Campylobacter pylori and ulcer disease--a causal connection?

Impairment of salivary mucin production resulting in declined salivary viscosity during naproxen administration as a potential link to upper alimentary tract mucosal injury

OBJECTIVES:

Nonsteroidal anti-inflammatory drugs (NSAIDs) contribute to the esophageal mucosal injury through its direct topical impact on the luminal aspect of the surface epithelium. Its indirect, systemic impact, however, on salivary component of the esophageal pre-epithelial barrier remains to be explored. Therefore, salivary mucin secretion and viscosity at baseline and during naproxen-placebo, as well as naproxen-rabeprazole, administration were investigated.

METHODS:

Twenty-one asymptomatic volunteers were included in this double-blind, placebo-controlled, crossover designed study. Salivary samples were obtained in basal and pentagastrin-stimulated conditions (6 mg/kg s.c.) mimicking the food-stimulated conditions. Patients received 7 days of naproxen-placebo or naproxen-rabeprazole with a 2-week washout period in between. Salivary mucin content and viscosity were measured before and after treatment using periodic acid/Schiff's methodology and Cone/Plate Digital Viscometer, respectively.

RESULTS:

The rate of salivary mucin secretion in basal condition declined by 32% during administration of naproxen-placebo (11.3±1.7 vs. 16.8±3.3 mg/h). Salivary mucin secretion in pentagastrin-stimulated condition declined significantly (by 34%) during the administration of naproxen-placebo (13.6±1.5 vs. 20.7±3.0 mg/h; P<0.05). Viscosity significantly decreased after naproxen-placebo administration in basal (by 60%) and stimulated conditions (by 56%) (P<0.001). Coadministration of rabeprazole at least partly restored the naproxen-induced decline of salivary mucin in basal condition (by 8%), and pentagastrin-stimulated conditions (by 30%).

CONCLUSIONS:

A significant decline of salivary mucin and viscosity during administration of naproxen may at least partly explain a propensity of patients on chronic therapy with NSAIDs to the development of esophageal mucosal injury and complications. In addition the trend to restorative capacity of rabeprazole on the quantitative impairment of salivary mucin during administration of naproxen may potentially translate into its tangible clinical benefit but it requires further investigation.

Patients with Helicobacter pylori positive and negative duodenal ulcers have distinct clinical characteristics

AIM: To assess the clinical characteristics of Helicobacter pylori (H pylori) negative duodenal ulcer.

METHODS: Patients with an endoscopic diagnosis of duodenal ulcer between 1996 and 2002 were included in the present study. Patients were considered to be negative for H pylori, if both histological examination and rapid urease test of biopsy specimens were negative. A comparison was made between patients with H pylori positive and negative duodenal ulcers.

RESULTS: A total of 1 343 patients were studied. Their mean age was 54.7±0.5 years. There was a male preponderance (M:F = 2.5:1). Three hundred and ninety-eight patients (29.6%) did not have H pylori infection. The annual proportion of patients with H pylori negative duodenal ulcers increased progressively from 1996 to 2002. On multivariate analysis, patients with H pylori negative duodenal ulcer were more likely to be older, have concomitant medical problem, pre-existing malignancy, recent surgery, underlying sepsis, or taken non-steroidal anti-inflammatory drugs. In terms of clinical presentations, patients with H pylori negative duodenal ulcer were more likely to present with bleeding, multiple ulcers and larger ulcers.

CONCLUSION: The proportion of patients with H pylori negative duodenal ulcers is on the rise because of a continued drop in incidence of H pylori positive duodenal ulcers in recent years. Such patients have distinct clinical characteristics and it is important to ascertain the H pylori status before starting eradication therapy.

Restorative impact of rabeprazole on gastric mucus and mucin production impairment during naproxen administration: its potential clinical significance

Rabeprazole augments gastric mucus and mucin production in humans. However, its potential restorative impact on gastric mucus and mucin production impairment, resulting from administration of naproxen, remained to be explored. Therefore, we measured the content of mucus and mucin in gastric juice (GJ) before and after administration of naproxen with rabeprazole or placebo. The study was approved by HSC at KUMC and conducted in 21 asymptomatic, H. pylori-negative volunteers in a double-blind, placebo-controlled, crossover design. The content of gastric mucus in GJ, after exhaustive dialysis and complete lyophilization, was assessed gravimetrically, whereas the content of mucin was measured after its purification with equilibrium density-gradient ultracentrifugation in CsC1. Gastric mucus secretion during administration of naproxen with placebo declined significantly both in basal (by 44%; P < 0.001) and in pentagastrin-stimulated (by 35%; P < 0.001) conditions. Coadministration of rabeprazole significantly restored the naproxen-induced impairment in mucus production in basal conditions (by 47%; P < 0.01) and by 22% during stimulation with pentagastrin. Gastric mucin secretion during naproxen/placebo administration also declined significantly in both basal (by 39%; P < 0.01) and stimulated (by 49%; P = 0.003) conditions. Rabeprazole also significantly restored the naproxen-induced decline of gastric mucin output during pentagastrin-stimulated conditions (by 67%; P = 0.003) and by 40% in basal conditions (P = 0.05). The restorative capacity of rabeprazole on the quantitative impairment of gastric mucus and mucin during administration of naproxen may translate into a clinical benefit of protection of the upper alimentary tract from NSAID-related mucosal injury.

Significant enhancement of gastric mucin content after rabeprazole administration: its potential clinical significance in acid-related disorders

Rabeprazole is the only proton pump inhibitor that enhances the content of gastric mucin in experimental animals. We have studied, therefore, the effect of rabeprazole on the content of gastric mucin, mucus, and its viscosity in 21 asymptomatic volunteers in a double-blind study. The mucus content during rabeprazole administration significantly increased both in pentagastrin-stimulated (3.36 +/- 0.39 vs 1.50 +/- 0.32 mg/ml, P < 0.001) and basal (3.31 +/- 0.38 vs 2.28 +/- 0.36 mg/ml, P < 0.01) conditions. The content of mucin during rabeprazole was 2.6-fold (0.96 +/- 0.08 vs 0.36 +/- 0.06 mg/ml, P < 0.0001) and 41% (0.82 +/- 0.09 vs 0.58 +/- 0.09 mg/ml, P < 0.05) higher in stimulated and basal conditions, respectively. The viscosity of gastric juice during rabeprazole administration was also significantly higher both in stimulated (P < 0.01) and basal (P < 0.05) conditions. In conclusion, the unique pharmacological property of rabeprazole, significantly augmenting production of gastric mucus and mucin, may translate to additional clinical benefits in protecting the upper alimentary tract mucosa during the acid-related challenge.

Influence of the NIH Consensus Conference on Helicobacter pylori on physician prescribing among a Medicaid population

OBJECTIVES

In February 1994, an National Institutes of Health (NIH) Consensus Development Conference panel unequivocally recommended antimicrobial therapy to eradicate Helicobacter pylori in the treatment of peptic ulcer disease. The goal of this study was to determine if these recommendations resulted in a change in physician prescribing among an underserved population.

METHODS

Computerized Pennsylvania Medicaid data from January 1993 through February 1996 were used to evaluate prescribing patterns in the year before and 2 years after the NIH conference. An interrupted time series model, based on 12,737 outpatient peptic ulcer disease encounters, assessed the impact of the conference in influencing physician prescribing.

RESULTS

The prescription of antimicrobial agents for the treatment of peptic ulcer disease significantly increased across the study period, from 6.5% in January 1993 to 10.2% in February 1996. Similarly, the prescription rate for the proton pump inhibitor, omeprazole, significantly increased from 9.4% in January 1993 to 25.6% in February 1996. Neither trend, however, could be attributed to the NIH Consensus Development Conference. Stratification by physician specialty, ulcer type, nonsteroidal anti-inflammatory drug use, and patient demographics did not affect these results. The traditional treatment approach, using H2-receptor antagonists, remained the preferred pharmacotherapy (72% of all prescriptions).

CONCLUSIONS

Two years after the highly publicized NIH conference on the eradication of Helicobacter pylori, antimicrobial agents were not widely prescribed among the Pennsylvania Medicaid population. In treating this underserved population, physicians do not appear to be using recommendations developed by an NIH expert panel based on recent scientific advances.

Helicobacter pylori in duodenal ulcer patients with idiopathic gastric acid hypersecretion

Thirty-three consecutive patients with idiopathic gastric acid hypersecretion (defined as a basal acid output > 10.0 meq/hr with a normal fasting serum gastrin level and negative secretin stimulation test) who were being treated for duodenal ulcer disease and other acid-peptic disorders were evaluated for the presence of Helicobacter pylori by means of a rapid urease test. Fourteen patients had duodenal ulcer and 19 had other acid-peptic disorders (gastroesophageal reflux in 14, including six with Barrett's esophagus; four with nonulcer dyspepsia; and one with erosive gastritis). Helicobacter pylori was present in 12 of the 14 ulcer patients (86%) compared to only two of the 19 nonulcer patients (11%) (P < 0.0001). The distribution of basal acid output for patients with duodenal ulcer was similar to that for nonulcer patients, and no significant difference in the mean basal acid output was found among Helicobacter pylori-positive compared to Helicobacter pylori-negative patients. Seven of the duodenal ulcer patients with a basal acid output greater than 15.0 meq/hr were Helicobacter pylori-positive, suggesting that the organism can withstand even extreme levels of gastric acidity. In conclusion, this study demonstrates that the prevalence of Helicobacter pylori infection in patients with duodenal ulcer disease associated with idiopathic gastric acid hypersecretion is not different from a majority of ulcer patients with normal acid secretory profiles and offers additional evidence that extreme levels of gastric acid are not bactericidal for the organism.

Changing trends in perforated peptic ulcer during the past 45 years

Since 1944 there has been a dramatic change in the pattern of admissions for perforated peptic ulcer (PPU) to the Royal Newcastle Hospital, the main teaching hospital of the Hunter Region, Australia. Between 1944 and 1950, females accounted for 6% of all perforations; since then the proportion of females admitted with this complication has risen to 32%. Simultaneously, the modal age for PPU has shifted from the fifth to the seventh decade and the ratio of gastric to pyloroduodenal perforations has fallen from 1.1:1 to 0.6:1. No good explanation for this change in the natural history of PPU, also noted elsewhere, is evident.

Medical treatment of duodenal ulcer: acid inhibition or Helicobacter pylori eradication?

To ascertain whether acid inhibition or Helicobacter pylori (HP) colonization is the decisive factor in the healing of duodenal ulcer, we treated 54 patients with famotidine and carried out long-term follow-up. Helicobacter pylori colonization was found in 70.4% of patients before treatment. There were no differences in the pre-treatment characteristics between patients with HP positive or HP negative ulcers. The 4-week and 8-week healing rates after famotidine treatment were 72.5% and 82.4% respectively. No difference in HP colonization was found between patients with ulcer healed and those with ulcer not healed (78.4% vs 64.3% at 4th week and 77.3% vs 71.4% at 8th week, P greater than 0.05). In patients with ulcer healed at 4th week, the intragastric pH was raised significantly and the antral acute inflammation was less severe than those with ulcer not healed. Ulcer recurrence was found in 76.9% of patients within 1 year, but there was no difference in ulcer recurrence between the patients with positive or negative HP colonization at the time of ulcer healing. Our results suggest that duodenal ulcer healing and recurrence are closely related to acid inhibition rather than to HP colonization.

Helicobacter pylori associated chronic gastritis and peptic ulceration in patients taking non-steroidal anti-inflammatory drugs

Helicobacter pylori is now recognized as a frequent cause of histological chronic gastritis, and this has radically changed our understanding of this common condition. In the light of these developments, the traditional view that non-steroidal anti-inflammatory drugs are one of the common 'environmental' causes of chronic gastritis has been re-examined. Gastric mucosal biopsies have been studied from 430 patients undergoing routine upper gastrointestinal endoscopy, 99 of whom had recently been taking non-steroidal anti-inflammatory drugs. No significant association was found between the use of these drugs and either the presence of chronic gastritis or the frequency of colonization with H. pylori, although there was a strong association (P less than 0.0001) between H. pylori and gastritis. Non-steroidal anti-inflammatory drugs appear, however, to modify the inflammatory process in the gastric body, leading to a lower frequency of atrophic gastritis (P less than 0.05). The majority of peptic ulcers were associated with H. pylori irrespective of non-steroidal anti-inflammatory drug use, but there was a higher frequency of H. pylori negative ulceration in the patients who had used these agents (P less than 0.04). Peptic ulceration was uncommon in the absence of either H. pylori or recent non-steroidal anti-inflammatory drug use.