

Of 77 patients in the study, 65 patients (84.8%) had H. pylori. These patients were randomly divided into the triple therapy group (34 patients) and the control group (31 patients). Eradication of H. pylori was significantly higher in the triple therapy group than the control group and initial ulcer healing was significantly better in the eradication group. After 1 year, ulcer recurrence was (6.1%) in the eradication group vs. (29.6%) in the control group (P=0.001).

CONCLUSION

H. pylori was present in a high proportion of patients with duodenal ulcer perforation. Eradication of H. pylori after simple closure of a perforated duodenal ulcer reduced the incidence of recurrent ulcer.

Helicobacter genotyping and detection in peroperative lavage fluid in patients with perforated peptic ulcer

INTRODUCTION AND OBJECTIVES

Certain Helicobacter pylori genotypes are associated with peptic ulcer disease; however, little is known about associations between the H. pylori genotype and perforated peptic ulcer (PPU). The primary aim of this study was to evaluate which genotypes are present in patients with PPU and which genotype is dominant in this population. The secondary aim was to study the possibility of determining the H. pylori status in a way other than by biopsy.

MATERIALS AND METHODS

Serum samples, gastric tissue biopsies, lavage fluid, and fluid from the nasogastric tube were collected from patients operated upon for PPU. By means of PCR, DEIA, and LIPA the presence of the "cytotoxin associated gene" (cagA) and the genotype of the "vacuolating cytotoxin gene" were determined.

RESULTS

Fluid from the nasogastric tube was obtained from 25 patients, lavage fluid from 26 patients, serum samples from 20 patients and biopsies from 18 patients. Several genotypes were found, of which the vacA s1 cagA positive strains were predominant. Additionally, a correlation was found between the H. pylori presence in biopsy and its presence in lavage fluid (p=0.015), rendering the latter as an alternative for biopsy. Sensitivity and specificity of lavage fluid analysis were 100% and 67%, respectively.

CONCLUSION

This study shows the vacA s1 cagA positive strain is predominant in a PPU population. The correlation found between the H. pylori presence in biopsy and its presence in lavage fluid suggests that analysis of the lavage fluid is sufficient to determine the H. pylori presence. Risks associated with biopsy taking may be avoided.

Persistence of Helicobacter pylori infection in patients with peptic ulcer perforation

OBJECTIVE

In patients with perforated peptic ulcer (PPU) the convergence between the high eradication rate of Helicobacter pylori infection and low rates of ulcer relapse after treatment has been associated with reinfection by non-virulent strains. The objective of this study was to evaluate the persistence of infection by virulent H. pylori strains and ulcer recurrence in 33 patients with PPU one year after surgery and antimicrobial treatment.

MATERIAL AND METHODS

The histological evaluation and molecular detection of H. pylori cagA and ureA genes, vacA allelic types and the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analyses of the glmM gene products from antral mucosa specimens were performed initially, 2-5 months and 1 year after therapy.

RESULTS

The density of H. pylori colonization was temporarily decreased (p<0.05) 2-5 months after therapy. After one year, complete eradication was achieved in only 7 patients (23%) at histological examination and recurrent ulcers were found in 3/33 (9%) patients. The vacA s1a allelic type of cagA-positive strains persisted in 19/33 (58%) PPU patients with identical PCR-RFLP fingerprints in 8/9 (89%) of the patients.

CONCLUSIONS

In PPU patients with a low eradication rate of H. pylori infection after surgical and antimicrobial treatment, the frequent recrudescence of the infection is mostly caused by the persisting virulent strains of the cagA and vacA s1a subtypes. In the 1-year follow-up period the recurrent ulceration can be postponed just by the lowered colonization density of H. pylori after eradicative therapy.

Helicobacter pylori eradication prevents recurrence after simple closure of perforated duodenal ulcer

BACKGROUND AND AIM

Evidence remains inconclusive as to whether eradication of Helicobacter pylori prevents ulcer relapse after simple closure of a perforated duodenal ulcer. This study was conducted to determine the effect of H. pylori eradication using a quadruple drug regimen along with a probiotic on ulcer recurrence after perforation closure.

METHODS

A total of 93 patients who had presented with perforated duodenal ulcer and had a simple closure of a duodenal perforation comprised the study group. Three months postoperatively, patients who were found to be positive for H. pylori infection (n = 60) were administered quadruple therapy consisting of omeprazole, clarithromycin, amoxicillin and colloidal bismuth subcitrate for 10 days along with the probiotic Lactobacillus sporogenes for 14 days. Diagnosis of H. pylori was carried out by urease test and histology. Patients were followed for 18 months. Recurrence of ulcer was analyzed for correlation with H. pylori status.

RESULTS

Of 60 patients who received H. pylori eradication therapy, 53 were available for subsequent follow up. H. pylori eradication was achieved in 43/53 (81.1%) patients. The ulcer recurrence in the eradicated group was 18.6% (8/43) compared to 70% (7/10) in the noneradicated group (P = 0.003).

CONCLUSION

Eradication of H. pylori significantly reduces the relapse of duodenal ulcer after simple closure of perforation. Anti H. pylori therapy must be recommended for all H. pylori positive patients after simple closure of a perforated duodenal ulcer.

Surgical management of perforated peptic ulcer disease

BACKGROUND

Surgery for perforated peptic ulcer disease is one of the most common emergency procedures carried out in the western world. The role of postoperative empiric Helicobacter Pylori eradication therapy is controversial.

METHODS

The clinical, operative and postoperative surveillance details of 84 consecutive patients who underwent surgery for perforated peptic ulcer were reviewed.

RESULTS

All patients underwent omentopexy +/- simple closure followed by proton pump therapy. Patients were followed-up for an average of 44 +/- 19 months. Females were older than male patients (59 +/- 20 vs. 46 + 17 years; p<0.05), presented with symptoms of a longer duration (17.9 +/- 16 vs. 8.9 +/- 9 hours; p=0.045) and had a higher mortality rate (18% vs 3%; p<0.05). Seventy-nine per cent of patients received postoperative empiric Helicobacter Pylori eradication therapy.

CONCLUSIONS

Surgery for perforated peptic ulcer is associated with a significant perioperative mortality rate. Elderly female patients are particularly at risk.

Multimedia article: management of duodenal ulcer perforation with combined laparoscopic and endoscopic methods

In the past, primary closes for perforated duodenal ulcer were not effective because of the high incidence of recurrence (42%), therefore most surgeons preferred definitive procedures to control acid production. Since the association of Helicobacter pylori with peptic ulcers and the effectiveness of the medication for acid control, definitive surgery is less frequently used. Today, primary closes of the perforation are the immediate alternative. Furthermore laparoscopic repair allows to perform the same technique than open surgery but with the benefits of the minimum invasion. The video shows the management of a 51-year-old woman who came to the emergency room with acute abdomen, leukocytosis, and fever. Laparoscopy showed peritonitis with apparent gastric perforation. Duodenal perforation was confirmed by endoscopy. Primary closes of the perforation, cavity cleaning, and placement of drainages were performed by laparoscopy. Evolution was excellent; the patient left the hospital 3 days after surgery. The contribution of laparoscopic and endoscopic surgery were shown to be highly beneficial for the patient, since an endoscopic view of the stomach and the duodenum was the pertinent approach to assure the correct perforation closes as well as to obtain diagnostic biopsy.

Perforated peptic ulcer treated by simple closure and Helicobacter pylori eradication

Simple closure followed by Helicobacter pylori (Hp) eradication has become the most used procedure in perforated ulcer treatment. However, its efficacy and safety are still to be determined. To assess recurrence and re-perforation rates, and as a secondary objective, to analyze Hp infection rates in perforated ulcer patients and controls, we conducted a prospective study. Ninety-two consecutive patients (ages: 19-96 years) were operated on between 1996 and 2002, and treated by simple closure followed by Hp eradication and NSAID avoidance. The data were prospectively collected in a database. Hp infection was diagnosed in 68 patients (73.9%). Thirty-four patients (37%) consumed nonsteroidal anti-inflammatory drugs (NSAIDs), and 23 (25%) had both Hp infection and NSAID antecedents. The perforation was gastric in 4 cases and pre-pyloric, pyloric or duodenal in 88. There were postoperative complications in 24 patients (26%) and 4 patients died (4.3%). Hp eradication was shown in 46 patients. There was clinical ulcer recurrence in 4 (4.3%); in 3 of them recurrence manifested as re-perforation, all in gastric locations. Overall relapse and re-perforation 1-year crude rates were 6.1% and 4.1%, respectively. Crude rates for non-gastric ulcer recurrence were 0 at 1 year and 2.6% at 2 years and for non-gastric ulcer re-perforation rates were 0 at 1 and 2 years. This therapeutic strategy is associated with a low rate of recurrence and no re-perforations in case of duodenal, pyloric, or pre-pyloric perforated ulcers, but it is not acceptable for perforated gastric ulcers.

Frequencies of the expression of main protein antigens from Helicobacter pylori isolates and production of specific serum antibodies in infected patients

AIM: To investigate the frequencies of the expression of main protein antigens of Helicobacter pylori (H pylori) isolates, such as UreB, VacA, CagA1, HpaA, NapA, FlaA and FlaB and the production of specific antibodies in sera from H pylori-infected patients, and to understand the correlations among the different clinical types of chronic gastritis and peptic ulcer and the infection and virulence of H pylori.

METHODS: H pylori strains in biopsy specimens from 157 patients with chronic gastritis and peptic ulcer were isolated and serum samples from the patients were also collected. The target recombinant proteins rUreB, rVacA, rCagA1, rHpaA, rNapA, rFlaA and rFlaB expressed by the prokaryotic expression systems constructed in our previous studies were collected through Ni-NTA affinity chromatography. Rabbit antisera against rUreB, rVacA, rCagA1, rHpaA, rNapA, rFlaA and rFlaB were prepared by using routine subcutaneous immunization. By using ultrasonic lysates of the isolates as coated antigens, and the self-prepared rabbit antisera as the first antibodies and commercial HRP-labeling sheep anti-rabbit IgG as the second antibody, expression frequencies of the seven antigens in the isolates were detected by ELISA. Another ELISA was established to detect antibodies against the seven antigens in sera of the patients by using the corresponding recombinant proteins as coated antigens, and the sera as the first antibody and HRP-labeling sheep anti-human IgG as the second antibody respectively. Correlations among the different clinical types of chronic gastritis and peptic ulcer and the infection and virulence of H pylori were statistically analysed.

RESULTS: In the 125 isolates of H pylori, the positive rates of UreB, VacA, CagA1, HpaA, NapA, FlaA and FlaB were 100%, 65.6%, 92.8%, 100%, 93.6%, 100% and 99.2% respectively. In the 125 serum samples from the H pylori-infected patients, the positive rates of antibodies against recombinant UreB, VacA, CagA1, HpaA, NapA, FlaA and FlaB were 100%, 42.4%, 89.6%, 81.6%, 93.6%, 98.4% and 92.8% respectively. H pylori strains were isolated from 79.6% (125/157) of the biopsy specimens, but no close correlations among the H pylori infection frequencies and different types of chronic gastritis and peptic ulcer could be found (P>0.05, χ² = 0.01-0.87). The VacA positive rate (82.40%) in the strains isolated from the specimens of patients with peptic ulcer and the anti-VacA positive rate (54.3%) in the sera from the patients were significantly higher than those (51.5%, 32.3%) from the patients with chronic gastritis (P<0.01, χ² = 13.19; P<0.05, χ² = 6.13). When analysis was performed in the different types of chronic gastritis, the VacA in the strains isolated from the specimems of patients with active gastritis showed a higher expression frequency (90.0%) than those from superficial (47.9%) and atrophic gastritis (30.0%) (P<0.05, χ² = 5.93; P<0.01,χ² = 7.50). While analysis was carried out in the strains isolated from the specimens with superficial (93.8%) and active gastritis (100%), NapA showed a higher expression frequency compared to that from atrophic gastritis (60.0%) (P<0.01, χ² = 8.88; P<0.05, χ² = 5.00).

CONCLUSION: The types of chronic gastritis and peptic ulcer and their severity are not associated with H pylori infection frequency but closely related to the infection frequency of different virulent H pylori strains. The optimal antigens for developing vaccine and diagnostic kit are UreB, FlaA, HpaA, FlaB, NapA and CagA1, but not VacA.

Diagnosis of Helicobacter pylori infection and diseases associated with Helicobacter pylori by Helicobacter pylori outer membrane proteins

AIM: To examine the serological response of patients with upper gastrointestinal diseases and Helicobocter pylori (H pylori) infection to two H pylori outer membrane proteins (OMPs) (M_r18000 and M_r26000) acquired by gene recombinant technique, and to determine the diagnostic significance of serological tests derived from these OMPs.

METHODS: Recombinant vectors encoding the two H pylori OMPs were used to transform and express in BL21 (DE3) E.coli. After purification with Ni²⁺-NTA agarose resin, colloid gold kits were prepared with purified recombinant proteins to detect H pylori infection and H pylori-associated diseases by the immunity-marker technology. We selected 150 patients with H pylori infection and digestive symptoms without previous treatment, including chronic gastritis (n = 60), duodenal ulcer (n = 30), gastric ulcer (n = 30), and gastric cancer (n = 30). As controls, 33 H pylori-negative healthy volunteers were also recruited. Serum samples were collected from all subjects, and the antibodies to specific proteins of H pylori were tested with the colloid gold test kits. The sensitivity, specificity and accuracy of the colloid gold tests were evaluated, by using the combination of standard diagnostic methods (¹³C urea breath test and bacteria culture) and classic enzyme-linked immunosorbent assay (ELISA) as reference.

RESULTS: After purification with Ni²⁺-NTA agarose resin, the purity of recombinant fusion proteins was about 95%. The recombinant fusion proteins were recognized by the specific monoclonal antibodies against the two H pylori OMPs, as demonstrated by the ELISA. Of the 150 serum samples from patients infected with H pylori 141 (94.0%) responded positively to the recombinant protein with M_r26000, while the seropositive rates were 95.0%, 96.7%, 96.7% and 90.0% for patients with H pylori-associated chronic gastritis, duodenal ulcer, gastric ulcer, and gastric cancer respectively. The sensitivity, specificity, and accuracy of the colloid gold kit with M_r26000 protein were 94.0%, 97.0%, and 94.5%, respectively. Compared with the classic ELISA, bacteria culture and ¹³C urea breath test results in detecting H pylori-infection, there was no significant difference (P > 0.05). For the colloid gold kit with M_r18000, the seropositive rates were 52.0%, 40.0%, 40.0%, 53.3% and 86.7%, respectively, in H pylori-infected patients, and those with H pylori-associated chronic gastritis, duodenal ulcer, gastric ulcer, and gastric cancer. There was a significant difference (P < 0.05) in seropositivity between patient with gastric cancer (86.7%) and those with other diseases (43.3%).

CONCLUSION: The two colloid gold kits derived from the recombinant OMPs are useful tools either for detecting H pylori infection, or for, predicting H pylori-associated gastric malignancy.

Construction of prokaryotic expression system of ltB-ureB fusion gene and identification of the recombinant protein immunity and adjuvanticity

AIM: To construct ltB-ureB fusion gene and its prokaryotic expression system and identify immunity and adjuvanticity of the expressed recombinant protein.

METHODS: The ureB gene from a clinical Helicobacter pylori (H pylori) strain Y06 and the ltB gene from Escherichia coli (E. coli) strain 44851 were linked into ltB-ureB fusion gene by PCR. The fusion gene sequence was analyzed after T-A cloning. A prokaryotic recombinant expression vector pET32a inserted with ltB-ureB fusion gene (pET32a-ltB-ureB) was constructed. Expression of the recombinant LTB-UreB protein (rLTB-UreB) in E. coli BL21DE3 induced by isopropylthio-β-D-galactoside (IPTG) at different concentrations was detected by SDS-PAGE. Western blot assays were used to examine the immunoreaction of rLTB-UreB by a commercial antibody against whole cell of H pylori and a self-prepared rabbit anti-rUreB serum, respectively, and determine the antigenicity of the recombinant protein on inducing specific antibody in rabbits. GM₁-ELISA was used to demonstrate the adjuvanticity of rLTB-UreB. Immunoreaction of rLTB-UreB to the UreB antibody positive sera from 125 gastric patients was determined by using ELISA.

RESULTS: In comparison with the corresponding sequences of original genes, the nucleotide sequence homologies of the cloned ltB-ureB fusion gene were 100%. IPTG with different dosages of 0.1-1.0 mmol/L could efficiently induce pET32a-ltB-ureB-E. coli BL21DE3 to express the rLTB-UreB. The output of the target recombinant protein expressed by pET32a-ureB-E. coli BL21DE3 was approximately 35% of the total bacterial proteins. rLTB-UreB mainly presented in the form of inclusion body. Western blotting results demonstrated that rLTB-UreB could combine with the commercial antibody against whole cell of H pylori and anti-rUreB serum as well as induce rabbit to produce specific antibody. The strong ability of rLTB-UreB binding bovine GM₁ indicated the existence of adjuvanticity of the recombinant protein. All the UreB antibody positive sera from the patients (125/125) were positive for rLTB-UreB.

CONCLUSION: A recombinant prokaryotic expression system with high expression efficiency of the target fusion gene ltB-ureB was successfully established. The expressed rLTB-UreB showed qualified immunogenicity, antigenicity and adjuvanticity. All the results mentioned above laid a firm foundation for further development of H pylori genetically engineered vaccine.

Detection of Helicobacter pylori cagA gene in patients with digestive diseases in Guangxi and its clinical significance

AIM: To study the positive rate of Helicobacter pylori (H. pylori) cagA gene of strains and the virulence of H. pylori infecting patients in Guangxi, China.

METHODS: H. pylori strains were isolated in gastric biopsy specimens from the patients with chronic gastritis and peptic ulcer in Nanning area of Guangxi. The sequence of D008/R008 primers were used to amplify 297 bp fragment of cagA gene and PCR were used to detect the frequency of cagA gene in the 45 H. pylori isolates.

RESULTS: The positive rate of cagA gene in H. pylori strains was 84.4% (38/45). The positive rate of cagA gene in peptic ulcer (PU) patients was 76.0% (19/25), which was lower than that in chronic gastritis (CG) patients (95.0%,19/20), but there was no significant difference (P > 0.05). The positive rate of cagA gene was higher in female patients than that in male patients (100.0% vs 73.1%, P < 0.01). The positive rate of cagA gene in different age groups was no significant difference (P > 0.05).

CONCLUSION: The positive rate of cagA gene in H. pylori strains among patients in Guangxi is high, and the positive rate is lower in PU patients than that in CG patients, and higher in male than female patients. But there is no significant difference in different age groups.

Helicobacter pylori outer membrane proteins in diagnosis of Helicobacter pylori infection

AIM: To examine the serological response of patient with various upper gastrointestinal diseases and Helicobacter pylori (H. pylori ) infection to H. pylori outer membrane proteins (OMP) with M_r18 000 and 26 000 acquired by gene recombinant technique, and to determine its diagnostic significance.

METHODS: The recombinant vectors encoding OMP of H. pylori with M_r18 000 and 26 000 identified by restriction enzyme or PCR were used to transform and express in BL21 (DE3) E. coli respectively. After purification with Ni²⁺-NTA agarose resin, the colloid gold kits were prepared with purified recombinant proteins to detect H. pylori infection and disease associated with H. pylori by immunity-marker technology. We selected 150 patients with H. pylori infection and digestive symptoms without previous treatment, including chronic superficial gastritis (n = 60), duodenal ulcer (n = 30), gastric ulcer (n = 30), and gastric cancer (n = 30) during one year. Simultaneously, 33 cases without digestive symptoms and H. pylori infection were used as controls. All sera were collected and the antibody responded to specific proteins of H. pylori was tested with the colloid gold test kit. Taking as reference a combination of standard diagnostic methods (¹³C urea breath test, cultivate) and the classic enzyme-linked immunosorbent assay (ELISA) serological tests was compared with the results of this technique, and the sensitivity, specificity and accuracy of the colloid gold test were evaluated.

RESULTS: After purification with Ni²⁺-NTA agarose resin, the purities of recombinant fusion proteins were all about 95%. The ELISA results showed that recombinant fusion proteins could be recognized by monoclonal antibody of anti-H. pylori with Mr18 000 and 26 000 respectively. The results detected using colloid gold kits were as follows: all patients sera infected with H. pylori showed response to recombinant protein with M_r 26 000 were 94.0%, while 95.0%, 96.7%, 96.7% and 90.0% of patients with H. pylori-infected chronic superficial gastritis, duodenal ulcer, gastric ulcer, and gastric cancer respectively, showed responses. Compared with the serum-based ELISA results in detecting H. pylori-infection, there was no significant difference with the colloid gold kits (P > 0.05). The sensitivity, specificity, and accuracy of the rapid test kit with Mr 26 000 protein were 94.0%, 97.0%, and 94.5%, respectively; To recombinant protein with M_r18 000, 52.0%, 40.0%, 40.0%, 53.3% and 86.7%, of patients with H. pylori-infected chronic superficial gastritis, duodenal ulcer, gastric ulcer, and gastric cancer respectively, showed responses. There were a significant difference (P < 0.05) in the detecting rates of H. pylori infection between gastric cancer (86.7%) and the other diseases (43.3%). The results showed the colloid gold kits with Mr26 000 proteins of H. pylori could be used as a conventional examination method, with similar sensitivity and specificity as other conventional examination method, and simultaneously a significant association was found between the serologic response to M_r 18 000 OMP antigen and malignant outcome of H. pylori infection.

CONCLUSION: The two colloid gold kits with M_r18 000 and 26 000 proteins of H. pylori, can be a useful tool for detecting H. pylori infection, as well as predicting H. pylori related gastrointestinal diseases, such as gastric malignancy and peptic ulcer.

Helicobacter pylori lipopolysaccharide: Biological activities in vitro and in vivo, pathological correlation to human chronic gastritis and peptic ulcer

AIM: To determine the biological activity of Helicobacter pylori (H pylori) lipopolysaccharide (H-LPS) and understand pathological correlation between H-LPS and human chronic gastritis and peptic ulcer.

METHODS: H-LPS of a clinical H pylori strain and LPS of Escherichia coli strain O55:B5 (E-LPS) were extracted by phenol-water method. Biological activities of H-LPS and E-LPS were detected by limulus lysate assay, pyrogen assay, blood pressure test and PBMC induction test in rabbits, cytotoxicity test in NIH 3T3 fibroblast cells and lethality test in NIH mice. By using self-prepared rabbit anti-H-LPS serum as the first antibody and commercial HRP-labeled sheep anti-rabbit sera as the second antibody, H-LPS in biopsy specimens from 126 patients with chronic gastritis (68 cases) or gastric ulcer (58 cases) were examined by immunohistochemistry.

RESULTS: Fibroblast cytotoxicity and mouse lethality of H-LPS were weaker than those of E-LPS. But the ability of coagulating limulus lysate of the two LPSs was similar (+/0.5 ng/mL). At 0.5 h after H-LPS injection, the blood pressures of the 3 rabbits rapidly declined. At 1.0 h after H-LPS injection, the blood pressures in 2 of the 3 rabbits fell to zero causing death of the 2 animals. For the other one rabbit in the same group, its blood pressure gradually elevated. At 0.5 h after E-LPS injection, the blood pressures of the three rabbits also quickly declined and then maintained at low level for approximately 1.0 h. At 0.5 h after injection with H-LPS or E-LPS, PBMC numbers of the rabbits showed a remarkable increase. The total positivity rate of H-LPS from 126 biopsy specimens was 60.3% (76/126). H-LPS positivity rate in the biopsy specimens from chronic gastritis (50/68, 73.5%) was significantly higher than that from gastric ulcer (26/58, 44.8%) (χ² = 10.77, P < 0.01). H-LPS positivity rates in biopsy specimens from chronic superficial gastritis (38/48, 79.2%) and chronic active gastritis (9/10, 90.0%) were significantly higher than that of the patients with atrophic gastritis (3/10, 30.0%) (χ² = 7.50-9.66, P < 0.01).

CONCLUSION: The biological activities of H-LPS were weaker than those of E-LPS, the activities of H-LPS of lowering rabbit blood pressure and inducing rabbit PBMC were relatively stronger. H-LPS may play a critical role in inducing inflammatory reaction in human gastritis.

Effects of lactose as an inducer on expression of Helicobacter pylori rUreB and rHpaA, and Escherichia coli rLTKA63 and rLTB

AIM: To demonstrate the effect of lactose as an inducer on expression of the recombinant proteins encoded by Helicobacter pylori ureB and hpaA, and Escherichia coli LTB and LTKA63 genes and to determine the optimal expression parameters.

METHODS: By using SDS-PAGE and BIO-RAD gel image analysis system, the outputs of the target recombinant proteins expressed by pET32a-ureB-E.coliBL21, pET32a-hpaA-E.coliBL21, pET32a-LTKA63-E.coliBL21 and pET32a-LTB-E.coliBL21 were measured when using lactose as inducer at different dosages, original bacterial concentrations, various inducing temperatures and times. The results of the target protein expression induced by lactose were compared to those by isopropyl-β-D-thiogalactoside (IPTG). The proteins were expressed in E.coli.

RESULTS: Lactose showed higher efficiency of inducing the expression of rHpaA, rUreB, rLTB and rLTKA63 than IPTG. The expression outputs of the target recombinant proteins induced at 37 °C were remarkably higher than those at 28 °C. Other optimal expression parameters for the original bacterial concentrations, dosages of lactose and inducing time were 0.8, 50 g/L and 4 h for rHpaA; 0.8, 100 g/L and 4 h for rLTKA63; 1.2, 100 g/L and 5 h for both rUreB and rLTB, respectively.

CONCLUSION: Lactose, a sugar with non-toxicity and low cost, is able to induce the recombinant genes to express the target proteins with higher efficiency than IPTG. The results in this study establish a beneficial foundation for industrial production of H pylori genetic engineering vaccine.

Construction of prokaryotic expression system of 2 148-bp fragment from cagA gene and detection of cagA gene, CagA protein in Helicobacter pylori isolates and its antibody in sera of patients

AIM: To construct a prokaryotic expression system of a Helicobacter pylori (H pylori) cagA gene fragment and establish enzyme-linked immunosorbent assays (ELISA) for detecting CagA and its antibody, so as to understand the manner in which the infection of CagA-expressing H pylori (CagA⁺H pylori) isolates cause diseases.

METHODS: H pylori strains in gastric biopsy specimens from 156 patients with positive results in rapid urease test were isolated. PCR was used to detect the frequency of cagA gene in the 109 H pylori isolates and to amplify a 2 148-bp fragment (cagA1) of cagA gene from a clinical strain Y06. A prokaryotic expression system of cagA1 gene was constructed, and the expression of the target recombinant protein (rCagA1) was examined by SDS-PAGE. Western blotting and immunodiffusion assay were employed to determine the immunoreactivity and antigenicity of rCagA1, respectively. Two ELISAs were established to detect CagA expression in 109 H pylori isolates and the presence of CagA antibody in the corresponding patients’ sera, and the correlations between infection with CagA⁺H pylori and gastritis as well as peptic ulcer were analyzed.

RESULTS: Of all the clinical specimens obtained, 80.8% (126/156) were found to have H pylori isolates and 97.2% of the isolates (106/109) were positive for cagA gene. In comparison with the reported data, the cloned cagA1 fragment possessed 94.83% and 93.30% homologies with the nucleotide and putative amino acid sequences, respectively. The output of rCagA1 produced by the constructed recombinant prokaryotic expression system was approximately 30% of the total bacterial protein. rCagA1 was able to bind to the commercial antibody against the whole-cells of H pylori and to induce the immunized rabbits to produce antibody with an immunodiffusion titer of 1:4. A proportion as high as 92.6% of the H pylori isolates (101/109) expressed CagA and 88.1% of the patients’ serum samples (96/109) were CagA antibody-positive. The percentage of CagA⁺H pylori strains (97.9%) isolated from the biopsy specimens of peptic ulcer appeared to be higher than that from gastritis (88.5%), but the difference was not statistically significant (χ² = 3.48, P > 0.05).

CONCLUSION: rCagA1 produced by the prokaryotic expression system constructed in this study possesses good immunoreactivity and antigenicity, and the established ELISAs can be used to detect CagA of H pylori and its antibody. H pylori isolates show high frequencies of cagA gene and CagA expression, but the infections by CagA⁺H pylori strains are not the most decisive factors to cause gastric diseases.

Construction of prokaryotic expression system of ureB gene from a clinical Helicobacter pylori strain and identification of the recombinant protein immunity

AIM: To clone ureB gene from a clinical isolate of Helicobacter pylori and construct a prokaryotic expression system of the gene and identify immunity of the expressed recombinant protein.

METHODS: ureB gene from a clinical H pylori strain Y06 was amplified by the high fidelity polymerase chain reaction technique. The target DNA fragment amplified from ureB gene was sequenced after T-A cloning. Prokaryotic recombinant expression vector pET32a inserted with ureB gene (pET32a-ureB) was constructed. The expression of recombinant UreB protein (rUreB) in E. coli BL21DE3 induced by isopropylthio-β-D-galactoside (IPTG) at different concentrations was examined by SDS-PAGE. Western blot using commercial antibodies against whole cell of H pylori and an immunodiffusion assay using a self-prepared rabbit anti-rUreB antibody were applied to determine immunity of the target recombinant protein. ELISA was used to detect the antibody against rUreB in sera of 125 H pylori infected patients and to examine rUreB expression in 109 H pylori isolates.

RESULTS: In comparison with the reported corresponding sequences, the nucleotide sequence homology of the cloned ureB gene was from 96.88-97.82% while the homology of its putative amino acid sequence was as high as 99.65-99.82%. The rUreB output expressed by pET32a-ureB-BL21DE3 was approximate 30% of the total bacterial proteins. rUreB specifically combined with the commercial antibodies against whole cell of H pylori and strongly induced rabbits to produce antibody with a 1:8 immunodiffusion titer after the animals were immunized with the recombinant protein. Serum samples from all H pylori infected patients were positive for UreB antibody and UreB expression were detectable in all tested H pylori isolates.

CONCLUSION: A prokaryotic expression system with high expression efficiency of H pylori ureB gene was successfully established. The expressed rUreB showed qualified immunoreactivity and antigenicity. High frequencies of UreB expression in different H pylori isolates and specific antibody against UreB in sera of H pylori infected patients indicate that UreB is an excellent antigen candidate for developing H pylori vaccine.

Construction of a prokaryotic expression system of vacA gene and detection of vacA gene, VacA protein in Helicobacter pylori isolates and ant-VacA antibody in patients’ sera

AIM: To construct a recombinant prokaryotic expression vector inserted with Helicobacter pylori vacA gene and identify the immunity of the expressed recombinant protein, and to determine prevalence of vacA-carrying/VacA expressing H pylori isolates and seroprevalence of specific ant-VacA antibody in H pylori infected patients.

METHODS: Polymerase chain reaction technique was used to amplify complete vacA gene of H pylori strain NCTC11637 and to detect vacA gene in 109 H pylori isolates. The amplification product of the complete vacA gene was sequenced after T-A cloning. A recombinant expression vector inserted with a complete vacA gene fragment, named as pET32a-vacA, was constructed. Expression of the target recombinant protein VacA (rVacA) was examined by SDS-PAGE. Western blot using commercial antibodies against whole cell of H pylori and an immunodiffusion assay using self-prepared rabbit anti-rVacA antibody were applied to determine immunoreaction and antigenicity of rVacA. Two ELISA methods were established to detect VacA expression in H pylori isolates and the specific anti-VacA antibody in sera from 125 patients infected with H pylori.

RESULTS: In comparison with the reported corresponding sequences, homologies of nucleotide and putative amino acid sequences of the cloned vacA gene were 99.82% and 100%, respectively. The constructed recombinant prokaryotic expression system efficiently produced rVacA. rVacA was able to combine with the commercial antibodies against whole cell of H pylori and to induce the immunized rabbit to produce specific antibody with an immunodiffusion titer of 1:4. All tested H pylori isolates carried vacA gene, but only 66.1% expressed VacA protein. Of the serum samples tested, 42.4% were positive for specific anti-VacA antibody.

CONCLUSION: A prokaryotic expression system of H pylori vacA gene was successfully constructed. The expressed rVacA can be used to detect specific anti-VacA antibody in human and to prepare antiserum in animals. The high frequency of vacA gene in H pylori isolates, but with a low frequency of VacA expression and specific anti-VacA antibody in H pylori infected patients implies that VacA is not an ideal antigen for H pylori vaccine.

Laparoscopic and endoscopic management of perforated duodenal ulcers

BACKGROUND

Acid peptic perforation of the duodenum remains a surgical challenge. Plication alone may be satisfactory management if the ulcer diathesis is medically controlled. Laparoscopic management for plication has been safely applied in a variety of populations. This study assessed a combination of endoscopy and laparoscopy to manage early duodenal perforation.

STUDY DESIGN

Forty-two patients with early (less than 12 hours) perforation were managed by laparoscopic plication and lavage. Endoscopy identified the site of perforation and guided repair in 35 of 42. All patients were followed with Helicobacter pylori treatment and examined by endoscopy at 3 months. Forty case control patients who had open procedures for duodenal perforation were evaluated for comparison.

RESULTS

Endoscopic/laparoscopic management was completely effective and compared favorably with open procedures with regard to surgical time and complications. Endoscopic snaring of omentum and pulling into the defect proved to be an effective adjunct for plication.

CONCLUSIONS

Endoscopic/laparoscopic repair of perforated duodenal ulcers is a safe and effective surgical tactic if followed by treatment for Helicobacter pylori.

Cloning, expression and antigenic analysis of heat shock protein A gene of human Helicobacter pylori

AIM

To construct a recombinant vector containing gene encoding heat shock protein A with a Mr of 13 000 from human Helicobacter pylori (H pylori) and express it in E. coli BL21, and to explore the antigenicity.

METHODS

The target gene was amplified from H pylori chromosome by PCR, and then inserted into the prokaryotic expression vector pET32a (+) digested by restrictive endonuclease enzymes of kpn I, BamH I simultaneously. The recombinant vector was transformed and expressed in E.coli BL21.The antigenicity of recombinant fusion protein was analysed by Western blot.

RESULTS

Enzyme digestion and sequencing analysis showed that the target gene has been inserted into the recombinant vector, but as compared with the gene reported by GenBank, 1.6% of gene mutation and 1.6% of amino acid residues change in H pylori occurred, respectively. SDS-PAGE analysis showed that the recombinant vector could be expressed in E.coli BL21, the relative molecular mass (Mr) of expressed product was 33×10³, while Mr of protein expressed by pET32a (+) was about 20×10³, and soluble fusion expression product accounted for 18.96% of total bacterial protein. After purification with Ni+-NTA agarose resin, the purity of recombinant fusion protein was about 95%. Western blot result showed that recombinant fusion protein could be recognized by anti-H pylori positive serum, suggesting that the protein had good antigenicity.

CONCLUSION

The gene encoding H pylori heat shock protein A has been cloned and expressed successfully. The results lay the foundation for development of H pylori protein vaccine and a quick diagnostic kit for detection of H pylori infection.

Construction of expression systems for flaA and flaB genes of Helicobacter pylori and determination of immunoreactivity and antigenicity of recombinant proteins

AIM: To clone flagellin genes A (flaA) and B (flaB) from a clinical strain of Helicobacter pylori (H pylori) and to construct prokaryotic expression systems of the genes and identify immunity of the fusion proteins.

METHODS: The flaA and flaB genes from a clinical H pylori isolate Y06 were amplified by high fidelity PCR. The nucleotide sequences of target DNA amplification fragments from the two genes were sequenced after T-A cloning. The recombinant expression vector pET32a inserted with flaA and flaB genes was constructed, respectively. The expressions of FlaA and FlaB fusion proteins in E. coli BL21DE3 induced by isopropylthio-β-D-galactoside (IPTG) at different concentrations were examined by SDS-PAGE. Western blot using commercial antibodies against whole cell of H pylori and immunodiffusion assay using self-prepared rabbit antiserum against FlaA (rFlaA) or FlaB (rFlaB) recombinant proteins were applied to the determination of the fusion proteins immunity. ELISA was used to detect the antibodies against rFlaA and rFlaB in sera of 125 H pylori infected patients and to examine rFlaA and rFlaB expression in 98 clinical isolates of H pylori, respectively.

RESULTS: In comparison with the reported corresponding sequences, the nucleotide sequence homologies of the cloned flaA and flaB genes were from 96.28%-97.13% and 96.31%-97.73%, and their putative amino acid sequence homologies were 99.61%-99.80% and 99.41%-100% for the two genes, respectively. The output of rFlaA and rFlaB expressed by pET32a-flaA-BL21DE3 and pET32a-flaB-BL21DE3 systems was as high as 40%-50% of the total bacterial proteins. Both rFlaA and rFlaB were able to combine with the commercial antibodies against whole cell of H pylori and to induce rabbits to produce specific antibodies with the same 1:2 immunodiffusion titers after the animals were immunized with the two recombinant proteins. Ninety-eight and zero point 4 and 92.80% of the serum samples from 125 patients infected with H pylori were positive for rFlaA and rFlaB antibodies, respectively. One hundred percent and 98.98% of the 98 tested isolates of H pylori were detectable for rFlaA and rFlaB epitopes, respectively.

CONCLUSION: Two prokaryotic expression systems with high efficiency of H pylori flaA and flaB genes were successfully established. The expressed rFlaA and rFlaB showed satisfactory immunoreactivity and antigenicity. High frequencies of FlaA and FlaB expression in different H pylori clinical strains and the general existence of specific antibodies against FlaA and FlaB in H pylori infected patients strongly indicate that FlaA and FlaB are excellent antigen candidates for developing H pylori vaccine.

Construction and characterization of bivalent vaccine candidate expressing HspA and Mr18000 OMP from Helicobacter pylori

AIM: To construct a recombinant vector which can express outer membrane protein (OMP) with M_r18000 and heat shock protein A (HspA) from Helicobacter pylori (H. pylori) in E. coli BL21, and to exploit the possibility for obtaining the vaccine conferring protection from H. pylori infection.

METHODS: The target gene of HspA was amplified from H. pylori chromosome by PCR, and then inserted into the prokaryotic expression vector pET32a (+) by restrictive endonuclease enzyme kpn I, BamH I simultaneously. The recombinant vector was used to sequence, and then together with pET32a (+)/Omp₁₈, digested by restrictive endonuclease enzyme Hind III and BamH I simultaneously. pET32a(+)/ HspA and Omp₁₈ were recovered from 1% agarose gel by gel kit, and ligated with T₄ ligase by BamH I digested viscidity end. The recombinant plasmid of pET32a(+)/HspA/Omp₁₈ was transformed and expressed in E. coli BL21 (DE3) under induction of IPTG. After purification, its antigenicity of the fusion protein was detected by Western blot.

RESULTS: Enzyme digestion analysis and sequencing showed that the target genes were inserted into the recombinant vector, composed of 891 base pairs, encoded objective polypeptides of 297 amino acid residues. Compared with GenBank reported by Tomb et al there were 1.3% and 1.4% differences in obtained H. pylori nucleotide sequence and amino acid residues, respectively. SDS-PAGE analysis showed that relative molecule mass (M_r) of the expressed product was M_r 51000, M_r of protein expressed by pET32a (+) was about M_r 20000, and soluble expression product accounted for 18.96% of total bacterial protein. After purification with Ni⁺²-NTA agarose resins, the purification of recombinant fusion protein was about 95%. Western blot showed that recombinant fusion protein could be recognized by the patients’ serum infected with H. pylori and anti-Omp₁₈ monoclone, suggesting that this protein had good antigenicity.

CONCLUSION: The gene coding for H. pylori M_r18000 OMP and HspA was cloned and expressed successfully. The results obtained lay the foundation for development of H. pylori protein vaccine and a quick diagnostic kit.

How Helicobacter Pylori changed the life of surgeons

Helicobacter Pylori infection has been identified as a pathogenic factor in a number of gastroduodenal diseases, most importantly in gastric and duodenal ulcer disease. This association and the development of H. PYLORI eradication therapies has had a tremendous influence on the surgical therapy for these disorders. Decades ago, surgery was the therapy of choice for gastric and duodenal ulcers. Now, however, the first line of therapy includes treatment of H. PYLORI infection, suppression of gastric acid secretion, and protection of gastric mucosal barriers combined with a range of endoscopic procedures. These developments have had a major impact on the indications for surgery in benign gastroduodenal diseases. In addition, advances in our understanding of the pathogenetic mechanisms of H. PYLORI infection have also changed our views of gastric mucosa-associated lymphoid tissue lymphoma, gastric cancer, and gastroesophageal reflux disease.

Construction of hpaA gene from a clinical isolate of Helicobacter pylori and identification of fusion protein

AIM: To clone hpaA gene from a clinical strain of Helicobacter pylori and to construct the expression vector of the gene and to identify immunity of the fusion protein.

METHODS: The hpaA gene from a clinical isolate Y06 of H. pylori was amplified by high fidelity PCR. The nucleotide sequence of the target DNA amplification fragment was sequenced after T-A cloning. The recombinant expression vector inserted with hpaA gene was constructed. The expression of HpaA fusion protein in E.coli BL21(DE3) induced by IPTG at different dosages was examined by SDS-PAGE. Western blot with commercial antibody against whole cell of H. pylori as well as immunodiffusion assay with self-prepared rabbit antiserum against HpaA fusion protein were applied to determine immunity of the fusion protein. ELISA was used to detect the antibody against HpaA in sera of 125 patients infected with H. pylori and to examine HpaA expression of 109 clinical isolates of H. pylori.

RESULTS: In comparison with the reported corresponding sequences, the homologies of nucleotide and putative amino acid sequences of the cloned hpaA gene were from 94.25%-97.32% and 95.38%-98.46%, respectively. The output of HpaA fusion protein in its expression system of pET32a-hpaA-BL21(DE3) was approximately 40% of the total bacterial proteins. HpaA fusion protein was able to combine with the commercial antibody against whole cell of H. pylori and to induce rabbit producing specific antiserum with 1:4 immunodiffusion titer after the animal was immunized with the fusion protein. 81.6% of the serum samples from 125 patients infected with H. pylori (102/125) were positive for HpaA antibody and all of the tested isolates of H. pylori (109/109) were detectable for HpaA.

CONCLUSION: A prokaryotic expression system with high efficiency of H. pylorihpaA gene was successfully established. The HpaA expressing fusion protein showed satisfactory immunoreactivity and antigenicity. High frequencies of HpaA expression in different H. pylori clinical strains and specific antibody production in H. pylori infected patients indicate that HpaA is an excellent and ideal antigen for developing H. pylori vaccine.

Helicobacter pylori infection and perforated peptic ulcer prevalence of the infection and role of antimicrobial treatment

Although the role of Helicobacter pylori infection on noncomplicated peptic ulcer disease has been definitively established, the precise relationship between the organism and complicated ulcer has hardly been studied. The mean prevalence of H. pylori infection in patients with perforated peptic ulcer is of only about 65-70%, which contrasts with the almost 90-100% figure reported in noncomplicated ulcer disease. However, H. pylori infection rates in various studies range markedly from 0% to 100%, suggesting that differences in variables as number and type of diagnostic methods used to diagnose H. pylori infection, or frequency of nonsteroidal anti-inflammatory drug intake, may be responsible for the low prevalence reported in some studies. Recurrent ulcer disease after peptic ulcer perforation mainly occurs in patients with H. pylori infection, which suggests that the microorganism plays an important role in this complication. All patients with perforated peptic ulcer should be treated by simple closure of the perforation and with therapy aimed at healing of the ulcer and eradicating the H. pylori infection, as disappearance of the organism prevents, or at least decreases, ulcer recurrence and ulcer perforation in patients with H. pylori-associated perforated ulcers after simple closure. Therefore, H. pylori eradicating treatment should be started during the immediate postoperative period. The patients with intractable recurrent symptoms of peptic ulcer despite adequate medical treatment, but without H. pylori infection (e.g. a patient using nonsteroidal anti-inflammatory drugs), is probably the only remaining indication for elective definitive surgical treatment of peptic ulcer disease.

Recombinant Helicobacter pylori catalase

AIM: To construct a recombinant strain which highly expresses catalase of Helicobacter pylori (H. pylori) and assay the activity of H. pylori catalase.

METHODS: The catalase DNA was amplified from H. pylori chromosomal DNA with PCR techniques and inserted into the prokaryotie expression vector pET-22b (+), and then was transformed into the BL21 (DE3) E. coli strain which expressed catalase recombinant protein. The activity of H. pylori catalase was assayed by the Beers&Sizers.

RESULTS: DNA sequence analysis showed that the sequence of catalase DNA was the same as GenBank’s research. The catalase recombinant protein amounted to 24.4% of the total bacterial protein after induced with IPTG for 3 hours at 37 °C and the activity of H. pylori catalase was high in the BL21 (DE3) E. coli strain.

CONCLUSION: A clone expressing high activity H. pylori catalase is obtained, laying a good foundation for further studies.

Construction of clone expressing adhesin Hsp60 of Helicobacter pylori

AIM

To construct a recombinant vector containing gene encoding Hsp60 gene of Helicobacter pylori and to express the vector in E.coli BL21.

METHODS

The Hsp60 gene was amplified from H.pylori chromosome by PCR and inserted into the prokaryotie expression vector pET-22b (+). The recombinant vector was transformed and expressed in E.coli BL21 (DE3). Recombinant Hsp60 protein immunogenicity was studied by Western blot.

RESULTS

The 1.6 kb Hsp60 gene was successfully isolated. Recombinant E.coli strains expressed Hsp60 were obtained, the expression protein amounted to 27.2% of the total bacterial protein after induced with IPTG for 3 h at 37 ℃, which included inclusion body and soluble protein. Inclusion body was the major pattern of the expression that amounted to 76.6% of the insoluble protein. Western blot analysis of rHsp60 confirmed that it could be specially recognized by serum from Hp infected patients.

CONCLUSION

The gene coding for Hp Hsp60 is cloned and expressed successfully. The results obtained lay the foundation for constructing the H.pylori vaccine.