Basal and stimulated gastrin and pepsinogen levels after eradication of Helicobacter pylori: a 1-year follow-up study

Non-invasive diagnostic tests for Helicobacter pylori infection

BACKGROUND

Helicobacter pylori (H pylori) infection has been implicated in a number of malignancies and non-malignant conditions including peptic ulcers, non-ulcer dyspepsia, recurrent peptic ulcer bleeding, unexplained iron deficiency anaemia, idiopathic thrombocytopaenia purpura, and colorectal adenomas. The confirmatory diagnosis of H pylori is by endoscopic biopsy, followed by histopathological examination using haemotoxylin and eosin (H & E) stain or special stains such as Giemsa stain and Warthin-Starry stain. Special stains are more accurate than H & E stain. There is significant uncertainty about the diagnostic accuracy of non-invasive tests for diagnosis of H pylori.

OBJECTIVES

To compare the diagnostic accuracy of urea breath test, serology, and stool antigen test, used alone or in combination, for diagnosis of H pylori infection in symptomatic and asymptomatic people, so that eradication therapy for H pylori can be started.

SEARCH METHODS

We searched MEDLINE, Embase, the Science Citation Index and the National Institute for Health Research Health Technology Assessment Database on 4 March 2016. We screened references in the included studies to identify additional studies. We also conducted citation searches of relevant studies, most recently on 4 December 2016. We did not restrict studies by language or publication status, or whether data were collected prospectively or retrospectively.

SELECTION CRITERIA

We included diagnostic accuracy studies that evaluated at least one of the index tests (urea breath test using isotopes such as 13C or 14C, serology and stool antigen test) against the reference standard (histopathological examination using H & E stain, special stains or immunohistochemical stain) in people suspected of having H pylori infection.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the references to identify relevant studies and independently extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We performed meta-analysis by using the hierarchical summary receiver operating characteristic (HSROC) model to estimate and compare SROC curves. Where appropriate, we used bivariate or univariate logistic regression models to estimate summary sensitivities and specificities.

MAIN RESULTS

We included 101 studies involving 11,003 participants, of which 5839 participants (53.1%) had H pylori infection. The prevalence of H pylori infection in the studies ranged from 15.2% to 94.7%, with a median prevalence of 53.7% (interquartile range 42.0% to 66.5%). Most of the studies (57%) included participants with dyspepsia and 53 studies excluded participants who recently had proton pump inhibitors or antibiotics.There was at least an unclear risk of bias or unclear applicability concern for each study.Of the 101 studies, 15 compared the accuracy of two index tests and two studies compared the accuracy of three index tests. Thirty-four studies (4242 participants) evaluated serology; 29 studies (2988 participants) evaluated stool antigen test; 34 studies (3139 participants) evaluated urea breath test-13C; 21 studies (1810 participants) evaluated urea breath test-14C; and two studies (127 participants) evaluated urea breath test but did not report the isotope used. The thresholds used to define test positivity and the staining techniques used for histopathological examination (reference standard) varied between studies. Due to sparse data for each threshold reported, it was not possible to identify the best threshold for each test.Using data from 99 studies in an indirect test comparison, there was statistical evidence of a difference in diagnostic accuracy between urea breath test-13C, urea breath test-14C, serology and stool antigen test (P = 0.024). The diagnostic odds ratios for urea breath test-13C, urea breath test-14C, serology, and stool antigen test were 153 (95% confidence interval (CI) 73.7 to 316), 105 (95% CI 74.0 to 150), 47.4 (95% CI 25.5 to 88.1) and 45.1 (95% CI 24.2 to 84.1). The sensitivity (95% CI) estimated at a fixed specificity of 0.90 (median from studies across the four tests), was 0.94 (95% CI 0.89 to 0.97) for urea breath test-13C, 0.92 (95% CI 0.89 to 0.94) for urea breath test-14C, 0.84 (95% CI 0.74 to 0.91) for serology, and 0.83 (95% CI 0.73 to 0.90) for stool antigen test. This implies that on average, given a specificity of 0.90 and prevalence of 53.7% (median specificity and prevalence in the studies), out of 1000 people tested for H pylori infection, there will be 46 false positives (people without H pylori infection who will be diagnosed as having H pylori infection). In this hypothetical cohort, urea breath test-13C, urea breath test-14C, serology, and stool antigen test will give 30 (95% CI 15 to 58), 42 (95% CI 30 to 58), 86 (95% CI 50 to 140), and 89 (95% CI 52 to 146) false negatives respectively (people with H pylori infection for whom the diagnosis of H pylori will be missed).Direct comparisons were based on few head-to-head studies. The ratios of diagnostic odds ratios (DORs) were 0.68 (95% CI 0.12 to 3.70; P = 0.56) for urea breath test-13C versus serology (seven studies), and 0.88 (95% CI 0.14 to 5.56; P = 0.84) for urea breath test-13C versus stool antigen test (seven studies). The 95% CIs of these estimates overlap with those of the ratios of DORs from the indirect comparison. Data were limited or unavailable for meta-analysis of other direct comparisons.

AUTHORS' CONCLUSIONS

In people without a history of gastrectomy and those who have not recently had antibiotics or proton ,pump inhibitors, urea breath tests had high diagnostic accuracy while serology and stool antigen tests were less accurate for diagnosis of Helicobacter pylori infection.This is based on an indirect test comparison (with potential for bias due to confounding), as evidence from direct comparisons was limited or unavailable. The thresholds used for these tests were highly variable and we were unable to identify specific thresholds that might be useful in clinical practice.We need further comparative studies of high methodological quality to obtain more reliable evidence of relative accuracy between the tests. Such studies should be conducted prospectively in a representative spectrum of participants and clearly reported to ensure low risk of bias. Most importantly, studies should prespecify and clearly report thresholds used, and should avoid inappropriate exclusions.

Helicobacter pylori eradication improves the quality of life regardless of the treatment outcome: A multicenter prospective cohort study

Helicobacter pylori (Hp) eradication is recommended for improving the quality of life (QOL) of patients with epigastric symptoms, especially reflux and dyspepsia. However, no reports have investigated the improvement of QOL after the eradication of Hp irrespective of epigastric symptoms. The aim of this study was to investigate the improvement in the QOL after the eradication of Hp irrespective of epigastric symptoms, and evaluate the factors associated with an improved QOL after the eradication of Hp.This prospective cohort study was performed at 15 referral institutions from September 2013 to December 2014. The patients' QOL and epigastric symptoms were evaluated before and after the eradication of Hp using the 8-item Short-Form Health Survey (SF-8) and the modified Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease, respectively.One hundred sixty-five of 184 Hp-infected patients underwent Hp eradication treatment. The treatment was successful in 82.4% (136/165) of the cases. One hundred sixty of the 165 Hp-infected patients were eligible for inclusion in the QOL analysis. In the indices of QOL on the SF-8, the scores on both the mental component summary (MCS) and the physical component summary (PCS) were found to have significantly improved after the eradication of Hp. However, the epigastric symptoms before the eradication of Hp were not correlated with either the MCS or PCS. A low QOL value before the eradication of Hp was the factor what was most strongly associated with the improvement in the QOL.The eradication of Hp improved the QOL, regardless of the outcome of the treatment, especially in patients who had an impaired QOL before the eradication.

Long-term dynamics of gastric biomarkers after eradication of Helicobacter pylori infection

BACKGROUND

Secretion of pepsinogen I (PgI), pepsinogen II (PgII), fasting gastrin-17 (fG-17) and stimulated gastrin-17 (sG-17) changes after Helicobacter pylori eradication. Few data are available on the long-term dynamics of gastric biomarkers after H. pylori eradication.The aim of this study was to investigate the dynamics of gastric biomarkers in H. pylori-positive patients after eradication over a 3-year period and to compare the levels with initially H. pylori-negative patients.

MATERIALS AND METHODS

Blood samples for the detection of gastric biomarkers were obtained from dyspeptic patients coming for upper gastrointestinal endoscopy. In H. pylori-positive patients, after eradication therapy, three follow-up blood samples were drawn after 12, 24 and 36 months; in H. pylori-negative patients, two samples were taken - at 12 and after 30 months. Median values of biomarkers in follow-up samples were compared with the baseline sample.

RESULTS

The final sample included 110 patients (median age 67 years, M/F ratio 27/83). In patients after H. pylori eradication (n=83) PgI, PgII, fG-17 and sG-17 had decreased significantly during a 36-month period, whereas the PgI/PgII ratio had increased significantly from 5.59 to 11.64.

CONCLUSION

In H. pylori-positive dyspeptic patients, after eradication therapy, a decrease in PgI, PgII, fG-17 and sG-17 was observed after 36 months whereas an increase in the PgI/II ratio suggested an improvement in gastric atrophy. The median levels of gastric biomarkers in patients after H. pylori eradication therapy may become similar to biomarker levels among initially H. pylori-negative individuals.

Decrease of serum level of gastrin in healthy Japanese adults by the change of Helicobacter pylori infection

BACKGROUND AND AIM

In Japan, the prevalence of Helicobacter pylori infection is decreasing and the number of patients who receive eradication therapy is increasing. Although the serum level of gastrin is affected by H. pylori infection, the normal level has been unchanged for more than 20 years. The aim of this study was to study whether the present normal range for the serum gastrin level is appropriate for Japanese at present or in the near future.

METHODS

We studied 810 adults (40-80 years old) who participated in a health survey in 2012. We measured H. pylori stool antigen, titer of serum antibody to H. pylori, and serum level of gastrin. The patient's H. pylori status was defined as positive or negative when the results of both stool antigen and serology were concordant. Subjects who were taking proton-pump inhibitor and had a previous history of gastric surgery were excluded.

RESULTS

Mean serum level of gastrin was 66.2±49.6 pg/mL in 281 H. pylori-negative subjects and 69.7±42.2 pg/mL in 115 patients who had H. pylori eradicated at least 2 years ago. The level of gastrin was 134.4±145.6 pg/mL in 224 patients with H. pylori infection and the level was significantly higher when compared with those in uninfected subjects and eradicated patients (P<0.01).

CONCLUSIONS

Because the situation of H. pylori infection has changed remarkably in Japan, a new appropriate normal range of gastrin should be established using current Japanese populations.

Pepsinogen II can be a potential surrogate marker of morphological changes in corpus before and after H. pylori eradication

Background. The aim of this investigation is to study the relationship between gastric morphology and serum biomarkers before and after Helicobacter pylori eradication. Methods. First-degree relatives of gastric cancer patients underwent gastroscopy before and 2.5 years after H. pylori eradication. The morphological changes in two categories (normal to mild and moderate to severe) were compared with level of pepsinogens I and II before eradication (n = 369), after eradication (n = 115), and in those with persistent infection (n = 250). Results: After eradication, pepsinogen I decreased to 70% and pepsinogen II to 45% of the previous values. Unlike pepsinogen II and pepsinogen I to II ratio that were affected by the severity of inflammation and atrophy in corpus in all groups, pepsinogen I generally did not change. After eradication, subjects with high mononuclear infiltration in corpus had lower pepsinogen I (54 versus 77.1 μ/mL), higher pepsinogen II (9.4 versus 6.9 μ/mL), and lower ratio (7.9 versus 11.6) than those without (P < 0.05). Conclusion. Pepsinogen II is a good marker of corpus morphological changes before and after H. pylori eradication.

The role of serum pepsinogen in the detection of gastric cancer

The incidence of gastric cancer is very high in Japan, Korea, and China. Reducing the morbidity and mortality associated with gastric cancer requires early diagnosis, which can be facilitated by applying gastroscopy more frequently in high-risk groups. A strategy of population screening for gastric cancer is currently being adopted in Korea, Japan, and the Matsu region of Taiwan, but using different screening methods. In addition, the history of pepsinogen (PG) in research as a gastric cancer biomarker has varied, in that the use of serum levels of PGI and PGII and the PGI/PGII ratio as gastric cancer screening tools was introduced in Japan before 1990, but in Korea the first research results were only reported in 2008. This review first evaluates the physiology of PG, followed by the usefulness or limitations of serum PG testing with regard to the detection of gastric cancer. Finally, the factors affecting the efficacy of PG tests as a gastric cancer biomarker (i.e., Helicobacter pylori infection status, gender, histopathologic features, and cancer location and depth) are evaluated. It was found that the strategies used to increase the efficacy of PG tests should be individualized in each country according to the seroprevalence of H. pylori.

Serum gastrin and pepsinogens do not correlate with the different grades of severity of gastro-oesophageal reflux disease: a matched case-control study

BACKGROUND

Gastrin and pepsinogens reflect the functional state of the gastric mucosa.

AIM

To evaluate whether serum gastrin and pepsinogens correlate with the different grades of severity of gastro-oesophageal reflux disease (GERD).

METHODS

In all, 388 patients with heartburn not taking any form of acid suppressive therapy were matched-controlled for age and gender and sub-classified into four groups: group 1 non-erosive reflux disease (NERD); group 2, erosive reflux disease (ERD) Los Angeles (LA) A and B, group 3, ERD LA C and D; group 4 Barrett's oesophagus (BO). Fasting serum was analysed for gastrin 17, pepsinogen I, pepsinogen II und Helicobacter pylori using specific EIA tests (GastroPanel; Biohit, Plc).

STATISTICS

Kruskal-Wallis test and analysis of variance.

RESULTS

There was a significant difference among the four groups with respect for pepsinogen I, but not for pepsinogen II, the pepsinogen I pepsinogen II ratio, H. pylori serology and gastrin levels. Pepsinogen I was the lowest in NERD and the highest in BO (median 91.6, mean +/- standard deviation 106.2 +/- 51.6 vs. median 114.7, mean +/- standard deviation 130.4 +/- 70.6; P = 0.046). Pepsinogen I levels were higher in H. pylori positive subjects. After adjusting for H. pylori status, the differences in pepsinogen I across patient groups were no longer statistically significant (P = 0.298).

CONCLUSIONS

Serum gastrin and pepsinogen I and II do not correlate with the different grades of severity of GERD. The non-invasive GastroPanel is not useful for the differentiation of the various forms of GERD.

Using serum pepsinogens wisely in a clinical practice

Serum pepsinogen (PG) has been used as biomarkers of gastric inflammation and mucosal status, including atrophic change, before the discovery of Helicobacter pylori (H. pylori). Serum pepsinogen I (PG I) and pepsinogen II (PG II) levels are known to increase in the presence of H. pylori-related nonatrophic chronic gastritis. The measurement of serum PG provides much information on the presence of intestinal metaplasia as well as atrophic gastritis. The eradication of H. pylori provokes a significant change in serum PG values: it reduces both PG I and PG II and elevates the PG I to PG II ratio. Recently, the serum PG test method has been the first screening step in Japan, as well as photofluorography. Serum PG tests are used to screen for high risk subjects with atrophic gastritis, rather than as a test for cancer itself. Unlike photofluorography or endoscopy, serum PG screening can identify non-ulcerated differentiated asymptomatic cancer, irrespective of the size and location of the lesion. Most cases detected by the PG method are asymptomatic early gastric cancers and are limited to the mucosa, which are particularly well suited for endoscopic treatment. The PG method can contribute greatly to the patients' quality of life.

Gastrin (G) cells and somatostatin (D) cells in patients with dyspeptic symptoms: Helicobacter pylori associated and non-associated gastritis

BACKGROUND

Gastrin G cells and somatostatin D cells are important regulators of gastric acid secretion and alterations in their relative numbers may play a key role in gastroduodenal disease.

AIM

To investigate the effect of Helicobacter pylori infection on the density of immunoreactive G and D cells in gastric antral and corpus biopsies from patients with dyspeptic complaints.

METHODS

One hundred and twenty two patients with dyspeptic complaints had two antrum and two corpus biopsies taken during upper endoscopy. The severity of inflammation and the density of H pylori were evaluated semiquantitatively. In addition, the density and distribution of neuroendocrine cells, especially G and D cells, were examined using immunohistochemistry. Patients were divided into three groups, those with H pylori positive gastritis, H pylori negative gastritis, and histologically normal gastric mucosa.

RESULTS

The number of immunoreactive G cells was significantly higher and the number of immunoreactive D cells lower in patients with H pylori positive gastritis compared with H pylori negative gastritis or histological normal gastric mucosa. The percentage of G cells as a percentage of mucosal endocrine cells was also raised and that of D cells was decreased.

CONCLUSIONS

Helicobacter pylori infection produces alterations in the number of endocrine cells responsible for regulating acid secretion in relation to intragastric pH and feeding. The alterations correlate best with the severity of inflammation and not with H pylori density.

Indicaciones y consecuencias de la erradicación de Helicobacter pylori en la enfermedad por reflujo gastroesofágico

Several epidemiological data indicate that H. pylori infection prevalence in patients with gastroesophageal reflux disease (GERD) is lower than that reported in respective controls, which would suggest that the organism plays a protective role against this disease. On the other hand, most studies demonstrate that the presence of the infection in patients with GERD does not negatively affect the therapeutic efficacy of proton pump inhibitors (PPIs), and, in case of negatively influencing it, the effects are not clinically relevant and are easily controllable with standard antisecretory treatment. Therefore, the decision to administer H. pylori eradication treatment to a patient should not be influenced by the concomitant presence of GERD. In most cases, H. pylori eradication does not seem to induce GERD development, and it does not seem to worsen GERD when it was already present. Nevertheless, when the gastritis pattern is unknown before the antibiotic administration, the effect of H. pylori eradication on gastric acid secretion and the incidence of GERD is unpredictable. In the exceptional cases in which H. pylori eradication could have negative effects on GERD, its clinical relevance will be limited, and reflux symptoms or endoscopic esophagitis will favourably respond to the standard PPI antisecretory treatment. Therefore, again, when H. pylori eradication is indicated in a particular patient, the concomitant diagnosis of GERD should not change our attitude. Finally, is has recently been recommended to eradicate H. pylori infection in those patients with GERD needing long-term treatment with PPI, as some studies have reported that these drugs induce, in presence of the organism, an atrophic gastritis, with the consequent risk of gastric cancer. However, most of these studies have important methodological defects, and several authors have reported contrary results. In any case, the appearance in the gastric mucosa of clinically relevant lesions, such as intestinal metaplasia, dysplasia or adenocarcinoma, in patients treated with PPI for several years, has not yet been demonstrated, although this could simply be a problem of time. This question seems to be too controversial to be answered with the available data, and we should wait until new studies clarify this topic. In the meantime, as it occurs with any controversial indication, the decision of the doctor facing a patient infected by H. pylori and needing maintenance therapy with PPIs should be assessed on a case by case basis.

Improvement in serum pepsinogens and gastrin in long-term monitoring after eradication of Helicobacter pylori: comparison with H. pylori-negative patients

BACKGROUND

A decrease in pepsinogen and gastrin levels 1-3 months after Helicobacter pylori eradication is well known. However, few data are available on the long-term progression of these decreases beyond 1 year after eradication, and there has been no investigation into whether pepsinogen and gastrin levels return to normal levels as defined by data from H. pylori-negative patients with dyspepsia.

AIM

We studied the effect of H. pylori eradication on pepsinogen and gastrin levels for more than 1 year, and compared levels to those in H. pylori-negative patients with dyspepsia. We also investigated the effect of H. pylori eradication on the course of atrophic corpus gastritis as reflected by histology, and on PGI levels and PG I/II ratio.

METHODS

We enrolled 172 H. pylori-positive patients with dyspepsia who had undergone successful eradication therapy of more than 1 year's duration and 101 non-treated H. pylori-negative patients with dyspepsia. H. pylori status was assessed at entry and at each endoscopy after eradication by culture, histological results, the rapid urease test and the urea breath test. In both groups, patients were evaluated for fasting serum pepsinogen I and II and gastrin using a radioimmunoassay technique, and underwent detailed histological assessment according to the updated Sydney System.

RESULTS

In the H. pylori-negative patients, mean serum pepsinogen I and II, I/II ratio and gastrin levels were 52.6 +/- 20.8 ng/mL, 9.2 +/- 4.2 ng/mL, 6.0 +/- 1.7 and 53.5 +/- 29.2 pg/mL, respectively. In H. pylori-positive patients with long-term eradication, pepsinogen I and II, I/II ratio and gastrin levels were 81.3 +/- 46.6 ng/mL, 25.9 +/- 17.1 ng/mL, 3.4 +/- 1.3 and 131.9 +/- 130.8 pg/mL, respectively, before treatment. At 1-3 months after eradication, serum pepsinogen I and II levels in the H. pylori-positive patients decreased to levels similar to those in the negative patients, whereas pepsinogen I/II ratio and gastrin levels remained lower and higher, respectively, than in the negative patients. Serum pepsinogen I/II ratio and gastrin levels then became similar between the groups at 12-15 months after eradication. In histological findings, inflammation and neutrophil activity decreased by 1-3 months, and atrophy in the corpus and metaplasia in the antrum decreased by 12-15 months.

CONCLUSION

The results suggest that atrophic corpus gastritis and superficial gastritis are reversible, as indicated by both histological and serological findings in a long-term follow-up study.

Somatostatin and D cells in patients with gastritis in the course of Helicobacter pylori eradication: a six-month, follow-up study

BACKGROUND/AIMS

As well as causing chronic gastritis, Helicobacter pylori predisposes patients to peptic ulcer disease and gastric cancer, and induces gastric functional disorders. The aim of our study was to investigate the effects of H. pylori eradication therapy on the morphological and functional recovery of gastric antral and corpus D cells in patients with chronic gastritis during 6 months of follow-up.

PATIENTS AND METHODS

Forty consecutive, dyspeptic patients referred for endoscopy (31 with H. pylori infection and nine controls; mean age 49 years; 17 men, 23 women) entered the study. All patients had histological signs of gastritis but no signs of peptic ulcer or gastric cancer. Antrum (n=8) and corpus (n=6) biopsy specimens were collected for routine histology, radioimmunoassay tissue somatostatin levels, immunohistochemistry and electron microscopy, prior to and 6 months after therapy. Basal plasma somatostatin levels were determined prior to eradication, plus 6 weeks and 6 months after therapy. Eradication therapy consisted of amoxicillin, metronidazole and omeprazole.

RESULTS

Basal somatostatin plasma values in antral and corpus tissue were lower in infected patients than in the H. pylori-negative controls at the beginning of the study. A significant increase occurred after successful eradication therapy, together with an increase in the number of D cells in both regions. Changes in the D-cell ultrastructure in antral and corpus mucosa after eradication therapy suggest an increase in somatostatin synthesis and secretion.

CONCLUSIONS

The structural and functional restoration of D cells following eradication therapy indicates possible recovery of the diseased mucosa.

Effect of smoking on serum pepsinogen I level depends on serological status of Helicobacter pylori

Serum pepsinogen (sPG) levels are used in gastric cancer screening programs. However, modification of sPG levels by smoking habit, according to the status of Helicobacter pylori (H. pylori) infection has been little investigated. This study investigated the effects of smoking on serum levels of pepsinogen I (PG I), pepsinogen II (PG II), and gastrin by IgG titer of antibody against H. pylori (Hp-IgG titer) using the data from 356 current-smokers and 262 non-smokers (133 never-smokers and 129 ex-smokers) in a cross-sectional study of 618 men aged 40 to 49 years. PG I, PG II, PG I / PG II ratio and gastrin were significantly associated with Hp-IgG titer in never-smokers [Spearman's correlation coefficient (95% confidence interval): 0.23 (0.07, 0.39), 0.52 (0.41, 0.63), -0.40 (-0.54,-0.27), and 0.25 (0.10, 0.41), respectively]. However, the correlation coefficients of PG I and PG II decreased in current-smokers, 0.02 (-0.1, 0.13) and 0.32 (0.22, 0.42), respectively. In H. pylori seronegative and low titer cases, the mean PG I level was significantly (P < 0.01) higher in current-smokers, compared with non-smokers. However, in high titer cases, the mean PG I level was lower in current-smokers. Mean PG II and gastrin levels, and PG I / PG II ratio did not differ according to smoking habits by Hp-IgG titer. The gastrin level was significantly correlated with PG II, but not PG I. These data indicate that current smoking influences the serum PG I level depending on Hp-IgG titer and the associations between sPGs and Hp-IgG titer. Gastrin is not involved in the modification of PG I levels by smoking.

[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.

Value of quantitative serology for confirmation of Helicobacter pylori eradication: an 18-month follow-up study

In this study several therapies were administered to 124 H. pylori-positive patients and IgG antibody titers were measured by ELISA at months 0, 2, 3, 6, 12, and 18 months. Serum titers of IgG antibody progressively decreased after H. pylori eradication; at 3 months, the area under the receiver operating characteristic curve for the decrease of IgG antibody titers for confirming H. pylori eradication was 0.99, with 100% sensitivity and 99% specificity (when the cutoff point was set at 3 U/mL). We conclude that a decrease in serum titers of IgG antibody to H. pylori relatively early after completion of therapy (1 month after ranitidine or bismuth therapy is completed and 2.5 months after antibiotic therapy is completed) can be used as a noninvasive, simple, and inexpensive method to confirm H. pylori eradication.