Identification of Helicobacter pylori DNA in the mouths and stomachs of patients with gastritis using PCR.

AIMS: To determine the prevalence of Helicobacter pylori colonisation in the mouths of patients with H pylori gastritis. METHODS: A nested polymerase chain reaction test for the 16S ribosomal RNA gene of H pylori was used on saliva, dental plaque, gastric juice and gastric biopsy specimens from patients attending a dyspepsia clinic. RESULTS: Thirteen patients had histologically confirmed Helicobacter associated gastritis. Twelve of these had positive gastric aspirates by PCR. Five had at least one positive oral specimen. Eight patients with normal gastric biopsy specimens had no PCR positive oral specimens or gastric aspirates. All, however, had PCR positive gastric biopsy specimens. In an attempt to determine the origin of these positive results in normal patients, it was shown that biopsy forceps could contaminate specimens with DNA from previous patients. CONCLUSION: The demonstration of the organism in the mouths of a substantial proportion of dyspeptic patients has major implications for the spread of H pylori and identifies a potential source for reinfection following eradication of the organism from the stomach.

The mutagenic activity of gastric juice.

The mutagenic activity of fasting gastric juice was assessed in 123 patients including 18 with normal endoscopic findings, 53 peptic ulceration, 9 gastric cancer, 12 pernicious anaemia and 31 patients who had undergone peptic ulcer surgery in the past. Significant mutagenic activity was detected in 96 (78%). Marked variations in mutagenic activity were noted both within and between the patient groups and no significant differences were detected. No correlation was found between mutagenic activity and patient age or sex, gastric pH, bile acid concentrations or bacterial counts, intestinal metaplasia on gastric mucosal biopsy, or intragastric nitrite. About 30% of gastric juice samples showed evidence of a cytotoxic activity towards the Salmonella tester strains in the mutation assay. Preliminary studies on other body fluids showed the presence of significant mutagenic activity in fasting saliva, bile and plasma. These findings demonstrate widespread human exposure to potentially genotoxic substances.

Oral bowel lavage preparation for colonoscopy.

Colonoscopy is a commonly performed diagnostic and therapeutic procedure in most general hospitals, which requires effective bowel preparation to be worthwhile. We report the effect of replacing a diet, laxative and bowel washout preparation with oral bowel lavage using a balanced electrolyte formulation, in our unit. The preparation was acceptable to patients, medical and nursing staff, generally preferred to previous preparations by those who had experienced them, allowed a more complete colonoscopy with an excellent quality of view, and was less expensive in nursing time. We regard oral bowel lavage as currently the method of choice for bowel preparation prior to colonoscopy in the majority of patients.

Permeability of the small intestine to substances of different molecular weight.

The permeability of the rabbit small intestine has been studied by measuring the plasma clearances of water-soluble molecules over the molecular weight range 60-33,000. An inverse relationship has been demonstrated between permeability and molecular weight. The significance of these findings in relation to current concepts of the ;pore hypotheses' is discussed, and the possible physiological and pathological implications are considered.

Bacteraemia with upper gastrointestinal endoscopy--a reappraisal.

To assess the risk of infective endocarditis for susceptible patients having upper gastrointestinal (GI) endoscopy, we have prospectively studied the incidence, level, duration and source of endoscopy-related bacteraemia and the microorganisms involved. Blood was drawn for aerobic and anaerobic culture and pour plate estimation from 50 patients undergoing upper GI endoscopy. Blood cultures were positive in two patients with the isolation of Streptococci and other oropharyngeal organisms during and 5 min after endoscopy. Pre-endoscopy salivary cultures in both patients grew Streptococci identical to those isolated from the blood; pour plates were negative. We conclude that though the risk of infective endocarditis after upper GI endoscopy is probably very low, the finding of a 4% incidence of transient low-level bacteraemia of oropharyngeal origin argues for antibiotic prophylaxis for susceptible patients.

Double-blind clinical, endoscopic and histological comparison of hydrotalcite/dimethicone suspension and magnesium hydroxide/aluminum hydroxide suspension in the treatment of symptomatic gastritis.

A double-blind, randomized trial was undertaken to compare the clinical, endoscopic and histological response to 6-weeks' treatment with hydrotalcite/dimethicone suspension or magnesium hydroxide/aluminum hydroxide suspension in 36 patients with symptomatic gastritis. Significantly more patients (P less than 0.05) showed symptomatic improvement in the antacid-treated group than in the hydrotalcite/dimethicone-treated group and more had a reduction in histological inflammatory scores (P less than 0.01), although there was little correlation between histology and symptoms. There was no evidence from this study that the bile acid binding and anti-foaming properties of hydrotalcite/dimethicone suspension were of any benefit in the treatment of patients with symptomatic gastritis.

Effect of cimetidine on the gastric bacterial flora.

Bacteriological studies were carried out on samples of gastric juice obtained from 31 patients with peptic ulcer before and immediately after a month's course of cimetidine. After cimetidine there were major increases in both total bacterial counts and counts of nitrate-reducing organisms and qualitative changes suggesting the establishment of a flora which included large numbers of "faecal" organisms.

Simultaneous culture of saliva and jejunal aspirate in the investigation of small bowel bacterial overgrowth.

Both saliva and jejunal aspirate were cultured from 22 patients with suspected small bowel bacterial overgrowth and from eight controls. Large numbers of organisms (greater than 10(6)/ml) were recovered from the jejunal aspirate of 16 subjects, in five of whom the same organisms were present in similar relative proportions in the saliva, suggesting contamination of the sample with saliva, while in 11 the jejunal organisms differed from those in saliva. In eight of these the jejunal flora was a typical 'faecal' flora usually associated with small bowel bacterial overgrowth but, in three, the jejunal floral was superficially similar to that of saliva. Distinct subpopulations of bacteria, typically Gram-positive non-sporing rods, were, however, evident in the jejunum of these patients, and were also recovered, in smaller numbers, from the jejunum of controls, suggesting that they form a distinct jejunal microflora. Culture of saliva in addition to jejunal aspirate may be useful in the recognition of contamination of the proximal small bowel with saliva, and in the diagnosis of small bowel bacterial overgrowth.

Helicobacter pylori infection and dental care.

Sixty two patients (mean age 45.6 years) were assessed for oral hygiene and periodontal disease by dental examination before endoscopy. Information about oral care, smoking, and dentures was obtained and samples of dental plaque collected. The presence of Helicobacter pylori in plaque as sought by culture and polymerase chain reaction (PCR), and gastric antral biopsy specimens were taken for histological examination. Although H pylori was detected in the antral specimens of 34 patients (54%) all of the cultures of dental plaque were negative, and PCR was only positive from the dentures of one patient. Smokers had poor oral hygiene, visited their dentist less often, and brushed their teeth less frequently. There was no correlation of H pylori gastritis with either dental hygiene or periodontal disease. These results suggest that dental plaque or dentures are not an important reservoir for H pylori and are probably not a significant factor in transmission of the organism. The conflicting results in published works may be caused by differences in sample collection, culture techniques, or oral contamination from gastric juice as a result of gastro-oesophageal reflux at the time of endoscopy.