H. pylori infection and visceral hypersensitivity in patients with irritable bowel syndrome

BACKGROUND/AIM

Irritable bowel syndrome (IBS) is characterized by abdominal pain and changes in stool habits. Visceral hypersensitivity (VH) is a key factor in the pathophysiology of IBS. The role of Helicobacter pylori infection in the induction of VH in the upper gastrointestinal tract is controversially discussed. The aim of this study is to evaluate the value of rectal barostat in eliciting abdominal symptoms in patients with IBS in relation to H. pylori infection.

PATIENTS AND METHODS

31 patients (19 female, 12 male, mean age 45.6 +/- 10 years) with normal colonoscopy and clinical signs of IBS were examined by rectal barostat (pressure-controlled balloon distension in the rectum). Induction of typical abdominal discomfort (far from the balloon) defined the examination positive. Level of nonpainful perception (L1), feeling of defecation (L2), and pain or stool urgency (L3) were registered in comparison with a healthy control group (CG; n = 15, 9 female, 6 male). The H. pylori status was defined by (13)C-urea breath test (n = 46).

RESULTS

Typical abdominal discomfort was induced in 9 patients (pain group, PG) by pressure-controlled rectal distension (H. pylori status: 8 positive, 1 negative). Patients not presenting with abdominal pain to rectal distension (nonpain group, NPG) were all H. pylori negative (p < 0.001). L3 as an indicator of VH was reached at a lower pressure threshold in PG than in NPG or CG (p < 0.05). The perception was not different between NPG and CG (p > 0.05).

CONCLUSIONS

The induction of typical abdominal discomfort in patients with IBS by the use of rectal barostat occurred predominantly in H. pylori infected patients and suggests that H. pylori infection may be involved in triggering VH in patients with IBS. Further studies in larger patient groups and after H. pylori eradication therapy are needed to confirm and extend this observation.

Validity of a Helicobacter pylori stool antigen assay for the assessment of H. pylori status following eradication therapy

BACKGROUND

A Helicobacter pylori stool antigen (HpSA) test has been proposed as a valid alternative to the 13C-urea breath test (13C-UBT) for the non-invasive detection of H. pylori infection in primary diagnosis. Published reports show conflicting results with regard to the test's diagnostic accuracy after eradication therapy. The aim of the present study was to assess the diagnostic value of the HpSA test and to determine the optimal discriminating cut-off value in patients following H. pylori eradication therapy.

METHOD

Stool samples were collected and the 13C-UBT was performed in 113 patients 4-6 weeks after eradication therapy. A validated test protocol for the 13C-UBT was used. Stool specimens were analysed with the Premier Platinum HpSA enzyme immunoassay (EIA). A receiver operator characteristics (ROC) analysis was performed to define the optimal cut-off value on the basis of the results of the 13C-UBT.

RESULTS

The results of the 13C-UBT showed that H. pylori eradication was successful in 83/113 (73%) patients. According to the manufacturer, the cut-off value for the HpSA test is 0.14 optical density, but this does not appear to be valid after eradication therapy (sensitivity 76.7%, specificity 98.8%). On the basis of ROC analysis, the optimal cut-off value after therapy was determined to be 0.11 optical density, giving a sensitivity of 93.3% and a specificity of 93.9%.

CONCLUSION

The HpSA test is a valid test for the assessment of H. pylori status after eradication therapy, provided an adjusted cut-off value is applied.

[Reflux esophagitis--a community-wide increase in incidence]

Gastroesophageal reflux disease (GERD) is a common disease increasing in incidence and prevalence in the industrialised countries. It is a chronic disease with a large spectrum of clinical manifestations. The leading symptom is heartburn, however the disease may also present with extraesophageal symptoms or stay asymptomatic. Motility disorders of the upper GI tract with the key feature of impaired LES are the cause for pathologic gastroesophageal reflux in the terminal esophagus. The relationship of H. pylori infection with GERD is part of the current discussion. The Savary Miller classification for grading of refluxesophagitis is now proposed for substitution by the Los Angeles classification for the assessment of erosive lesions. Besides complications such as bleeding or strictures the main risk is the development of Barrett esophagus and adenocarcinoma. Proton pump inhibitors are the therapy of choice for healing as well as in longterm therapy and prophylaxis. New endoscopic interventional therapies for treatment of GERD and related diseases should be used only in controlled studies.

Comparison of two tubeless function tests in the assessment of mild-to-moderate exocrine pancreatic insufficiency

BACKGROUND

Faecal elastase 1 (FE1) and the pancreolauryl test (PLT) are widely used for the non-invasive diagnosis of exocrine pancreatic insufficiency (EPI). Whether one of these two tests is superior for the detection of mild-to-moderate EPI is the subject of controversy. The aim of this study was to compare the diagnostic performance of the PLT and FE1 for the detection of EPI in patients with chronic pancreatitis.

METHODS

Forty consecutive patients (27 males, 13 females, 23-72 years) with chronic pancreatitis based on imaging procedures (computed tomography, endoscopic retrograde pancreatography and endoscopic ultrasound) were admitted to the study. A secretin-caerulein test (SCT) was performed after an overnight fast by giving secretin (1 U/kg/h) and caerulein (100 ng/kg/h) intravenously over 90 min. Duodenal contents were aspirated at 15 min intervals and analysed for pH, bicarbonate, amylase, lipase and elastase. EPI was graded on the basis of the results of the SCT as absent, mild, moderate or severe. A serum PLT was performed in accordance with a modified protocol previously described. A commercial ELISA was used for determination of FE1. The cut-off values were > or = 4.5 mg/l for PLT and > or = 200 microg/g for FE1. and 13 severe) on the basis of the results of the SCT. The sensitivity of the PLT for diagnosing EPI of all degrees of severity was 82% (27/33), compared with 50% for FE1 (16/ 33). In patients with severe EPI, the PLT was abnormal in 100% (13/13) and FE1 was abnormal in 85% (11/13) of the cases. The sensitivity decreases for both tests in the group of mild/moderate EPI (PLT 70% (14/20), FE1 35% (7/20)). In all seven patients with normal exocrine pancreatic function, both PLT and FE1 were also normal.

CONCLUSIONS

The PLT is more sensitive than FE1 for the diagnosis of mild-to-moderate EPI, and is therefore more appropriate for completing the staging of chronic pancreatitis.

Helicobacter pylori infection and gastro-oesophageal reflux disease: coincidence or association?

Concerning the relationship between Helicobacter pylori infection and gastro-oesophageal reflux disease (GORD), the debate is ongoing whether the infection confers protection, is harmful or whether both entities are independent. Epidemiological evidence is given for an increased prevalence of GORD and a decreased prevalence of H. pylori infection in the western world. The assumpton derived from it is that H. pylori protects from GORD. Pathophysiological aspects need to consider the type and expression of gastritis which is associated with varying changes of gastric function. Depending on the type of gastritis, acid secretion may either increase or decrease and thereby impact on acid exposure of the oesophagus. Other changes related to the role of H. pylori in pathophysiology of GORD are still hypothetical. Clinical data are controversial whether or not GORD increases after H. pylori eradication. Prospective studies including characterization of strains and gastric physiology will clarify this issue. An accelerated induction of gastric mucosal atrophy in patients on long-term proton pump inhibitors is reported in most available studies. An increase of inflammatory activity in fundic and corpus mucosa is a consistent phenomenon. Therefore, in the authors' opinion, eradication appears advisable.

[Optimizing antrum planimetry for ultrasound determination of gastric emptying using emptying function reference lines]

Previous studies have shown high inter- and intraindividual variation coefficients (Vkinter; Vkintra) of the gastric emptying time t(end) determined by sonographical antrum planimetry.

PURPOSE

Are there new parameters reflecting the functional process of gastric emptying?

METHOD

Gastric emptying of 300 ml water was studied in 20 healthy volunteers by sonographical antrum planimetry. 10 volunteers were examined a second time on another day.

RESULTS

High variation coefficients Vkinter (42%) and Vkintra (31%) could be demonstrated. Moreover, a correlation of r = +0.922 between tend and the maximal percentual increase of the antral area was evident. This relation is introduced as the functional-emptying-line (FEL).

CONCLUSION

Using the functional aspects of FEL, gastric emptying can be studied sonographically under functional aspects.