Effects of anti-Helicobacter pylori treatment and probiotic supplementation on intestinal microbiota.

The aims of this study were (i) to evaluate the effect of recommended antimicrobial treatment of Helicobacter pylori infection, consisting of clarithromycin, amoxicillin and lansoprazole, on intestinal microbiota and (ii) to determine the ability of a probiotic combination containing Lactobacillus rhamnosus GG, L. rhamnosus LC705, Propionibacterium freudenreichii ssp. shermanii JS and Bifidobacterium breve Bb99 to prevent treatment-induced alterations in the intestinal microbiota. Faecal samples were obtained from 39 H. pylori-infected patients randomised into two treatment groups. In addition, 19 H. pylori-negative volunteers were included in the study as a control group. Samples were collected before, during and after treatment and microbiota were analysed by fluorescence in situ hybridisation and culture. The quantities of the predominant bacterial groups were altered significantly in both groups and disturbances were seen even 9 weeks after treatment was complete. Probiotics slightly counteracted the effects of anti-H. pylori treatment, seen as significantly less alterations in the total numbers of aerobes and lactobacilli/enterococci. At baseline, the composition of the microbiota between H. pylori-positive versus H. pylori-negative control individuals differed with regard to clostridia and the total number of anaerobes. The recommended treatment for H. pylori infection induces long-term disturbances in the intestinal microbiota. The probiotic combination appeared to result in only minor changes in the microbiota.

Probiotic supplementation improves tolerance to Helicobacter pylori eradication therapy--a placebo-controlled, double-blind randomized pilot study.

BACKGROUND: H. pylori is the major cause of chronic gastritis, and a risk factor for peptic ulcer and gastric cancer. AIM: To investigate the effect of probiotic supplementation on the tolerance and efficacy of H. pylori eradication treatment in a randomized, double-blind, placebo-controlled trial. METHODS: A total of 338 volunteers were screened for H. pylori infection. The eligibility criteria were met by 47 subjects whose H. pylori infection was verified at the outset and re-evaluated after the treatment by the 13C-urea breath test and by enzyme immunoassay serology. The subjects were randomized to receive probiotic therapy (Lactobacillus rhamnosus GG, L. rhamnosusLC705, Bifidobacterium breve Bb99 and Propionibacterium freudenreichii ssp. shermanii JS) or a placebo during H. pylori eradication and for 3 weeks following the treatment, and recorded their daily symptoms in a standardized diary. RESULTS: When the frequencies of new or aggravated symptoms were evaluated, no significant differences were found between the two groups for individual symptoms. However, the probiotic group showed less treatment-related symptoms as measured by the total symptom score change (P = 0.038) throughout the H. pylori eradication therapy in contrast to the placebo group. The H. pylori eradication rate was non-significantly higher in the group receiving probiotic therapy (91% vs. 79%, P = 0.42). In this group the recovery of probiotic bacteria in the faeces increased significantly (P < 0.001). CONCLUSIONS: In this pilot study, probiotic supplementation did not diminish significantly the frequency of new or aggravated symptoms during H. pylori eradication. However, our data suggest an improved tolerance to the eradication treatment when total symptom severity was taken into account. Furthermore, the results show that probiotic bacteria are able to survive in the gastrointestinal tract despite the intensive antimicrobial therapy.

Atrophic gastritis and Helicobacter pylori infection in outpatients referred for gastroscopy.

BACKGROUND: Atrophic gastritis has been shown to be one of the long term sequelae of Helicobacter pylori infection. AIMS: To determine the prevalence of atrophic gastritis in outpatients, to study the accuracy of serological methods for revealing atrophy, and to define the association of H pylori infection with atrophic gastritis in these patients. PATIENTS/METHODS: A total of 207 consecutive outpatients referred for gastroscopy were included. Biopsy specimens from the antrum and corpus were assessed histologically according to the Sydney system. Serum samples were studied for H pylori IgG and IgA antibodies by enzyme immunoassay, CagA antibodies by immunoblot, pepsinogen I by an immunoenzymometric assay, gastrin by radioimmunoassay, and parietal cell antibodies by indirect immunofluorescence. RESULTS: Histological examination revealed atrophic gastritis in 52 (25%) of 207 patients. H pylori and CagA antibodies were strongly associated with atrophic antral gastritis but poorly associated with atrophic corpus gastritis. Low serum pepsinogen I was the most sensitive and specific indicator of moderate and severe atrophic corpus gastritis. All six patients with moderate atrophic corpus gastritis had H pylori infection but eight of 10 patients with severe atrophic corpus had increased parietal cell antibodies and nine had no signs of H pylori infection. CONCLUSIONS: Atrophic antral gastritis was strongly associated with CagA positive H pylori infection. Severe atrophic corpus gastritis was not determined by H pylori tests but low serum pepsinogen I, high gastrin, and parietal cell antibodies may be valuable in detecting these changes.

Evaluation of Pyloriset Screen, a rapid whole-blood diagnostic test for Helicobacter pylori infection.

Helicobacter pylori infection can be detected by several invasive tests based on gastroscopy and by noninvasive methods such as serologic assays. Noninvasive tests can be used not only in addition to invasive tests but also by themselves to screen for H. pylori infection in patients who are not in urgent need of endoscopy. Lately, rapid qualitative serologic tests have been developed. In the present study, the accuracy of a novel rapid whole-blood test, Pyloriset Screen, detecting immunoglobulin G (IgG) and IgA antibodies against H. pylori was evaluated. A total of 207 consecutive adult outpatients referred for upper endoscopy were enrolled. Gastric biopsy specimens were taken from the antrum and corpus for histologic examination and rapid urease testing. Cultures were available for 113 patients. Serum samples collected from all patients were tested for H. pylori antibodies by two enzyme immunoassays (EIAs) (Pyloriset EIA and an in-house EIA), a rapid latex agglutination test (Pyloriset Dry), and Pyloriset Screen. Patients were considered H. pylori positive if helicobacters were seen on histologic examination (77 patients) or, if in combination with histologically verified (although helicobacter-negative) gastritis, their IgG antibody titers were elevated in the two EIAs (five patients). The Pyloriset Screen test had a sensitivity of 95%, a specificity of 94%, a positive predictive value of 91%, and a negative predictive value of 97%. Among 63 patients under the age of 45 years, the Pyloriset Screen test did not miss a single H. pylori diagnosis, and only 1 patient had a false-positive result. Pyloriset Screen could be used reliably to screen for H. pylori infection.

Innervation of the human gastric wall.

The intrinsic innervation of the human gastric wall was studied by means of (1) demonstration of the acetylcholinesterase activity, (2) fluorescence microscopy, and (3) electron microscopy. The cholinergic innervation was rich: in the mucosa, a dense three dimensional network consisting of single delicate varicose acetylcholinesterase-positive axons and small nerve fascicles was observed in close relation to the gastric glands. In the submucosa, large nerve trunks and densely woven plexuses mainly consisting of single varicose axons (obviously perivascular plexuses)) were seen. In the muscularis external, a small-meshed net consisting of single varicose axons and nerve fascicles was observed. The ganglia of the myenteric plexus were small and scattered irregularly between and within the muscle layers. Most of the nerve cells exhibited moderate to intense acetylcholinesterase activity. In the serosa, only a few nerves were observed. By fluorescence microscopy, an abundance of brightly yellow fluorescing irregularly fusiform enterochromaffin cells was observed in the epithelial lining of the antral glands. The parietal cells of the fundic glands exhibited a granular, yellow to orange autofluorescence. Fluorescing axons were seen in intimate relation to some enterochromaffin cells, whereas most enterochromaffin cells and parietal cells did not receive any direct functional adrenergic innervation. In the other tissue layers, only a few fluorescing nerves were seen. The main ultrastructural characteristics of the intrinsic innervation of the mucosa were: (1) 'Innervation fasciculée'; (2) the axons were unmyelinated; (3) two main types of nerve terminals were identified according to their vesicle population(s): (a) nerve terminals containing only clear vesicles, (b) nerve terminals containing clear vesicles and large dense-cored vesicles. Most of the axons and nerve terminals within the nerve fascicles were acetylcholinesterase-positive. The nerve terminals were separated from the gastric glands (and the parietal cells, chief cells and endocrine cells of their epithelial lining) by a considerable gap so that it seems unlikely that the gastric glands, parietal cells, chief cells and endocrine cells receive a direct innervation in the sense of synaptic neurotransmission; the transmitter substance must diffuse across a wide gap. In contrast, the endocrine cells were in close contact with the parietal cells and chief cells, and occasional membrane specialization (desmosomes) reinforce the assumption that (also) direct local humoral interaction may be possible. In addition, a large number of mast cells was observed in the lamina propria, many lying as close to glandular cells (parietal cells, chief cells and endocrine cells) as were the nearest nerve terminals.

Atrial acetylcholinesterase activity in various heart diseases of man.

Distribution and activity of the acetylcholinesterase enzyme in the human atrial myocardium was studied histochemically in a clinical series of patients subjected to cardiac surgery for (1) uncomplicated atrial septal defect (ASD), (2) ischaemic heart disease (IHD), (3) mitral and/or aortic valvular disease (VHD) necessitating replacement with a prosthetic valve, without major symptoms or signs of myocardial incompensation, or (4) clinically overt congestive heart failure (CHF) due to VHD prior to cardiac surgery. In all specimens, a rich distribution of acetylcholinesterase-positive single axons and small fascicles, constituting a three-dimensional nerve net, was observed within the myocardial tissue. This nerve net was obviously mainly parenchymatous, i.e. unrelated to the blood vessels. Small groups of acetylcholinesterase-positive small nerve cells were observed in some specimens, with loosely woven fascicles of axons emerging from one pole of the ganglia. No differences in the distribution of the acetylcholinesterase activity or in the pattern of the inbuilt intrinsic nervous apparatus were observed in the various groups of patients. All specimens were completely devoid of non-specific cholinesterase activity. It was concluded that (I) the human atrial myocardium is richly supplied with cholinergic intrinsic (post-ganglionic vagal) axons and (II) the acetylcholinesterase activity is not a major determinant of the parasympathetic abnormalities associated with cardiac diseases, especially with myocardial pump failure.

Cholinergic innervation of the gastric wall of the cat.

The inbuilt intrinsic cholinergic nervous apparatus of the gastric wall of the cat was studied by using two thiocholine methods for mapping the acetylcholinesterase-positive nerves and nerve cells. A rich distribution of acetylcholinesterase-positive nerves was observed in all layers of the gastric wall, except the superficial half of the lamina propria (with the epithelium), which was completely devoid of acetylcholinesterase activity, and the submucosa, in which a scarce distribution of large nerve fascicles and nerve trunks was observed. Acetylcholinesterase-positive ganglia were observed both in the subserous layer and in the myenteric plexus of Auerbach, whereas none were recognized in the submucous plexus of Meissner. This obviously fits well to the results of some electrophysiological experiments which indicate that the submucous plexus of Meissner includes an important intramural pathway from the extrinsic vagus nerves to the antrum region; so the submucous plexus of Meissner seems to be mainly involved in direct rapid conduction of nerve impulses without integrative activities, like a cable. Certain clear differences exist in the pattern of organization of the cholinergic intrinsic nervous apparatus within the different layers of the gastric wall in the fundic and pyloric regions. These differences seem to correspond quite logically to the different types of motor, secretory and neurohumoral activities of these main regions of the stomach. The activity of the non-specific cholinesterases was localized both in the neural elements and the smooth muscle, as well as in some epithelial cells.