Helicobacter pylori in duodenal and gastric ulcer disease

A collection of the etiological theories, characteristics, and observations/phenomena of peptic ulcers in existing data

In this article, we compiled 13 etiological theories, 15 characteristics, and 81 observations/phenomena of peptic ulcers, reported in reproducible, peer-reviewed studies from the literature, to reflect the historical evolution of studies on peptic ulcers and to provide a multidisciplinary view of this disease. This data was collected during the systematic review of topics on peptic ulcers including genetics, etiology, epidemiology, psychology, anatomy, neurology, bacteriology, pathology, and clinical statistics. The data curated herein was extracted via application of recently published basic theories and methodologies.

Patients with duodenal ulcer have lower levels of serum cholesterol compared to other dyspeptic patients independently of Helicobacter pylori status

OBJECTIVE

The association between Helicobacter pylori (H. pylori) infection and serum lipid profile is still controversial. The aim of this study was to determine any possible relationship between H. pylori infection and the lipid profile of patients with upper gastrointestinal symptoms.

MATERIAL AND METHODS

Consecutively selected 20-70 year-old dyspeptic patients who had undergone esophagogastroduodenoscopy were evaluated for H. pylori infection using both the CLO test and Giemsa staining. Serum total cholesterol (C), HDL-C, LDL-C, apo-A1, apo-B and triglyceride levels were measured.

RESULTS

A total of 137 patients (median age 52.0 years) were studied. Total cholesterol levels were lower in H. pylori-infected patients than in H. pylori-negative patients (mean +/- SEM: 199.3 +/- 5.9 versus 212.6 +/- 4.6 mg/dl, p = 0.08). Patients with duodenal ulcer (DU) had significantly lower levels of all measured lipidemic parameters including cholesterol, with the exception of triglycerides, in comparison with either H. pylori-positive or -negative dyspeptic patients (cholesterol: 177.6 +/- 6.5 versus 214.6 +/- 4.2 mg/dl, p < 0.0001). However, there was no difference in the total cholesterol/HDL-C ratio between DU patients and the rest of the dyspeptic patients.

CONCLUSIONS

Among H. pylori-positive and H. pylori-negative patients there was no difference in lipid profile apart from a trend towards total cholesterol levels being lower in H. pylori-positive patients. However, cholesterol, HDL-C, LDL-C, apo-A and apo-B were all decreased in DU patients even though this reduction did not result in a fall in the total cholesterol/HDL-C ratio. The etiologic factor differentiating the lipid profiles among dyspeptics only in H. pylori-positive patients carrying a DU could be dietetic, microbial, genetic or a combination of all three.

Epidemiology of acute upper gastrointestinal bleeding

Acute upper gastrointestinal bleeding is an important emergency situation. Population-based epidemiology data are important to get insight in the actual healthcare problem. There are only few recent epidemiological surveys regarding acute upper gastrointestinal bleeding. Several surveys focusing on peptic ulcer disease showed a significant decrease in admission and mortality of peptic ulcer disease. Several more recent epidemiological surveys show a decrease in incidence of all cause upper gastrointestinal bleeding. The incidence of peptic ulcer bleeding remained stable. Peptic ulcer bleeding is the most common cause of upper gastrointestinal bleeding, responsible for about 50% of all cases, followed by oesophagitis and erosive disease. Variceal bleeding is the cause of bleeding in cirrhotic patients in 50-60%. Rebleeding in upper gastrointestinal bleeding occurs in 7-16%, despite endoscopic therapy. Rebleeding is especially high in variceal bleeding and peptic ulcer bleeding. Mortality ranges between 3 and 14% and did not change in the past 10 years. Mortality is increasing with increasing age and is significantly higher in patients who are already admitted in hospital for co-morbidity. Risk factors for peptic ulcer bleeding are NSAIDs use and H. pylori infection. In patients at risk for gastrointestinal bleeding and using NSAIDs, a protective drug was only used in 10%. COX-2 selective inhibitors do cause less gastroduodenal ulcers compared to non-selective NSAIDs, however, more cardiovascular adverse events are reported. H. pylori infection is found in about 50% of peptic ulcer bleeding patients. H. pylori should be tested for in all ulcer patients and eradication should be given.

Effective regimens for the treatment of Helicobacter pylori infection

Successful Helicobacter pylori eradication therapy remains a challenge in medical practice. Currently, a proton pump inhibitor-based triple therapy containing clarithromycin, amoxicillin or nitroimidazole for 7 days is the recommended first-line treatment approach with an expected eradication success rate of approximately 80%. As a second-line treatment option in the case of failure, a ranitidine bismuth citrate-based quadruple therapy is currently recommended curing another 80% of patients, leaving a subset of patients with persistent H. pylori infection. For these patients, promising rescue options have been evaluated including regimens that contain rifabutin, quinolones, furazolidone or high-dose amoxicillin. The role of susceptibility testing is still under discussion. It is not generally recommended prior to first-line treatment but guidelines propose a role for culture and antibiotic sensitivity testing after failure of the second attempt. Meanwhile, data on the geographic distribution of resistance pattern are available and may guide therapeutic decisions with regard to the combination of antibiotics chosen for the individual patients aiming at 100% cure rate in each individual patient.

Accelerated decline in Helicobacter pylori seroprevalence rate during the screen and treat project in Vammala, Finland, as demonstrated in 29- to 45-year-old pregnant women

The potential preventability of serious helicobacter-associated diseases - especially gastric cancer - has evoked interest in eradicating this pathogen from the population. We assessed the efficacy of the pioneering screen and treat intervention project in Vammala by studying helicobacter seroprevalence in pregnant women representing the normal population. Consecutive maternity clinic samples from native Finnish females at five different localities in 1995 (n=701) and 2000 (n=772) were investigated for class IgG H. pylori antibodies by enzyme immunoassay (Pyloriset EIA-G III, Orion Diagnostica, Espoo, Finland). In Vammala the change in helicobacter seroprevalence was -13%-units (between 1995 and 2000; p=0.0125, chi-square test) in > or =29-year-old females, +1.6%-units (difference statistically non-significant) in <29-year-old females, and -5.5%-units (difference statistically non-significant) in the whole study population. In the four reference localities studied, all the corresponding changes remained statistically non-significant. Thus, in Vammala the programme applied accelerated the decline of helicobacter infections in 29- to 45-year-old females and in 2000 the seroprevalence rate had also become significantly lower than that of the four reference communities combined (7.6% versus 13.5%, respectively, p=0.0433, chi-square test). The final outcome of the intervention project, i.e. the long-term effect of this decline on gastric cancer and peptic ulcer disease, remains to be evaluated.

Review article: Helicobacter pylori infection in peptic ulcer haemorrhage

In this overview, medical advice for routine clinical practice regarding peptic ulcer haemorrhage (PUH) is given, based on the extensive literature about Helicobacter pylori and the controversial results about the interaction of H. pylori infection and nonsteriodal anti-inflammatory drug (NSAID) use. PUH remains an important emergency situation with an incidence between 32 and 51/100 000 persons per year. There is a high association between H. pylori infection and peptic ulcer disease. The association between H. pylori infection and PUH is less clear, but a strong argument for the aetiological role is the fact that eradication of H. pylori decreases recurrence of bleeding. NSAID use is another important risk factor for PUH. H. pylori infection and NSAID use seem to act independently, although some studies show a synergistic interaction while other studies report that H. pylori is protective against the development of PUH in NSAID users. All patients with PUH should be tested for H. pylori infection, regardless of the use of NSAIDs. Because invasive tests are less sensitive in PUH patients, negative tests in patients with no other risk factors should be confirmed by serology or urea breath test (UBT). Eradication therapy with a proton pump inhibitor or ranitidine bismuth citrate-based triple therapy should be given to all H. pylori-positive patients. Only for nonaspirin-NSAID users does the effect of eradication therapy on the healing of gastric ulcers remain controversial, but currently we also advise eradication of H. pylori in this subgroup. After eradication therapy, acid-suppressant therapy is advised to heal the ulcer. The success of eradication should always be confirmed because of the risk of recurrence of peptic ulcer disease and bleeding in H. pylori-infected patients.

New inhibitors of Helicobacter pylori urease holoenzyme selected from phage-displayed peptide libraries

Urease is an important virulence factor for Helicobacter pylori and is critical for bacterial colonization of the human gastric mucosa. Specific inhibition of urease activity has been proposed as a possible strategy to fight this bacteria which infects billions of individual throughout the world and can lead to severe pathological conditions in a limited number of cases. We have selected peptides which specifically bind and inhibit H. pylori urease from libraries of random peptides displayed on filamentous phage in the context of pIII coat protein. Screening of a highly diverse 25-mer combinatorial library and two newly constructed random 6-mer peptide libraries on solid phase H. pylori urease holoenzyme allowed the identification of two peptides, 24-mer TFLPQPRCSALLRYLSEDGVIVPS and 6-mer YDFYWW that can bind and inhibit the activity of urease purified from H. pylori. These two peptides were chemically synthesized and their inhibition constants (Ki) were found to be 47 microM for the 24-mer and 30 microM for the 6-mer peptide. Both peptides specifically inhibited the activity of H. pylori urease but not that of Bacillus pasteurii.

Review: Helicobacter pylori. Current issues and new directions

The present review outlines current management issues and controversies related to Helicobacter pylori infection. Clearance of this infection markedly reduces the likelihood of duodenal and gastric ulcer recurrence and may result in the regression of low grade primary gastric lymphoma. Recent therapeutic advances have seen the development of simpler drug regimens to treat H. pylori that have fewer side effects and are shorter in duration. Clearance of the infection can be achieved in 80-95% of patients treated, depending on the drug regimen used, compliance with medications and antibiotic sensitivity. In developed nations reinfection is uncommon after successful treatment. Data do not currently support treatment of this infection for non-ulcer dyspepsia or for the prevention of gastric cancer, although whether certain individuals or populations may benefit from such treatment remains to be clarified.