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Publications and source records attributed to J H Baron.
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BACKGROUND: Patients with duodenal ulcer (DU) have high basal (BAO) and peak (PAO) acid outputs. The effect of Helicobacter pylori eradication on these variables is unclear. AIM: To discover if gastric acid hypersecretion in patients with DU is caused by H pylori. PATIENTS AND METHODS: BAO, gastrin releasing peptide (GRP), and pentagastrin stimulated PAO in 10 H pylori negative controls, and in 10 H pylori positive patients with DU was measured before and six months after H pylori eradication. H pylori status was determined by histology, culture, and by the 13C-urea breath test. After collecting a 30 minute basal aspirate, GRP 40 pmol/kg/h was infused for 45 minutes, and after a 30 minute washout, pentagastrin 6 micrograms/kg was injected intramuscularly. RESULTS: Basal and stimulated acid output (PAOGRP and PAOPg) were significantly higher in H pylori positive DU than in H pylori negative controls. Six months after H pylori eradication, basal and stimulated acid outputs were all significantly lower than before H pylori eradication. CONCLUSIONS: This study has shown that BAO, PAOGRP, and PAOPg are higher in H pylori positive DU than in H pylori negative controls. All decreased significantly six months after H pylori eradication, to fall within the range of controls. These results are compatible with a hypothesis that acid hypersecretion in duodenal ulcer disease is caused by H pylori infection.
BACKGROUND: Factors that determine gastric metaplasia in the duodenal bulb are ill defined. It is more common and extensive in the presence of high acid output and possibly in the presence of Helicobacter pylori. However, no quantitative relation between acid output and the extent of gastric metaplasia has been demonstrated and its relation to H pylori is uncertain. AIM: To determine the relation between H pylori infection and acid output and the presence and extent of gastric metaplasia in the duodenal bulb. subjects: H pylori positive and negative patients with duodenal ulcer and healthy controls were studied. METHODS: Quadrantic duodenal bulb biopsy specimens were taken and the presence and extent of gastric metaplasia determined using a computer enhanced image intensifier. Basal and stimulated acid outputs were measured. RESULTS: gastric metaplasia was significantly (p < 0.05 more common and significantly (p < 0.05) greater in extent in patients with duodenal ulcer than in controls. Neither the prevalence or extent of gastric metaplasia was affected by H pylori status. There were significant (p < 0.01) direct correlations between acid output and extent of gastric metaplasia. CONCLUSIONS: Prevalence and extent of gastric metaplasia are not related to H pylori in controls, or in patients with duodenal ulcer. Rather, high acid response to gastrin may be more important.
AIM: To investigate the prevalence, and relation to Helicobacter pylori, of parietal cells in the duodenal bulb using a monoclonal antibody directed against H+,K(+)-ATPase (HK12.18). METHODS: Twenty six patients with duodenal ulcer disease and 16 healthy controls were studied. H pylori status was determined by gastric histology and culture and by the 13C-urea breath test. Four biopsy specimens were taken from the duodenal bulb and stained with HK12.18. The presence/absence and number of parietal cells in the duodenal bulb were assessed blindly by a histopathologist. RESULTS: The overall prevalence of parietal cells in the duodenal bulb was 31% (13/42) and was similar in patients with duodenal ulcer and in controls, and in H pylori positive and negative subjects. The median (range) number of parietal cells in the duodenal bulb was 7.5 (4-20) parietal cells/subject, and was similar in all four groups. CONCLUSIONS: The prevalence of parietal cells in the duodenal bulb (31%) is notably higher than previously reported in endoscopic studies, and is in keeping with reports from studies on necropsy/operative specimens. There was no difference in the prevalence or number of parietal cells in the duodenal bulb between patients with duodenal ulcer and controls, regardless of H pylori status. These findings suggest that parietal cells in the duodenal bulb do not contribute to the pathogenesis of duodenal ulcer.
BACKGROUND: Changes in gastroduodenal blood flow have been implicated in the pathogenesis of duodenal ulcer. We have studied duodenal blood flow during the development of an acute to chronic duodenal ulcer by using the abscopal model, in which ulcers are generated as an indirect effect of lower mediastinal irradiation. METHODS: Female CFLP mice (n = 108) weighing 25-40 g were randomly allocated to one of three groups. Controls were not irradiated. Irradiated 'controls' received 18 Gy 250 kV X-rays to the upper mediastinum (which does not cause duodenal ulceration). The lower mediastinum group received the same dose of irradiation, which has been shown to induce typical chronic duodenal ulcers in 45% of animals so treated. Animals were studied by means of radiolabelled microspheres 3 or 7 days later (that is, during and at the end of the lag period for ulcer induction). RESULTS: Proximal duodenal blood flow specifically was reduced by 32% in the lower mediastinum group compared with irradiated controls at 7 days (4.3 versus 6.3 ml/g tissue/min; P = 0.025 by ANOVA with contrast); there was no significant difference in blood flow to the stomach and to the distal duodenum. The decrease in proximal duodenal blood flow in the lower mediastinum group did not differ in the five animals that developed ulcer compared with the seven that did not. CONCLUSION: Although there is an overall decrease in duodenal blood flow associated with chronic duodenal ulcer, reduced blood flow may not explain individual susceptibility to ulceration.
BACKGROUND: This study determines the efficacy and safety of a 1-week triple therapy regimen of lansoprazole, clarithromycin and metronidazole in an area with a high prevalence of pre-treatment metronidazole-resistant strains of Helicobacter pylori. METHODS: Seventy-five H. pylori positive patients with gastritis or duodenal ulcer were entered into an open study of lansoprazole 30 mg o.m., clarithromycin 250 mg b.d. and metronidazole 400 mg b.d. H. pylori status was determined by CLOtest, histology, culture and by 13C-urea breath test (repeated > or = 28 days after treatment). RESULTS: Seventy-one patients completed the treatment and returned for follow-up. H. pylori was eradicated in 61 of 71 (86%) patients by per-protocol analysis, and in 61 of 75 (81%) patients by intention-to-treat analysis. H. pylori was eradicated in 12 of 16 (75%) patients with metronidazole-resistant strains compared with 22 of 24 (92%) in patients with metronidazole-sensitive strains of H. pylori (P = 0.14). Fourty-five patients reported at least one adverse event, and three patients stopped treatment due to them (two with headaches and one with diarrhoea). CONCLUSIONS: A 1-week course of lansoprazole 30 mg o.m., clarithromycin 250 mg b.d. and metronidazole 400 mg b.d. eradicates H. pylori in up to 86% of patients. It is of proven benefit in patients with pre-treatment metronidazole-resistant strains of H. pylori.
1. The content and distribution of carbohydrate was examined in mucus glycopolypeptides from human antral mucosae. 2. The mean amount of carbohydrate per 1000 amino acid residues was found to be similar in glycopolypeptides with A, B or H activity. It was slightly, though significantly, less in glycopolypeptides lacking these determinants, because carbohydrate chains were of a shorter average length than in the A-, B- or H-active preparations. This difference was reflected in the sizes of oligosaccharide-alcohols released from representative glycopolypeptides with alkaline borohydride. 3. Differences between A-, B- or H-active and non-secretor glycopolypeptides in terms of the mean number of carbohydrate chains per 1000 amino acid residues were found to be small, and without significance. 4. The average number of peripheral monosaccharide units per 1000 amino acid residues was greater in A-active than in H-active, and least in non-secretor, glycopolypeptides. This order was reversed for monosaccharide units incorporated into skeletal (core plus backbone) structures. The difference in each case was statistically significant. 5. These findings suggest that the increased risk of peptic ulcer associated with blood group O and non-secretor status is unlikely to be attributable to an inherent deficiency in the protective mucus layer, linked to differences between mucins that are associated with A, B or H activity. Other hypotheses linked to infection with Helicobacter pylori are examined.
BACKGROUND: Helicobacter pylori eradication with omeprazole and clarithromycin varies between 40 and 80%. The dose, frequency and duration of treatment may account for these differences. Lansoprazole, a recently introduced proton pump inhibitor, is a more potent H. pylori bacteriostat in vitro than omeprazole. The aim of this open, comparative, randomized study was to investigate the efficacy and safety of lansoprazole 30 mg once or twice a day (and for 2 vs. 4 weeks) plus clarithromycin 500 mg t.d.s. for 2 weeks. in the eradication of H. pylori. METHODS: Sixty-six patients with H. pylori infection received clarithromycin 500 mg t.d.s. for 2 weeks and one of four lansoprazole regimens: 30 mg once a day for 2 (Group 1, n = 16) or 4 (Group 2, n = 16) weeks, or 30 mg b.d. for 2 (Group 3, n = 18) or 4 (Group 4, n = 16) weeks. H. pylori eradication was determined by the 13C-urea breath test 4 weeks after finishing treatment. RESULTS: Per protocol analysis (53 patients) shows that H. pylori was eradicated in 6/13 (46%) in Group 1, 7/13 (54%) in Group 2, 9/14 (64%) in Group 3 and 9/13 (69%) in Group 4. Thirty-one of 68 patients experienced side effects. Analysis on an intention-to-treat basis gave similar results. CONCLUSION: The dose of lansoprazole appears to be more important than the duration of therapy. Dual therapy with lansoprazole and clarithromycin should be investigated further as a possible treatment regimen for H. pylori infection.
BACKGROUND: Antimicrobial treatment for Helicobacter pylori eradication is currently recommended for all patients with duodenal ulcer disease, but consensus on the best treatment is lacking. METHODS: Patients with active duodenal ulcer and H. pylori were enrolled in a double-blind, randomized, placebo-controlled multi-centre study. Patients received omeprazole 40 mg daily for 28 days and either clarithromycin 500 mg t.d.s. or placebo t.d.s. for the first 14 days. Patients underwent endoscopy before starting treatment, at 2 weeks, immediately after stopping treatment if unhealed at 2 weeks, and at 1, 6 and 12 months after the end of treatment, or at the recurrence of symptoms. Eradication of H. pylori, duodenal ulcer healing and ulcer recurrence were measured. RESULTS: One-hundred and fifty-four patients were recruited and randomized to omeprazole plus clarithromycin (n = 74) or to omeprazole plus placebo (n = 80). One month after treatment, H. pylori was eradicated in 57 of 69 (83%; 95% CI: 72-91%) patients receiving omeprazole plus clarithromycin, compared with 1 of 75 (1%; 95% CI: 0-7%) receiving omeprazole alone (P < 0.001). In patients receiving omeprazole plus clarithromycin the ulcer healed at 2 weeks in 83% (95% CI: 71-91%) and at 4 weeks in 100% (95% CI: 95-100%), compared with 77% (95% CI: 66-86%) and 97% (95% CI: 91-100%) in those given omeprazole plus placebo (N.S.). Ulcers recurred at 12 months in 6% (95% CI: 1-16%) of patients given omeprazole plus clarithromycin, compared with 76% (95% CI: 63-86%) of patients given omeprazole plus placebo (P < 0.001). The incidence of side-effects was similar in both treatment groups (38% with clarithromycin dual therapy and 29% with omeprazole plus placebo; P = 0.304). Ninety per cent of patients took at least 90% of their prescribed medication. CONCLUSIONS: Omeprazole plus clarithromycin dual therapy eradicated H. pylori in 83% of patients with duodenal ulcer and significantly decreased 12-month recurrence from 76% to 6%.
Omeprazole is a powerful inhibitor of gastric acid and may suppress Helicobacter pylori by effecting the pKa of H pylori urease, by altering the pattern of infection, or by promoting overgrowth of other bacteria. At routine endoscopy H pylori was detected by histology and culture before and after four weeks' treatment with omeprazole, 40 mg each morning. A 13C-urea breath test was also done at t = 0, 2, 4, and 6 weeks. Thirty nine patients with duodenal ulcer (n = 25) or reflux oesophagitis (n = 14) were studied, of whom 29 of 39 had H pylori infection. During omeprazole treatment, 13C-urea breath test values fell significantly--mean (SEM) values before treatment and at four weeks were 23.0 (2.1) and 15.5 (2.7) per mil respectively, p < 0.001. Before treatment H pylori was seen in 28 of 29 antral, 29 of 29 corpus, and 28 of 29 fundic biopsy specimens. After four weeks of omeprazole treatment, the histological density of H pylori in the antrum and corpus was reduced (p < 0.001), while that in the fundus was increased. The migration of H pylori from the antrum to the fundus was associated with a corresponding decrease in the activity of antral gastritis. H pylori was not seen in antral biopsy specimens from 12 of 29 patients whose median excess delta 13CO2 excretion fell from 23.0 to 9.9 per mil. In the body mucosa, 26 of 29 specimens were still positive for H pylori and there was no significant change in the gastritis type. Two weeks after finishing treatment, the mean (SEM) excess delta 13CO2 excretion returned to levels before treatment. Omeprazole decreases antral H pylori colonisation but increases that in the fundus. The changes in the intragastric distribution of the organism are associated with concomitant changes in the activity of gastritis and are matched by a progressive fall in the excretion of delta 13CO2.
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Duodenum exposed to above threshold gastric acid secretion may ulcerate if infected with Helicobacter pylori. Duodenal ulcers can be healed by suppressing acid secretion medically or surgically; their recurrence can be prevented by lifelong antisecretory drugs or by an elective vagotomy. However, duodenal and gastric ulcers can now be healed, and recurrence prevented, without operation by eradication of H. pylori.
This open study tested whether eradication of Helicobacter pylori (H pylori) heals duodenal ulcers as well as decreasing recurrence. H pylori was detected in patients with endoscopic duodenal ulcers by histology, CLO-test, culture, and 13C-urea breath test (13C-UBT). Tripotassium dicitrato bismuthate (120 mg) and amoxycillin (500 mg) each four times daily, were given for seven days, with 400 mg metronidazole five times a day on days 5-7. The 13C-UBT was repeated immediately after treatment and endoscopy repeated within 21 days. After treatment unhealed ulcers were reinspected one month later and healed ulcers followed up by 13C-UBT alone for 12 months. Of 45 patients, 44 were available for follow up. Mean pretreatment excess delta 13CO2 excretion was 25.6 per mil, which fell to 2.4 per mil immediately after finishing treatment, indicating clearance of H pylori in every patient. At the second endoscopy (median interval 20 days from start of treatment) 33 of 44 (75%) duodenal ulcers had healed. Ten of the remaining 11 duodenal ulcers were smaller and those 10 healed in the next two weeks with no further treatment. Two patients' ulcers that initially healed with clearance of H pylori recurred three weeks later (both had metronidazole resistant H pylori). H pylori was eradicated in 28 of 44 (64%) patients (13C-UBT negative for median follow up 10.2 months). Overall 41 of 43 (93%, 95% confidence intervals 81%-99%) duodenal ulcers were healed at one month. This study suggests that one week of anti-H pylori triple treatment is effective in healing duodenal ulcers.
Clarithromycin, a new and well tolerated, acid stable macrolide antibiotic, has a similar antimicrobial spectrum to erythromycin but a better in vitro MIC90 (0.03 microgram/l-1) against Helicobacter pylori (H pylori). This study aimed at determining the eradication rate using clarithromycin 500 mg thrice daily and omeprazole 40 mg daily for two weeks. Patients were given an endoscopy and H pylori status assessed by antral culture (microaerobic conditions, for up to 10 days), antral and corpus histology tests (haematoxylin and eosin/Gimenez stains), and 13C-urea breath test (13C-UBT, European standard protocol, positive result = excess delta 13CO2 excretion > 5 per mil). Compliance was assessed by returned tablet counts. H pylori clearance at the end of treatment and eradication four weeks after finishing treatment were assessed by the 13C-UBT. Seventy three patients (54 men, median age 45 years) with duodenal ulcers (n = 42) or duodenitis/non-ulcer dyspepsia (n = 31) all with a positive 13C-UBT (mean (SEM) excess delta-13CO2 excretion = 26.6 (4.9) per mil) and either positive antral histology (n = 72) or positive antral culture (n = 35) were studied. Before treatment 2/27 (7%) isolates of H pylori were resistant to clarithromycin and five isolates were resistant to metronidazole. In 70/73 (96%) the 13C-UBT was negative immediately after finishing treatment. Four weeks later the 13C-UBT was negative in 57/73 (mean (SEM) excess delta 13CO2 excretion = 1.2 (0.3) per mil, eradication rate = 78%). Forty eight (66%) patients experienced a metallic taste while taking the tablets. Although four (5%) patients, however, could not complete the course of treatment, in only one of these four was H pylori not eradicated. These results show that duel therapy with clarithromycin and omeprazole is well tolerated. With an eradication rate of 78% it is an effective treatment for metronidazole resistant H pylori and may be an alternative to standard triple therapy.
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At present there is no generally accepted treatment regimen for eradicating metronidazole-resistant Helicobacter pylori. This study determines the eradication rate after treatment with 40 mg omeprazole o.m. and 500 mg amoxycillin q.d.s. for 14 days, with 120 mg tripotassium dicitrato bismuthate q.d.s. for the first week (Days 1-7) and 750 mg ciprofloxacin b.d. for the second week (Days 8-14). Thirty patients (16 male, mean age 45 years, range 16-80 years) with duodenal ulcers (n = 18) or non-ulcer dyspepsia (n = 2) and metronidazole-resistant H. pylori detected by histology, culture, in vitro sensitivity tests and a positive 13C-urea breath test entered the study. Follow-up was by 13C-urea breath test at the end of treatment and at 1, 3, 6, and 12 months. Eradication was defined as a negative 13C-urea breath test at least 1 month after finishing treatment. H. pylori was successfully eradicated in 21/30 (71%) patients (median follow-up 10.2 months, range 4-12 months). A pre-treatment ciprofloxacin-resistant strain was isolated in 1/9 patients in whom eradication failed. Of 30 patients 29 completed the 2-week regimen; one patient experienced dizziness after 3 days of treatment. The most common side-effect was increased stool frequency (n = 6). This 2-week treatment regimen for metronidazole-resistant H. pylori is well tolerated and achieves an eradication rate of 70%.