Helicobacter pylori: a human pathogen.
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Anti-Bacterial Agents↗
Biomedical subjects
J J Misiewicz
Publications and source records attributed to J J Misiewicz.
Hitting H pylori for four.
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Anti-Ulcer Agents↗
Effects of acid suppression on microbial flora of upper gut.
Decreased acid secretion, due to therapy or disease, predisposes to increased bacterial counts in gastric juice. As bacterial numbers increase, the number of nitrate-reducing strains and the concentration of luminal nitrite usually also increase. However, there is controversy (mainly because of assay problems) about whether decreased acid increases generation of N-nitroso compounds: these may be produced by acid or by bacterial catalysis, and the relative contributions of each are still uncertain. Other potentially important factors include ascorbate secretion (can prevent nitrite conversion to nitroso compounds) and the particular spectrum of nitroso compounds produced. Nitrosation of several histamine H2-receptor antagonists has been demonstrated experimentally, but under conditions that are very unlikely to be encountered clinically. Some acid suppressant therapies have been claimed to aid eradication of Helicobacter pylori, but more work is needed to evaluate this. If ulcer treatment regimens do not also address eradication of H. pylori (when present), gastritis will progress, and the recently documented association between H. pylori and gastric carcinoma needs to be considered. Enteric flora probably also increase if acid secretion is markedly reduced: this does not appear to have nutritional consequences but probably reduces the resistance to occasional infections, of which cholera is the best documented.
Antacids↗
Eradication of Helicobacter pylori.
Although there are numerous publications reporting eradication results, the general picture is confused by the bewildering multiplicity of treatment schedules employed by the various workers. The over-riding need now is for large scale trials, and more especially for direct comparisons of different treatment regimens in the same populations of patients. Such data are entirely absent from the literature at present. Standardization of definitions and of methodology pertaining to diagnosis of eradication, recording of side effects, measurement of compliance and determination of recurrence or of reinfection, is badly needed. As the definition of eradication remains arbitrary, it is important to include genome fingerprinting techniques in the long-term follow-up for recurrence, so that the question of reinfection versus recrudescence can be examined (Bell et al, 1993b; Xia et al, 1994). Because of the wide differences in the agents used in H. pylori eradication therapies, proper double-blinding of treatment trials remains a difficult problem. This can be dealt with to some extent by ensuring that the interpretation of tests for H. pylori eradication is performed by personnel unaware of the clinical details. Review of the existing data on eradication of H. pylori indicates that clinically useful results can be achieved in some 70 to 95% of patients, on an intention to treat basis. Compliance, side effects and resistance to metronidazole remain the limiting factors. Efficacy, freedom from side effects, simplicity and low cost will determine the success of any regimen in the future. At present, it is not possible to make firm recommendations in favour of one regimen over another, but it seems reasonable to forecast that dual therapies consisting of a PPI and an antibiotic will receive much attention. Preparations consisting of an H2RA associated with a bismuth compound, which are used together with an antibiotic are an interesting approach. Compliance should be as good as with a normal dual therapy and the eradication results look promising (Wyeth et al, 1994; Webb et al, 1994). The advantages of dual therapies that include a PPI lie in their simplicity, in not relying on imidazole for their anti-H. pylori effect but on the profound inhibition of acid output produced by the PPI. Thus PPI based dual therapy can probably evoke better compliance than the more complicated regimens. The use of PPIs has other advantages in addition to decreasing the MIC90 of the antibiotic combined with it. This is because administration of a powerful inhibitor of gastric acid secretion, such as a PPI, will aid the rapid healing of an ulcer crater and will rapidly relieve the symptoms of peptic ulceration. Gastrin releasing peptide-stimulated acid secretion is raised in duodenal ulcer patients to approximately sixfold over control levels according to El-Omar et al (1993b), and although it returns to normal following the eradication of H. pylori, this process takes time to become effective (El-Omar et al, 1993a). Suppression of acid output provides an immediate therapeutic shield, while the decrease in inflammation and acid output secondary to H. pylori eradication can be established. The most widespread resistance to antibiotics exhibited by H. pylori is with respect to imidazoles. The prevalence of metronidazole resistance is widespread in the emergent countries (Glupczynski et al, 1990), but it is also appreciable in the West, especially in women, who may have been given metronidazole in the treatment of pelvic infections (Rautelin et al, 1992; Banatvala et al, 1994). Moreover, H. pylori becomes resistant to metronidazole very easily and often as a result of treatment which includes an imidazole compound (Malfertheiner, 1993; Banatavala et al, 1994). On the other hand, H. pylori resistance to macrolides is not widespread and does not develop easily during their administration. It is difficult to forecast which antibiotic will be the most widely used agent
Anti-Bacterial Agents↗
Eradication of Helicobacter pylori with lansoprazole and clarithromycin.
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.
2-Pyridinylmethylsulfinylbenzimidazoles↗
Eradication of Helicobacter pylori and prevention of recurrence of duodenal ulcer: a randomized, double-blind, multi-centre trial of omeprazole with or without clarithromycin.
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%.
Adult↗
Changes in the intragastric distribution of Helicobacter pylori during treatment with omeprazole.
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.
Acute Disease↗
Helicobacter pylori and upper gastrointestinal disease: a survey of gastroenterologists in the United Kingdom.
The objective of this study was to conduct a survey of the opinions and practices of gastroenterologists in the United Kingdom concerning the impact of Helicobacter pylori infection on the management of upper gastrointestinal diseases. A postal questionnaire was sent to all medically qualified members of the British Society of Gastroenterology working in the UK. Replies were received from 670 of 1037 eligible BSG members (65%). Of these, 73% thought that H pylori was a cause of duodenal ulcer and 84% thought that eradication of H pylori decreased ulcer recurrence in comparison with acid suppression. While 80% used anti-H pylori therapy for a chronic relapsing duodenal ulcer, only 25% used such therapy for an ulcer at first presentation and 17% never used anti-H pylori therapy for patients with duodenal ulcer. Although 75% of respondents did not agree that H pylori was a cause of non-ulcer dyspepsia, 69% used anti-H pylori therapy to treat a patient with this condition. At the time of the survey, 69% of those who used anti-H pylori therapy adopted some variant of standard triple therapy. Only 7% routinely tested for bacterial sensitivity to antibiotics and only 22% assessed their patients for eradication after treatment. There was a lack of consensus about whether H pylori was a cause of gastric ulcer or gastric cancer with only 47% and 17% respectively believing in these associations. In conclusion, at the time of the survey, the use of anti-H pylori therapy had been accepted by a majority of specialist UK gastroenterologists in the management of upper gastrointestinal disease. There was, however, a substantial degree of uncertainty and divergence about which patients should be treated.
Adult↗
Current insights in the pathogenesis of Helicobacter pylori infection.
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Helicobacter Infections↗
Antibiotic treatment for low-grade gastric MALT lymphoma.
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Anti-Bacterial Agents↗
Platelets in ulcerative colitis and Crohn's disease express functional interleukin-1 and interleukin-8 receptors.
Tissue and plasma concentrations of several cytokines are increased in patients with inflammatory bowel disease (IBD). Platelets play an important role in inflammation and circulate in an activated state in patients with IBD. This study assesses the expression of IL-8 and IL-1 receptors on the surface of platelets from patients with IBD using phycoerythrin (PE)-labelled recombinant human rhIL-1 beta and rhIL-8 and flow cytometry. The percentage IL-1R expressing platelets (median and interquartile range IQR) in the IBD group was 8.7% (5.5-18.2) compared to 4.2% (2.3-6.1) in controls (P = 0.02). The percentage IL-8R expressing platelets in the IBD group was 22.5% (16.5-27.9) and 9.2% (4.3-9.6) in controls (P < 0.001). Furthermore, platelet IL-1R expression in patients with IBD was inversely related to the total daily dose of steroids (r = 0.71, P < 0.01 linear regression analysis). Finally, platelet rich plasma from healthy controls was stimulated with rhIL-1 beta and rhIL-8 and assessed for activation dependent expression of platelet aGPIIb/IIIa and CD62 (p-selectin, GMP-140). IL-1 beta and IL-8 in vitro significantly and specifically activated the platelets. The surface membrane of platelets is able to express functional IL-1R and IL-8R, the expression of which is significantly increased in IBD. Interleukin-1 beta and IL-8 modulate platelet activation in vitro indicating a target role for platelet function in inflammation.
Adolescent↗
One week's anti-Helicobacter pylori treatment for duodenal ulcer.
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.
Adolescent↗
Palliation of malignant dysphagia by ethanol induced tumour necrosis.
Thirty two patients (74 (43-93) years; median, (range)) with dysphagia because of inoperable, unresectable or recurrent oesophagogastric carcinoma were treated by ethanol induced tumour necrosis (ETN). Endoscopic injection of absolute alcohol was performed using a variceal injector needle, with 0.5-1 ml aliquots injected retrogradely from distal to proximal tumour margin. Dilatation to 12 mm was used only if the endoscope would not traverse the stricture. In patients with total occlusion, injection into the proximal tumour was followed by a repeat endoscopy 3-7 days later. Dysphagia was graded from 0 = no dysphagia to 4 = total dysphagia. The significance of changes in the dysphagia grade after ETN were assessed using the Wilcoxon rank sum test. Results (median (range)) were as follows: stricture length = 5.0 cm (1-15). Dysphagia grade before treatment was 3 (2-4) improving after first treatment to 1 (0-3), p < 0.003. Best dysphagia grade achieved was 1 (0-3) and interval between treatments was 28.5 days (4-170). The volume of ethanol injected = 10 ml (1.5-29) and survival after first treatment was 93 days (6-660). The number of treatment sessions required to achieve best grade = 1 (1-3). There were no treatment complications. ETN significantly improves dysphagia. Results of palliation are similar to those of laser therapy, but can be achieved quickly and safely on a day case basis in most patients and at a small proportion of the cost.
Adult↗
Eradication of Helicobacter pylori with clarithromycin and omeprazole.
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.
Adult↗
Pelvic floor function in multiple sclerosis.
The aim of this study was to define pelvic floor function in patients with multiple sclerosis and bowel dysfunction, either incontinence (MSI) or defecation difficulties without incontinence (MSC). Normal controls and patients with idiopathic neurogenic faecal incontinence without multiple sclerosis (FI, disease controls) were also studied. Thirty eight multiple sclerosis patients (20 incontinent, 18 incontinent) 73 normal controls, and 91 FI patients were studied. The FI group showed the characteristic combined sensorimotor deficit previously described in these patients of low resting and voluntary contraction and pressures, increased sensory threshold to mucosal stimulation, and increased pudendal nerve terminal motor latencies and fibre densities. MSI patients had significantly lower anal resting pressures (80 (30-140) cm H2O, median (range) v 98 (30-200), normal controls, p = 0.002) and both MSC and MSI patients had significantly lower anal maximum voluntary contraction pressures (65 (0-260) cm H2O, MSC and 25 (0-100), MSI v 120 (30-300), normal controls, p = < 0.0004) and higher external anal sphincter fibre densities (1.7 (1.1-2.6), MSC and 1.7 (1.1-2.4), MSI v 1.5 (1.1-1.75), normal controls, p < 0.006) compared with normal controls but pudendal nerve terminal motor latencies were similar and no sensory deficit was found. This contrasted with the idiopathic faecal incontinent patients who, in addition to significantly higher fibre densities (1.8 (1.1-3), p = 0.001) had increased pudendal latencies (2.5 (1.1-5.5) mS v 2.08 (1.4-2.6), p = 0.001) compared with normal controls. The idiopathic faecal incontinent group had significantly lower resting anal pressures (50 (10-160) cm H2O, p=0.02) than the MSI group. Comparison with the incontinent and continent multiple sclerosis groups showed that incontinence was associated with lower voluntary anal contraction pressures (25 (0-100) v 65 (0-260), p=0.03) but that there were no other differences between these two groups. Pelvic floor function is considerably disturbed in multiple sclerosis, showing muscular weakness with preservation of peripheral motor nerve conduction, providing indirect evidence that this is mainly a result of lesions within the central nervous system.
Adult↗
Two-week eradication regimen for metronidazole-resistant Helicobacter pylori.
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%.
Adolescent↗
Cephalic phase of colonic pressure response to food.
A cephalic phase of colonic pressure response to food was sought in five normal subjects (mean age (22.6) years, 22-24), studied on six separate occasions by recording intraluminal pressures in the unprepared sigmoid colon. Gastric acid secretion was measured simultaneously by continuous aspiration through a nasogastric tube. After a 60 minute basal period, one of five 30 minute food related cephalic stimuli, or a control stimulus was given in random order; records were continued for a further 120 minutes. The cephalic stimuli were: food discussion, sight and smell of food without taste, smell of food without sight or taste, sight of food without smell or taste, and modified sham feeding; the control stimulus was a discussion of neutral topics. Colonic pressures were expressed as study segment activity index (area under curve, mm Hg.min) derived by fully automated computer analysis. Gastric acid output was expressed as mmol/30 min. Food discussion significantly (p < 0.02, Wilcoxon's rank sum test) increased colonic pressure activity compared with control or basal activity. Smell of food without sight or taste also significantly (p < 0.03) increased the colonic pressure activity compared with control and basal periods. Sham feeding and sight and smell of food without taste significantly (p < 0.02 and p < 0.03) increased colonic pressures compared with control but not basal activity. The increase in colonic activity after sight of food without smell or taste was not significantly different from control or basal activity (p = 0.44 and p = 0.34). Food discussion was the strongest colonic stimulus tested. Food discussion and sham feeding significantly (p<0.02) stimulated gastric acid output above control and basal values. Sight and smell of food without taste significantly (p<0.02) increased acid output above basal. Smell of food without sight or taste and sight of food without smell or taste did not significantly (p=0.06, p=0.34) increase acid output. In contrast with the effect on colonic pressures, sham feeding was the best stimulus of acid output. Increased colonic pressure activity after food discussion correlated significantly (r=0.45, p<0.02) with gastric acid output. There was no correlation (r=-0.1, p>0.5) between colonic pressure activity and gastric acid output in the control study. These data show that there is a cephalic phase of the colonic response to food.
Adult↗
Colonic motility: practice or research?
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Colon↗