Effect of Helicobacter pylori on serum pepsinogen I and plasma gastrin in duodenal ulcer patients

Alteration of correlation between serum pepsinogen concentrations and gastric acid secretion after H. pylori eradication

PURPOSE

The measurement of serum pepsinogens is clinically useful to represent gastric acid secretion. Since both serum pepsinogens and gastric acid secretion are considerably altered by H. pylori eradication, the correlation between these two parameters could be different prior to and after eradication. In this study, we investigated the correlation between the two parameters prior to and after eradication.

METHODS

One hundred eighteen H. pylori-positive patients with peptic ulcers or chronic gastritis were enrolled in this retrospective analysis. In all participants both the measurement of serum pepsinogens and the determination of gastric acid secretion were performed prior to and at 1 month after successful eradication. In 85 subjects, the same assessments were repeated at 7 months. Correlations between serum pepsinogens and gastric acid secretion were assessed using linear regression analysis.

RESULTS

The pepsinogen I/II ratio (r = 0.56) was a better indicator of gastric acid secretion in H. pylori-infected subjects than pepsinogen I itself (r = 0.31). Eradication of H. pylori altered the association, causing pepsinogen I (r = 0.55) to become a better indicator of gastric acid secretion compared with the pepsinogen I/II ratio (r = 0.40) at 1 month after eradication, followed by similar tendencies at 7 months.

CONCLUSION

Using different serum biomarkers (pepsinogen I/II ratio prior to eradication or pepsinogen I after eradication), the measurement of serum pepsinogens is useful for predicting the individual gastric acid secretion level not only in H. pylori-infected subjects, but also in subjects with histories of eradication of the infection.

Usefulness of serum pepsinogens in Helicobacter pylori chronic gastritis: relationship with inflammation, activity, and density of the bacterium

We sought to study the relationship between serum pepsinogens and different histopathologic features of Helicobacter pylori-related chronic gastritis. One hundred forty-nine consecutive dyspeptic patients underwent endoscopy with biopsies; serum pepsinogens I and II were measured by immunoassay. Serum levels of pepsinogens (sPG) were significantly correlated with H. pylori density both of the corpus (sPGI: r = 0.32, P < .001; sPGII: r = 0.56, P < .001) and antrum (sPGI: r = 0.41, P < .001; sPGII: r = 0.43, P < .001) as well as with chronic inflammation (sPGI: r = 0.26, P < .001; sPGII: r = 0.49, P < .001) and activity (sPGI: r = 0.38, P < .001; sPGII: r = 0.50, P < .001) in the antrum. Only sPGII was correlated with chronic inflammation (r = 0.44, P < .001) and activity (r = 0.40, P < .001) in the corpus. SPGI was inversely correlated with atrophy (r = -0.33, P < .001) and intestinal metaplasia (r = -0.37, P < .001) in the corpus. sPGII levels could be considered as markers of gastric inflammation all over in the stomach. sPGI levels are inversely related to atrophic body gastritis.

Problem of distinguishing false-positive tests from acute or transient Helicobacter pylori infections

BACKGROUND

Reliable detection of acute Helicobacter pylori infections remains problematic. The high prevalence of false-positive non-invasive tests in low H. pylori prevalence populations makes identification of acute and transient infections difficult.

METHODS

We explored the use of serum pepsinogens (PG) for diagnosis of acute infection in patients following H. pylori challenge such that the onset of the infection was known. We then compared those findings to a group of children with presumed acute infections defined as a positive urea breath test (UBT) and negative IgG serology.

RESULTS

We examined the pattern and calculated cut-off values of PG levels in 18 adult volunteers with known acute H. pylori infection. We then compared the results with sera from nine symptomatic children with presumed acute H. pylori infection and a matched control group of nine children who did not meet criteria for acute H. pylori infection. In acute infection, both PGI and II levels increased following H. pylori infection reaching a peak by 2 weeks post-infection. The frequency of a positive test defined as a value > mean +2 SD was 17, 71, and 94% at week 1, 2, and 4 post-infection, respectively. Only one child with presumed acute H. pylori infection had an elevated serum PGI and one had an elevated PGII. Five of the children had follow-up UBTs and four were negative consistent with the diagnosis of false-positive UBT. H. pylori infection was confirmed in the child with an elevated PGI level.

CONCLUSIONS

These data suggest that a single positive noninvasive test in populations of low prevalence is most likely a false-positive result. This suggests that a single positive test requires confirmation preferably using a test that measures a different parameter (e.g., UBT confirmed by stool antigen test). It appears that most "transient"H. pylori infections are diagnosed on the basis of false-positive tests. PG levels are possible candidates as the confirmatory test.

[Basal concentrations of gastrin and pepsinogen I and II in gastric ulcer: influence of Helicobacter pylori infection and usefulness in the control of the eradication]

AIM

To study the influence of Helicobacter pylori eradication on basal gastrin and pepsinogen I and II levels in patients with gastric ulcer over a 1-year follow-up period, and to assess the usefulness of these values in confirming H. pylori eradication after treatment.

METHODS

Fifty-six patients with gastric ulcer and H. pylori infection were prospectively studied. At the beginning of the study, endoscopy with biopsies for histologic examination and urease testing was carried out, as were 13C-urea breath test and blood samples for determination of gastrin and pepsinogen I and II values by radioimmunoassay and serology. Histologic study, 13C-urea breath test and laboratory determinations were repeated at months 1, 6 and 12 after completion of eradication treatment.

RESULTS

H. pylori infection was eradicated in 82.1% of patients. In patients with successful H. pylori eradication, the initial mean gastrin value was 75.5 +/- 39.1 pg/ml, while at 1 month after treatment this value decreased to 49.2 +/- 21 pg/ml (p < 0.0001). No further reductions were noted. Initial pepsinogen I and II values were 104 +/- 58 and 15.8 +/- 10 ng/ml, respectively, whereas at month 1 after treatment these values were 77 +/- 42 and 7.3 +/- 4 ng/ml, respectively (p < 0.0001) and were 72 +/- 41 and 6.7 +/- 3 ng/ml respectively at month 6 (p < 0.01); no further variations were observed thereafter. The area under the ROC curve which reveals eradication through reductions in hormonal values was 0.70 for gastrin, 0.78 for pepsinogen I, 0.93 for pepsinogen II and 0.92 for the pepsinogen I/II ratio. At months 6 and 12 after treatment completion, differences in mean gastrin and pepsinogen I and II values between the patients with normal histologic findings and those with chronic gastritis were significant (p < 0.05).

CONCLUSIONS

a) H. pylori eradication is associated with an early fall in basal gastrin values and a progressive decrease in basal pepsinogen I and II values. b) In patients with gastric ulcer, determination of the decrease in basal pepsinogen II levels is a useful and early non-invasive method for confirming eradication. c) Determination of gastrin and pepsinogen I and II values may be useful for assessing improvement in gastritis 6 months after treatment completion.

Transfer of metronidazole to gastric juice: impact of Helicobacter pylori infection and omeprazole

BACKGROUND

The effects of Helicobacter pylori infection associated with inhibition of gastric acid secretion on the distribution of medications used for H. pylori eradication are poorly understood. The aim of this study was to investigate the effects of a 7-day administration of 20 mg omeprazole on the transfer of metronidazole from plasma to the gastric juice of individuals with and without H. pylori infection.

METHODS

Fourteen H. pylori-positive and 14 H. pylori-negative male volunteers were enrolled in a study with an open, randomized, two-period crossover design with a 21-day washout period between phases. Plasma, salivary, and gastric juice concentrations of metronidazole in subjects with and without omeprazole treatment were measured with reversed-phase high-performance liquid chromatography/liquid chromatography.

RESULTS

Metronidazole peak concentration (Cmax) was similar in plasma and saliva and was approximately threefold higher in gastric juice in all groups. Omeprazole treatment increased gastric pH and did not affect metronidazole Cmax or the time required for this to be reached (tmax) in plasma, saliva, or gastric juice. However, omeprazole significantly reduced metronidazole transfer from plasma to gastric juice in H. pylori-positive but not H. pylori-negative subjects, as shown by statistical analysis of AUC(0-2 h).

CONCLUSION

Short-term treatment with omeprazole in H. pylori- positive volunteers reduces the amount of metronidazole transferred from plasma to gastric juice. This seems to occur in a pH-independent form.

Host determinants of Helicobacter pylori infection and its clinical outcome

Greater than one-half of the world's population harbors Helicobacter pylori. The majority of infected individuals, however, remain asymptomatic, with only 10% to 20% developing diseases, including peptic ulcer disease, gastric cancer, and gastric mucosa-associated lymphoid tissue lymphoma. This article reviews host factors that may predispose an individual to both the acquisition of H. pylori infection and subsequent clinical outcome. Individuals with specific blood group antigens and human leukocyte antigen genotypes may be more susceptible to H. pylori infection. Additional factors, such as the age of acquisition, the host immune response, the site of infection, acid secretion, and interactions with nonhost factors (including bacterial virulence factors and environmental influences) may play a role in determining clinical outcome. Further investigation is required to clarify the mechanisms by which these interactions occur and, more critically, to determine their relative importance. This knowledge will enable the identification of individuals at risk of developing clinical disease with H. pylori infection.

Noninvasive evaluation of Helicobacter pylori therapy: role of fasting or postprandial gastrin, pepsinogen I, pepsinogen II, or serum IgG antibodies

OBJECTIVE

We evaluated the potential value of a change in serum IgG antibodies, fasting or meal-stimulated gastrin levels, and pepsinogen I (PGI) or pepsinogen II (PGII) levels for identifying Helicobacter pylori (H. pylori) status after antibiotic therapy.

METHODS

A total of 32 men and one woman with peptic ulcer disease and documented H. pylori infection were enrolled. Fasting and 30-min postprandial blood samples were obtained at 0, 2, 7, 11, 17, 23, 27, and 39 wk of the study and were analyzed for the factors evaluated.

RESULTS

Treatment was successful in 25 patients and failed in seven. Serum IgG antibodies, meal-stimulated gastrin, and both fasting and meal-stimulated pepsinogen I and II levels fell throughout the study, and pepsinogen I:II ratios increased in those whose infection was cured. The mean levels at wk 0 versus wk 7 were: fasting gastrin (fmol/ml) 12.4 and 11, meal-stimulated gastrin 26.5 and 15.4, PGI (ng/ml) 83.7 and 59, PGII (ng/ml) 24.5 and 13.6, PGI/PGII 3.5 and 4.7, and enzyme-linked immunosorbent assay value 4.8 and 4.55. The sensitivity, specificity, and positive and negative predictive values for the data analyzed using different percent changes (e.g., 80%, 50%, and 20%) were calculated. The specificity and sensitivity remained <80% at all time points.

CONCLUSIONS

Despite a significant fall in serum markers of H. pylori infection in groups of individuals, no marker tested could be used to reliably determine posttherapy H. pylori status for individual patients.

Stimulation of pepsinogen release from chief cells by Helicobacter pylori: evidence for a role of calcium and calmodulin

To define the mechanisms by which Helicobacter pylori stimulates pepsinogen secretion, the in vitro release of pepsinogen was studied using a preparation of pig chief cell monolayers. Helicobacter pylori induced a time- and concentration-dependent release of pepsinogen into the medium, with about a three-fold increase in pepsinogen secretion over controls found after 45 min of incubation. 3x10(7) H. pylori produced 50% of the maximal response found at a H. pylori count of 2x10(8). The action of H. pylori did not depend on the presence of the vacuolating toxin (vacA) and the cytotoxin-associated protein (cagA). Dibutyryl-cAMP and the phorbol ester 12-O-tetradecanoylphorbol-13-acetate also markedly stimulated pepsinogen secretion and enhanced the stimulatory effect of H. pylori. Helicobacter pylori-stimulated pepsinogen release was inhibited by lanthanum and the calmodulin antagonist W-7, but not by the L-type Ca2+ channel blocker nifedipine, TMB-8, an agent that blocks the release of Ca2+ from intracellular stores, the protein kinase C inhibitor staurosporine and the protein kinase A inhibitor H-8. It is suggested that H. pylori directly stimulates pepsinogen release from gastric chief cells and that this effect is mediated via the calcium/calmodulin messenger branch.

Changes in serum pepsinogen, gastrin, and immunoglobulin G antibody titers in helicobacter pylori-positive gastric ulcer after eradication of infection

There are no studies of changes in immunoglobulin G (IgG) titers to Helicobacter pylori, serum pepsinogen, and gastrin in patients with H. pylori-positive gastric ulcers. We investigated the effect of therapy for H. pylori-positive gastric ulcer on IgG titers to H. pylori, serum pepsinogen I and II, and gastrin. Thirty-six patients with H. pylori-positive gastric ulcer were treated with lansorazole and antibiotics for 2 weeks. Serum pepsinogen I and II concentrations, serum gastrin, and IgG titers to H. pylori were measured before treatment and then at 4 and 12 weeks after stopping the treatment. The presence or eradication of H. pylori was determined using the rapid urease test and by histologic H. pylori staining. For 19 patients in whom H. pylori had been successfully eradicated, the pepsinogen I/II ratio increased, pepsinogen II levels decreased, and the anti-H. pylori IgG decreased compared with the results from before therapy and with those from 4 and 12 weeks after therapy. Gastrin levels decreased compared with pretreatment results and those from 4 weeks after the end of treatment. In 17 patients in whom the therapy failed to eradicate H. pylori infection, there were no sequential significant changes in the pepsinogen I/II ratio or in the levels of pepsinogen I, pepsinogen II, anti-H. pylori IgG, and gastrin. A decrease in the serum levels of the IgG antibody to H. pylori and gastrin and also an increase in the pepsinogen I/II ratio could be used as predictors for the eradication of H. pylori infection in gastric ulcer.

The clinical usefulness of serum pepsinogens, specific IgG anti-HP antibodies and gastrin for monitoring Helicobacter pylori treatment in older people

OBJECTIVE

To evaluate the clinical usefulness of Pepsinogen A (PGA) and C (PGC), PGA/PGC ratio, gastrin, and specific IgG anti-HP antibodies (anti-HP Ab) in monitoring the effect of cure for Helicobacter pylori (HP) infection in older people.

DESIGN

We studied the changes in serum parameters (PGA, PGC, PGA/PGC ratio, gastrin and anti-HP Ab) in older patients before and 2 months after stopping therapy for the cure of HP infection.

PATIENTS

Eighty-eight older patients (M = 43, F = 45, mean age = 73.3, range = 60-89) with chronic gastritis (42), gastric ulcer (14) or duodenal ulcer (32) were found HP-positive by histology of gastric antral and body biopsies and the rapid urease test.

INTERVENTIONS

Two different associations of antibiotics and antiulcer drugs (omeprazole, metronidazole, azithromycin, or clarithromycin) for 2-4 weeks.

MEASUREMENTS

At the beginning of the study and 2 months after treatment withdrawal, the subjects were studied by upper G.I. endoscopy with at least two antral and two body gastric biopsies (Giemsa stain and rapid urease test for HP); serum PGA (RIA method, microgram/mL), PGC (RIA method, microgram/mL), PGA/PGC ratio, gastrin (RIA method, picogr/mL), and anti-HP Ab (ELISA method, Biolife, MU/mL) were also determined. Statistical analysis was based on either the Wilcoxon test, for paired data, the chi-square test, the Kruskal Wallis test, or the Mann-Whitney test for unpaired data. The choice of the best cut-off value in the different parameters was performed by receiver operating characteristics curves (ROC) and by Youden index. The correlation between HP density in the gastric mucosa and gastritis activity was verified by Spearman rank correlation test.

RESULTS

After therapy, 56/88 patients proved HP-negative (HP-eradicated: M = 30, F = 26, mean age = 73.0, range = 60-87 years), whereas 32/88 were not cured (HP-persistent: M = 13, F = 19, mean age = 73.0, range = 60-89 years). After therapy, in HP-eradicated cases, a statistically significant change was found in anti-HP Ab (75.23 +/- 8.94 vs 47.32 +/- 5.26, P < .001), PGC (21.58 +/- 1.97 vs 14.34 +/- 1.75, P < .001), and PGA/PGC ratio (8.46 +/- 0.68 vs 11.54 +/- 0.89, P < .001), but not in PGA and gastrin. On the other hand, in HP-persistent cases, anti-HP Ab, PGA, PGC, PGA/ PGC ratio and gastrin did not change after therapy. The sensitivity and specificity were, respectively, 0.62 and 0.56 for anti-HP Ab and 0.75 and 0.56 for the PGA/PGC ratio, which demonstrated the best diagnostic accuracy (68%).

CONCLUSIONS

The eradication of HP from the stomach of older patients induces a rapid and significant decrease in serum levels of IgG anti-HP antibodies and PGC, with an increase in PGA/PGC ratio but not in gastrin. Unchanged serum levels of IgG anti-HP antibodies, PGC, and PGA/PGC ratio 2 months after completing HP eradication therapy are indicative of ongoing HP infection. The PGA/PGC ratio showed the best diagnostic accuracy among serum measures tested.

Verification of decreased basal and stimulated serum pepsinogen-I levels is a useful non-invasive method for determining the success of eradication therapy for Helicobacter pylori

BACKGROUND

We wanted to demonstrate the effect of Helicobacter pylori eradication on basal and stimulated pepsinogen-I levels in duodenal ulcer patients and to verify whether modification of such levels is a useful method for determining the success of eradication therapy.

METHODS

Thirty-two patients (24 men; mean age, 45 years) with active duodenal ulcer were studied. In all patients three biopsy specimens were taken from the duodenal bulb, gastric antrum, body and fundus for microbiologic and histologic examination. Triple therapy consisting of bismuth, metronidazole, and tetracycline was administered. Endoscopy was repeated 1 month after completing therapy, and biopsy specimens were again taken from the gastric antrum and body. Serum samples were taken at initial and repeat endoscopies, to measure basal and stimulated (120 min) pepsinogen-I levels after injection of pentagastrin.

RESULTS

H. pylori was eradicated in 26 patients (81%). Significant histologic improvement, in both the antrum and body, was observed (p < 0.001). Basal pepsinogen-I levels (mean and 95% confidence interval) at diagnosis and after eradication were 106 (92-119) and 87 (74-100) ng/ml, respectively (P < 0.001). Similarly, stimulated pepsinogen-I levels (integrated values) decreased from 4790 (4199-5381) before therapy to 3970 (3383-4557) ng/ml.min after eradication (P < 0.001). Pepsinogen I levels did not change in patients in whom H. pylori was not eradicated. The area under the receiver operating characteristic curve for decreased basal and stimulated pepsinogen-I levels was 0.77 (SE, 0.09) and 0.79 (SE, 0.1), respectively.

CONCLUSION

H. pylori eradication in duodenal ulcer patients was associated with a significant decrease in basal and stimulated pepsinogen-I levels. Measurement of these levels could determine how successful response to therapy has been in both the eradication and resolution of associated gastritis. Other advantages of this procedure are that it has low cost and results are evident at an early stage.

Helicobacter pylori infection and serum pepsinogen I concentration in peptic ulcer patients: effect of bacterial eradication

OBJECTIVES

In order to test the hypothesis that H. pylori infections in the gastric antrum increase pepsinogen I release, fasting serum pepsinogen I concentrations were compared in peptic ulcer patients with and without H. pylori infection. A randomized prospective study was performed to determine whether the increased serum pepsinogen I concentrations associated with H. pylori infection respond to treatment that eradicates H. pylori.

METHODS

Fasting serum pepsinogen I concentrations were measured by RIA in 736 patients with endoscopically and histologically confirmed benign peptic ulcer with and without H. pylori infection. Out of 511 patients with H. pylori infection, 110 patients (group 1) were randomly selected and were treated with metronidazole and tripotassium dicitrato bismuthate combined with ranitidine and antacid, and 97 patients (group 2) were treated only with ranitidine and antacid. The third group, 54 patients free of H. pylori infection, was designed to evaluate the influence of H2-receptor antagonist and antacid on the change of pepsinogen I. Fasting pepsinogen I concentration and H. pylori status were compared before and after the treatment.

RESULTS

Patients infected by H. pylori (gastric ulcer 208, duodenal ulcer 303; total 511) had significantly higher fasting serum pepsinogen I concentrations than H. pylori negative patients (gastric ulcer 110, duodenal ulcer 115; total 225). Mean pepsinogen I level of the former was 124.3 +/- 46.9 and that of the latter was 77.9 +/- 25.8 ng/ml. (p < 0.0001). The difference in serum pepsinogen I concentrations according to the location of ulcer crater was significant only in non-infected subjects e.g., mean pepsinogen I level H. pylori-negative gastric ulcer was significantly lower than that of H. pylori-negative duodenal ulcer patients. H. pylori was eradicated in all the patients who had received antibacterial therapy for 4 weeks and serum pepsinogen I concentrations were significantly decreased from 129.8 +/- 43.0 to 82.4 +/- 24.0 ng/ml after eradication of the organism. (p < 0.0001) In contrast, H. pylori-positive patients who had not received antibacterial therapy were still infected at the completion of the study and there was no significant change in the serum pepsinogen I concentrations after the treatment (120.8 +/- 40.9 vs 126.3 +/- 40.4 ng/ml). (p > 0.57) None of the patients who were initially H. pylori-negative has been reinfected during the period of the study and their serum pepsinogen I concentrations were not changed. (pre-treatment value 75.1 +/- 8.0; post-treatment value 77.3 +/- 24.5 mg/ml) (p < 0.75) Four-to six-week therapy of H2-receptor antagonist and antacid did not exert any influence on serum pepsinogen I concentrations.

CONCLUSIONS

On the basis of our results, we have confirmed that the chronic infection of H. pylori of gastric antrum in peptic ulcer patients causes increased pepsinogen I release into the circulation, and eradication of the organism results in significant fall in serum pepsinogen I concentrations.

Helicobacter pylori infection is associated with low antral somatostatin content in young adults. Implications for the pathogenesis of hypergastrinemia

BACKGROUND

Recent studies on the role of Helicobacter pylori in the pathogenesis of duodenal ulcers have focused on the mechanism by which H. pylori infections cause exaggerated gastrin release.

METHODS

We determined meal-stimulated serum gastrin concentrations and antral somatostatin content in 24 asymptomatic volunteers (6 H. pylori-infected, 18 H. pylori-uninfected). Somatostatin content was determined by radioimmunoassay in biopsy specimens obtained from the antrum.

RESULTS

Fasting and integrated 2-h gastrin concentrations were significantly higher in H. pylori-positive volunteers than in H. pylori-negative volunteers (fasting, 111 +/- 16.3 pmol/l versus 53.4 +/- 3.5 pmol/l; p < 0.05; integrated 2-h, 267 +/- 41.2 pmol/l versus 70.1 +/- 2.1 pmol/l; p < 0.01). Antral somatostatin content was 0.764 +/- 0.173 ng/mg and 2.931 +/- 0.414 ng/mg in H. pylori-positive and -negative volunteers, respectively (p < 0.01).

CONCLUSIONS

Low antral somatostatin content may cause hypergastrinemia in asymptomatic healthy volunteers, and H. pylori may contribute to the pathogenesis of duodenal ulcer, through this mechanism.

Helicobacter pylori infection, serum gastrin, and gastric acid secretion in teen-age subjects with duodenal ulcer, gastritis, or normal mucosa

BACKGROUND

Many studies have confirmed the close association of Helicobacter pylori with duodenal ulcer (DU) in adults. However, in the subtype of DU known as 'childhood' or 'early onset DU' genetic factors seem to play a prominent role in the pathogenesis. The aim of this study was to investigate the prevalence of H. pylori in teen-age subjects with DU, gastritis, and normal mucosa and to examine the relationship of H. pylori to serum gastrin levels and gastric acid secretion.

METHODS

Sixty-one teen-age subjects (24 with DU, 14 with gastritis, and 23 normal subjects) were investigated for the presence of H. pylori, antral histology, gastrin levels, basal acid output (BAO), and maximal acid output (MAO).

RESULTS

All 24 patients with DU and 8 of 14 with gastritis were infected with H. pylori; none of the normal subjects were infected. Mean gastritis scores and fasting serum gastrin levels were significantly higher in patients with DU or H. pylori-positive gastritis than in subjects with H. pylori-negative gastritis or normal mucosa (p < 0.05). The difference in serum gastrin levels was also significant when patients with DU were compared with those with H. pylori-positive gastritis (p < 0.05). BAO and MAO were significantly higher in patients with DU than in subjects with H. pylori-positive gastritis or normal mucosa (p < 0.05), but there was no difference between subjects with H. pylori-positive gastritis and those with normal mucosa.

CONCLUSION

H. pylori infection is associated closely with teen-age DU and gastritis and with hypergastrinemia but does not affect BAO and MAO in most infected teen-age subjects.

Correlation between serum pepsinogen concentration and gastric acidity measured by 24 h pH monitoring

The relationship between the intragastric pH measured by 24 h pH monitoring system and the serum pepsinogen I/II ratio was studied in 68 cases. When pepsinogen I/II ratio was compared with pH 3.0 holding time (the percentage time during which the gastric pH is above 3.0), there was a negative correlation between these two parameters (correlation coefficient r = -0.62, P < 0.001). Furthermore, there was also a strong negative correlation between the early morning (from 03.00 to 06.00 h) gastric pH and pepsinogen I/II ratio (r = -0.76, P < 0.001). Accordingly, by simply measuring serum pepsinogen I and II, it may be possible to infer gastric acidity and to obtain the information concerning the early morning intragastric pH.

The effect of tripotassium dicitrato bismuthate on the rat stomach

BACKGROUND

Bismuth has been used as symptomatic treatment of dyspepsia for many years. It promotes healing of peptic ulcers and reduces their recurrence. The beneficial effect of bismuth on duodenal ulcer disease is thought to be due to an effect on Helicobacter pylori, although it has a rather weak bactericidal effect on H. pylori in vitro. Eradication of H. pylori in duodenal ulcer patients by a combination of bismuth, tetracycline and metronidazole has been reported to increase the density of somatostatin-producing D cells in the antrum. A reduced D cell density in the antral mucosa of duodenal ulcer patients could explain their exaggerated gastrin release.

AIMS/METHODS

To test the possibility that bismuth could affect the neuroendocrine cells independently of the presence of H. pylori or not, we gave rats a diluted tripotassium dicitrato bismuthate solution by gastric gavage for 14 days.

RESULTS

Tripotassium dicitrato bismuthate treatment did not affect maximal pentagastrin-stimulated acid secretion or histamine release in isolated rat stomachs or the density of argyrophil cells in the oxyntic and antral mucosa. However, it significantly reduced the duodenal concentration of gastrin and calcitonin gene-related peptide, and the density of G cells in the antrum and duodenum.

CONCLUSION

The effect of tripotassium dicitrato bismuthate on the G cell may be of significance for its beneficial effect on duodenal ulcer disease.

How does Helicobacter pylori cause duodenal ulcer disease: the bug, the host, or both?

Helicobacter pylori infection is the most common cause of duodenal ulcer disease, yet duodenal ulcer is an uncommon outcome of H. pylori infection. We reviewed the possible explanations such as differences in the host or in the strain of H. pylori. Host factors reviewed included genetic susceptibility to H. pylori infection and excess gastric acid secretion. The role of potential H. pylori virulence factors not present in all strains such as the cagA gene and the results of other molecular methods to identify disease-specific differences among isolates was also reviewed. Although cure of H. pylori infection resolves gastrin releasing peptide stimulated acid secretion there was no change in parietal cell mass. Twin studies have shown genetic differences in H. pylori susceptibility. There was no difference in the prevalence of the cagA gene between H. pylori infected asymptomatic volunteers and duodenal ulcer patients (P = 1.0). DNA-DNA hybridization of whole genomic DNA in solution and cluster analysis of rep-PCR genomic DNA fingerprints suggest that isolates from patients with duodenal ulcer disease are different from those obtained from individuals with asymptomatic gastritis. Cluster analysis of the rep-PCR DNA fingerprints revealed two major groups of the strains; one set consisted of strains from patients with duodenal ulcer disease and the second cluster consisted largely of strains from individuals with asymptomatic gastritis. Recent molecular studies suggest that disease-specific cell lineages or strains may exist among H. pylori isolates leading to the various outcomes observed in patients with H. pylori infection.

Determinants of symptoms suggestive of gastroesophageal reflux disease in the elderly

The study material consisted of 487 subjects from a stratified random sample of the non-institutionalized population of Turku aged 65 years or more (n = 24,937). The study was based on a population study on health status and sleeping habits of the elderly. Information on health status and medications was obtained by means of interviews and from the national health insurance records of the subjects. A postal questionnaire inquired about symptoms suggestive of gastroesophageal reflux disease (GERD). In univariate analyses, perceived poor health, insomnia, disability, depression, previous peptic ulcer, cholelithiasis, and bronchial asthma were associated with daily symptoms suggestive of GERD. Moreover, the symptoms were associated with the use of beta-blocking agents, benzodiazepines, and neuroleptic agents. In multivariate analyses, previous peptic ulcer, perceived poor health, insomnia, and use of benzodiazepines were independently associated with symptoms suggestive of GERD. In conclusion, the determinants of symptoms suggestive of GERD in the elderly differ from those reported in young and middle-aged subjects.

A study of the pathogenesis of Helicobacter pylori negative chronic duodenal ulceration

In the past five years 12 patients have been identified presenting with chronic duodenal ulcer (DU) disease and with no evidence of current or recent Helicobacter pylori (H pylori) infection. Four of them were taking regular non-steroidal anti inflammatory agents, one was subsequently found to have Crohn's disease of the duodenum, and one to have the Zollinger-Ellison syndrome. The remaining six patients with idiopathic DU disease were remarkable for their absence of the A1 blood antigen gene. Detailed studies of gastric function were performed in these six patients and compared with H pylori positive patients with DU and with healthy volunteers. The median integrated gastrin response in the patients with idiopathic DU (2810 (range 750-8750) ng/l min) was similar to that of the H pylori positive patients with DU (3355 (550-8725)) and higher than that of the H pylori negative healthy volunteers (560 (225-1125)). The median peak acid output in the patients with idiopathic DU (37 mmol/h, range 17-52) was similar to that of the H pylori positive patients with DU (40 (15-57)) and higher than that of the non-ulcer controls (22 (16-29)). The median percentage of a liquid meal retained in the stomach at 60 minutes was less in the patients with idiopathic DU (23 (15-33)) than in H pylori negative healthy volunteers (34 (30-53) p < 0.01). The median percentage of a solid meal retained at 60 minutes was less in the patients with idiopathic DU (54 (9-83)) than in either H pylori negative healthy volunteers (87 (49-95) p<0.01) or H pylori positive patients with DU (79 (51-100) p<0.01). In conclusion, three abnormalities of gastric function are prevalent in patients with H pylori negative idiopathic DU disease - hypergastrinaemia, increased acid secretion, and the one feature distinguishing them from H pylori positive patients with DU - rapid gastric emptying of both liquids and solids. Each of these abnormalities will increase the exposure of the duodenal mucosa to acid and thus explain its ulceration. The absence of the blood group A1 antigen gene is consistent with a genetic basis for the disturbed gastric function linked to the ABO blood group antigen genes.

The role of Helicobacter pylori in peptic ulcer disease

The linking of relapse of duodenal as well as gastric ulcers with Helicobacter pylori (H. pylori) has been a considerable advance in managing patients with peptic ulcer disease. However, pathogenetic role of H. pylori in peptic ulcer still remains unclear. The aim of this study was to assess the relationship between H. pylori infection and inflammatory cell infiltration in gastric mucosa in peptic ulcer disease. Sixty-four patients with endoscopically proven gastric ulcer and 26 patients with duodenal ulcer were evaluated by prospective study. Biopsy specimens were taken from the ulcer margin, corpus and antrum. Eradication of H. pylori was attempted by concomitant administration of amoxycillin 500 mg, metronidazole 250 mg and bismuth subnitrate 1 g twice daily for 2 weeks. H. pylori positive rates in clinical stages of gastric and duodenal ulcer showed almost the same values of more than 90%. The prevalence of H. pylori at the antrum and corpus was almost the same as that between gastric and duodenal ulcer patients, whereas a dramatic difference in the positive rates at the ulcer margin was observed between gastric and duodenal ulcer patients (83.9% and 35.0%, respectively). The prevalence of polymorphonuclear (PMN) cell infiltration at the ulcer margin was still high even at the scarring stage of gastric and duodenal ulcer with positive H. pylori, whereas a dramatic decrease of PMN cell infiltration was observed at the ulcer margin after successful eradication of H. pylori. These results suggest that H. pylori may play an important role in the pathogenesis of gastric and duodenal ulcer by inducing inflammatory cells such as PMN cells in gastric mocosa.

Antral Helicobacter pylori infection, hypergastrinemia and peptic ulcers: effect of eradicating the organism

BACKGROUND

A randomized prospective study on the response of fasting serum gastrin concentrations in peptic ulcer patients was performed in order to test the hypothesis that H. pylori infection in the gastric antrum increases gastrin release, and to examine whether the high fasting serum gastrin concentrations respond to treatment that eradicates H. pylori.

METHODS

One hundred and twenty-seven patients with gastric or duodenal ulcer were included in this study. Patients were divided into three groups on the basis of antral H. pylori status and therapeutic modalities. The first group, 58 patients infected by H. pylori, was treated with metronidazole and tripotassium dicitrato bismuthate combined with ranitidine and mylanta. The second group, 40 patients also infected by H. Pylori, was treated with ranitidine and mylanta. The third group, 29 patients, free of H. pylori infection, was designed to evaluate the influence of H2-receptor antagonist on the change of gastrin. When ulcers were completely healed, changes of gastrin concentrations and H. pylori status were re-examined.

RESULTS

H. pylori was eradicated in all patients who have received antibacterial therapy in 4 weeks, and serum gastrin concentrations were significantly decreased after eradication of the organism both in gastric and in duodenal ulcer diseases. (Gastric ulcer: 129.3 +/- 47.0 pg/ml before and 63.7 +/- 21.6 pg/ml after treatment. Duodenal ulcer: 108.3 +/- 35.0 pg/ml and 66.5 +/- 21.9 pg/ml, respectively. Total: 112.7 +/- 38.2 pg/ml vs 66.0 +/- 21.6 pg/ml) (p < 0.01). In contrast, H. pylori-positive patients who have not received antibacterial therapy were still infected at the completion of the study, and serum gastrin concentrations increased even though the difference was not significant. (Gastric ulcer: 118.4 +/- 51.2 pg/ml vs 124.0 +/- 56.5 pg/ml. Duodenal ulcer: 85.4 +/- 35.1 pg/ml vs 104.6 +/- 43.5. Total: 99.5 +/- 45.3 vs 112.9 +/- 48.7 pg/ml.) (p > 0.05). None of the patients who were initially H. pylori-negative has been reinfected during the period of the study, and their serum gastrin concentrations were not changed. (Gastric ulcer: 69.8 +/- 38.0 pg/ml. Total: 63.2 +/- 31.1 pg/ml. Duodenal ulcer: 55.1 +/- 17.6 pg/ml vs 55.8 +/- 13.8 pg/ml. Total: 63.2 +/- 31.1 pg/ml vs 63.4 +/- 30.0 pg/ml). Four- to six-week therapy of H2-receptor antagonist and antacid had no influence on serum gastrin concentrations.

CONCLUSIONS

On the basis of the above results, we confirmed that the chronic infection of H. pylori of gastric antrum in peptic ulcer patients causes increased release of serum gastrin, and eradication of the organism results in a significant fall in serum gastrin concentrations.

Pepsinogens in health and disease

Pepsinogens, precursors of pepsins (potent and abundant digestive enzymes that are the primary products of the gastric chief cells), are members of the family of aspartic proteases. Because of the heterogeneity of pepsinogens, several classifications have appeared in the literature. I describe the recommended classification and nomenclature of the aspartic proteases and discuss their genetics, biochemistry (structure, activation of zymogens, mechanism of proteolytic activity and inhibitors), and physiology. The focus will be on the zymogens of pepsin, the so-called pepsinogens. The measurement of these enzymes in serum is a reliable noninvasive biochemical method for evaluating peptic secretion and obtaining information on the gastric mucosal status. A detailed review of the methods for the measurement of pepsinogens in serum, urine, and gastric mucosa is also provided. Data on pepsinogen levels in healthy subjects are discussed with respect to sex, age, smoking habit, and the presence of a circadian rhythm. The value of pepsinogen measurements in peptic ulcer to determine ulcer outcome and recurrence, in gastric cancer, and in Helicobacter pylori infection is reviewed. Finally, the effects of drugs on peptic secretion are discussed. In light of these data, the measurement of aspartic proteases, and in particular that of pepsinogen A and C, may be regarded as an effective biochemical approach to the evaluation and monitoring of patients with upper gastrointestinal diseases.

Role of ammonia in the pathogenesis of the gastritis, hypergastrinaemia, and hyperpepsinogenaemia I caused by Helicobacter pylori infection

Studies were performed in patients with and without renal failure to investigate the role of bacterial ammonia production in the pathogenesis of the mucosal abnormalities caused by Helicobacter pylori. The high rate of H pylori ammonia production in uraemic patients should accentuate any ammonia induced effects. The median (range) gastric juice ammonium concentration in the H pylori positive patients with renal failure was 19 mmol/l (II-43) compared with 5 mmol/l (1-11) in the H pylori positive patients without renal failure (p < 0.005). In the H pylori negative patients the values were 3 mmol/l (0.5-11) and 0.7 mmol/l (0.1-1.4) respectively in the patients with and without renal failure (p < 0.01). Despite the much higher ammonia production in the H pylori positive uraemic patients, the nature and severity of their gastritis was the same as that in the H pylori positive non-uraemic patients. The median (range) fasting serum gastrin concentration was raised in the uraemic patients compared with the non-uraemic patients but was similar in the uraemic patients with (95 pmol/l (52-333)) or without (114 pmol/l (47-533)) H pylori infection. The median (range) serum pepsinogen I concentration was also high in the uraemic compared with the non-uraemic patients and was significantly higher in uraemic patients with H pylori (352 ng/ml, range 280-653) than in those without H pylori infection (165 ng/ml, range 86-337) (p < 0.01). These findings indicate that the gastritis and hypergastrinaemia associated with H pylori infection are not the result of mucosal damage induced by the organism's ammonia production.

Helicobacter pylori: past, present, and future

Helicobacter pylori has now been recognized as one of the most common chronic human infections. It has been accepted as an important aetiologic agent in non-immune chronic gastritis and plays a key role in the aetiology of duodenal ulcer. It may also be involved in the pathogenesis of gastric cancer.