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J C Delchier

Publications and source records attributed to J C Delchier.

At least 19 recordsLinked to original sources

Clarithromycin resistance of Helicobacter pylori has a major impact on the efficacy of the omeprazole-amoxicillin-clarithromycin therapy.

Clarithromycin resistance of Helicobacter pylori is relatively frequent in France and is assumed to be the main cause of failure of the proton pump inhibitor-amoxicillin-clarithromycin (PPI-AC) therapy, which is the first-line regimen in our country. We determined the respective effects of clarithromycin primary and secondary resistances on efficacy of the PPI-AC regimen and examined whether failures were associated with persistence of the same strain or with emergence of a new one. Hundred and twenty three H. pylori-infected patients were treated for seven days with omeprazole 20 mg b.d., amoxicillin 1 g b.d., and clarithromycin 500 mg b.d. Eradication was assessed by breath test in 102 patients. MICs of clarithromycin were determined by E-test. Strain genotyping was performed by random amplified polymorphic DNA. The pre-treatment and post-treatment prevalences of clarithromycin resistance were 18.7% (23/123) and 69.2% (9/13), respectively. The rates of eradication were 67.6% (69/102), 78.8% (67/85), and 11.8% (2/17) for all, susceptible and resistant strains, respectively. The post-treatment isolate was available for six patients with a susceptible pre-treatment isolate and a persistent infection; resistance emerged in two patients and was associated with persistence of the pre-treatment strain in one and with selection of a new strain in the other. In conclusion, in our hospital, failures of the PPI-AC therapy are related to both clarithromycin primary and secondary resistances but emergence of secondary resistance does not explain all failures in the initial clarithromycin-susceptible group. In that group a new strain can emerge after failure.

Adolescent↗

Impact of Helicobacter pylori resistance to clarithromycin on the efficacy of the omeprazole-amoxicillin-clarithromycin therapy.

BACKGROUND: Helicobacter pylori resistance to clarithromycin is relatively frequent in France and is assumed to be the main cause of failure of the proton pump inhibitor-amoxicillin-clarithromycin (proton pump inhibitor-AC) therapy, which is the first-line regimen in France. AIM: To determine the respective effects of clarithromycin primary and secondary resistances on efficacy of the proton pump inhibitor-AC regimen and to determine whether failures are associated with persistence of the same strain or with emergence of a new one. METHODS: A total of 123 H. pylori-infected patients were treated for 7 days with omeprazole 20 mg b.d., amoxicillin 1 g b.d., and clarithromycin 500 mg b.d. Eradication was assessed by breath test in 102 patients. Minimal inhibitory concentrations of clarithromycin were determined by E-test. Strain genotyping was performed by random amplified polymorphic DNA. RESULTS: The pre-treatment and post-treatment prevalences of clarithromycin resistance were 19% (23 out of 123) and 69% (nine out of 13), respectively. The rates of eradication were 68% (69 out of 102), 79% (67 out of 85), and 12% (two out of 17) for all, susceptible and resistant strains, respectively. The post-treatment isolate was available for six patients with a susceptible pre-treatment isolate and a persistent infection. Resistance emerged in two patients and was associated with persistence of the pre-treatment strain in one and with selection of a new strain in the other. CONCLUSIONS: In our hospital, failures of the proton pump inhibitor-AC therapy are related to both clarithromycin primary and secondary resistances, but the emergence of secondary resistance does not explain all of the failures in the initial clarithromycin-susceptible group. In that group a new strain can emerge after failure.

Administration, Oral↗

Pulmonary scintigraphy for diagnosis of aspiration during intravenous propofol anaesthesia for colonoscopy.

A specific technique for detection of pulmonary aspiration during the perioperative period is lacking. In this study, we developed a scintigraphic method for its diagnosis. Technetium 99m sulphur colloid was given orally 2 h before an i.v. infusion of propofol in patients undergoing elective colonoscopy. During the procedure, patients were spontaneously breathing 100% oxygen via a face mask. After recovery from anaesthesia, patients had a chest scinti-scan. As a control group, 10 healthy men were studied. The lung scan was considered positive if any tracer activity greater than background level was detected in the lung field. Among 96 patients studied, three patients had a positive chest scinti-scan. One of the three patients developed pneumonia while the other two remained asymptomatic. In none of the control asymptomatic group was tracer detected in the chest. We suggest that this technique is specific and can be used as a tool to assess the risk of pulmonary aspiration during different anaesthetic procedures.

Adult↗

Increased intestinal intra-epithelial T lymphocytes in primary glomerulonephritis: a role of oral tolerance breakdown in the pathophysiology of human primary glomerulonephritides?

BACKGROUND: There is increasing evidence that some organ-specific and generalized autoimmune diseases in humans might be related to a breakdown of oral tolerance. We explored this hypothesis in human primary glomerulonephritides. We prospectively counted intraepithelial T lymphocytes in the duodenal mucosa (as a marker of rupture of oral tolerance), together with IgA1 and IgA2 mucosal plasma cells, in patients with primary glomerulonephritides. METHODS: We investigated eight adults with immune-complex glomerulopathy (membranous nephropathy+membranoproliferative glomerulonephritis), 16 adults with an idiopathic nephrotic syndrome, and 25 adults with IgA nephropathy. Patients with glomerulonephritides were compared to two control groups: group 1 consisted of nine healthy adults; group 2 comprised five adults with coeliac disease before dietary gluten withdrawal or during a clinical relapse related to gluten ingestion. (The latter disease is associated with increased numbers of intraepithelial T lymphocytes, and a breakdown of oral tolerance to gliadins is involved in the pathogenesis of coeliac disease). Duodenal fibroscopy was performed under neuroleptanalgesia. Four to six endoscopic biopsy specimens were taken from the second duodenum. Intraepithelial T lymphocytes were blindly counted on paraffin sections stained with haematein-eosin-saffron (HES), within the epithelium of a villus in a zone with at least 100 cells. Mucosal IgA1 and IgA2 plasma cells were blindly counted in a mucosal tissue unit by using specific mouse monoclonal antibodies directed against IgA1 and IgA2, with alkaline phosphatase anti-alkaline phosphatase (APAAP) revelation. As values were not normally distributed, we used non-parametric analysis of variance with the Kruskal-Wallis test, and compared median values by using the non-parametric Mann-Whitney test. RESULTS: Intraepithelial T lymphocytes were significantly more abundant in patients with primary glomerulonephritides and coeliac disease than in healthy controls (P < 0.0001 in the Kruskal-Wallis test): healthy controls, median 11 (range 4.65-16); immune complex glomerulopathy, 27.45*** (15-93); idiopathic nephrotic syndrome, 16.5** (9-26.5); IgA nephropathy, 26.10*** (11.3-47.5); coeliac disease, 55*** (20-80) (*P <0.05; **P <0.01; ***P < 0.005, Mann-Whitney test). No difference was found in the number of duodenal IgA1 and IgA2 plasma cells between controls and patients with primary glomerulonephritides. IgA1 and IgA2 plasma cells were increased in patients with coeliac disease. CONCLUSION: The significant increase in intestinal intraepithelial T lymphocytes in primary glomerulonephritides suggests a pathophysiological role of oral tolerance breakdown.

Antigen-Antibody Complex↗

Helicobacter pylori and gastric lymphoma: high seroprevalence of CagA in diffuse large B-cell lymphoma but not in low-grade lymphoma of mucosa-associated lymphoid tissue type.

OBJECTIVE: Gastric lymphoma of mucosa-associated lymphoid tissue (MALT) type is closely related to Helicobacter pylori (H. pylori) infection. In vitro studies have demonstrated H. pylori-induced B cell proliferation to be strain dependent. High prevalences of CagA protein and FldA protein have been reported in strains obtained from patients with gastric lymphoma of MALT type. The aims of the present study were to evaluate the prevalence of H. pylori infection and to search for antigenic particularities in 53 patients with primary gastric lymphoma in comparison with a group of infected patients with benign disease. METHODS: Of the 53 patients, 37 presented with low-grade lymphoma of MALT type (LGLM) and 16 with diffuse large B-cell lymphoma (DLBCL). They were compared to a group of 162 H. pylori-infected subjects comprising the control group: 111 had gastric or duodenal ulcer (GDU) and 51 nonulcer dyspepsia (NUD). Diagnosis of gastric lymphoma was established on histological examination of endoscopic specimens. Anti-H. pylori antibodies were assayed by third-generation ELISA. Western blot assay was used to detect antibodies against nine antigens (including CagA protein), which were recognized on the basis of their molecular weight. RESULTS: Of the 53 patients with gastric lymphoma, 45 were H. pylori-positive (85%): of these, 25 (56.5%) had anti-CagA antibodies. The prevalence of H. pylori seropositivity was 78% (29/37) in LGLM and 100% (16/16) in DLBCL. The prevalence of CagA seropositivity in H. pylori-positive patients was 44.8% (13/29) and 75% (12/16), respectively (p < 0.05). In comparison, the seroprevalence of CagA was 77.4% (86/111) in GDU patients and 43.1% (22/53) in NUD patients. The prevalence of antibodies to other antigenic proteins detected with Helicoblot 2.0 (19.5kd, 30kd, 35kd, VacA, HSPb, Urease A, and Urease B) did not differ among the groups except for 35kd protein, which was significantly higher (p < 0.01) in GDU than in NUD and in LGLM (76.6% vs 49% and 46.7%). CONCLUSION: These findings suggest that in patients who develop gastric lymphomas in response to H. pylori, virulent strains expressing CagA protein are preferentially associated with DLBCL.

Analysis of Variance↗

[Diagnosis of Helicobacter pylori infection].

Direct or indirect methods are available to diagnose Helicobacter pylori infection. Direct assessment with histopathology, culture, rapide urease test, amplification of gene sequences requires the collection of biopsy samples via an endoscope. Culture is the gold standard, but histopathology is commonly used in clinical practice. Serology, 13C-urea breath test and detection of antigens in stools are indirect methods. In clinical practice, direct assessment is required for the initial diagnosis as only patients with endoscopic lesions need H. pylori eradication. Among indirect methods, serology should be used only in epidemiologic studies. Urea breath test and detection of antigens in stools are the most appropriate methods to assess eradication.

Antigens, Bacterial↗

Cytotoxicity associated with induction of nitric oxide synthase in rat duodenal epithelial cells in vivo by lipopolysaccharide of Helicobacter pylori: inhibition by superoxide dismutase.

The products released by Helicobacter pylori (H. pylori) in the gastric antral and duodenal mucosa may be involved in mucosal ulceration by stimulating the local formation of cytotoxic factors such as nitric oxide (NO), superoxide or peroxynitrite. The present study investigates the ability of purified H. pylori lipopolysaccharide (LPS) to induce nitric oxide synthase (iNOS) in rat duodenal epithelial cells following in vivo challenge and its interaction with superoxide in promoting cellular damage and apoptosis. H. pylori LPS (0.75-3 mg kg(-1) i.v. or 3-12 mg kg(-1) p.o.) induced a dose - dependent expression of iNOS activity after 5 h in the duodenal epithelial cells, determined by [(14)C] arginine conversion to citrulline. The epithelial cell viability, as assessed by Trypan Blue exclusion and MTT conversion, was reduced 5 h after challenge with H. pylori LPS, while the incidence of apoptosis was increased. The iNOS activity and reduction in cell viability following H. pylori LPS challenge i.v. was inhibited by the selective iNOS inhibitor, 1400 W (0.2-5 mg kg(-1) i.v.). Concurrent administration of superoxide dismutase conjugated with polyethylene glycol (250 - 500 i.u. kg(-1), i.v.), which did not modify the cellular iNOS activity, reduced the epithelial cell damage provoked by i.v. H. pylori LPS, and abolished the increased incidence of apoptosis. These results suggest that expression of iNOS following challenge with H. pylori LPS provokes duodenal epithelial cell injury and apoptosis by a process involving superoxide, implicating peroxynitrite involvement. These events may contribute to the pathogenic mechanisms of H. pylori in promoting peptic ulcer disease.

Amidines↗

One-week triple therapy with esomeprazole provides effective eradication of Helicobacter pylori in duodenal ulcer disease.

BACKGROUND: Esomeprazole is the first proton pump inhibitor to be developed as an optical isomer for the treatment of acid-related diseases. METHODS: Four hundred and forty eight duodenal ulcer patients with Helicobacter pylori infection, confirmed by 13C-urea breath test (UBT), and no current ulcer, were randomised to double-blind treatment with esomeprazole 20 mg twice daily (b.d.) (n=224) or omeprazole 20 mg b.d. (n=224), in combination with amoxicillin 1 g b.d. and clarithromycin 500 mg b.d. for 1 week (EAC and OAC, respectively). A negative UBT at both 4 and 8 weeks after completing therapy indicated successful H. pylori eradication. RESULTS: Intention-to-treat (ITT) analysis comprised 400 patients (EAC, n=204; OAC, n=196) and per protocol (PP) analysis 377 patients (EAC, n=192; OAC, n=185). Eradication rates (95% confidence intervals) for ITT and PP populations were: EAC, 90% (85-94%) and 91% (86-94%); OAC, 88% (82-92%) and 91% (86-95%). Between-group differences in eradication rates were not statistically significant. Both regimens were well tolerated, with an adverse event profile and frequency typical of proton pump inhibitor plus antibiotic combination therapy. CONCLUSIONS: Esomeprazole-based triple therapy for 1 week is highly effective in eradicating H. pylori infection in duodenal ulcer disease, offers comparable efficacy to omeprazole-based therapy, and is well tolerated.

Adult↗

The HOMER Study: the effect of increasing the dose of metronidazole when given with omeprazole and amoxicillin to cure Helicobacter pylori infection.

BACKGROUND: Helicobacter pylori eradication with omeprazole, amoxycillin, and metronidazole is both effective and inexpensive. However, eradication rates with different dosages and dosing vary, and data on the impact of resistance are sparse. In this study, three different dosages of omeprazole, amoxycillin, and metronidazole were compared, and the influence of metronidazole resistance on eradication was assessed. METHODS: Patients (n = 394) with a positive H. pylori screening test result and endoscopy-proven duodenal ulcer in the past were enrolled into a multicenter study performed in four European countries and Canada. After baseline endoscopy, patients were randomly assigned to treatment for 1 week with either omeprazole, 20 mg twice daily, plus amoxycillin, 1,000 mg twice daily, plus metronidazole, 400 mg twice daily (low M); or omeprazole, 40 mg once daily, plus amoxycillin, 500 mg three times daily, plus metronidazole, 400 mg three times daily (medium M); or omeprazole, 20 mg twice daily, plus amoxycillin, 1,000 mg twice daily, plus metronidazole, 800 mg twice daily (high M). H. pylori status at entry was assessed by a 13C urea breath test and a culture. Eradication was defined as two negative 13C-urea breath test results 4 and 8 weeks after therapy. Susceptibility testing using the agar dilution method was performed at entry and in patients with persistent infection after therapy. RESULTS: The eradication rates, in terms of intention to treat (ITT) (population n = 379) (and 95% confidence interval [CI]) were as follows: low M 76% (68%, 84%), medium M 76% (68%, 84%), and high M 83% (75%, 89%). By per-protocol analysis (population n = 348), the corresponding eradication rates were: low M 81%, medium M 80%, and high M 85%. No H. pylori strains were found to be resistant to amoxycillin. Prestudy resistance of H. pylori strains to metronidazole was found in 72 of 348 (21%) of the cultures at entry (range, 10%-39% in the five countries). The overall eradication rate in prestudy metronidazole-susceptible strains was 232 of 266 (87%) and, for resistant strains, it was 41 of 70 (57%; p <.001). Within each group, the results were as follows (susceptible/resistant): low M, 85%/54%; medium M, 86%/50%; and high M, 90%/75%. There were no statistically significant differences among the treatment groups. 23 strains susceptible to metronidazole before treatment were recultured after therapy failed; 20 of these had now developed resistance. CONCLUSIONS: H. pylori eradication rates were similar (approximately 80%) with all three regimens. Metronidazole resistance reduced efficacy; increasing the dose of metronidazole appeared not to overcome the problem or significantly improve the outcome. Treatment failure was generally associated with either prestudy or acquired metronidazole resistance. These findings are of importance when attempting H. pylori eradication in communities with high levels of metronidazole resistance.

Adolescent↗

Rabeprazole, 20 mg once daily or 10 mg twice daily, is equivalent to omeprazole, 20 mg once daily, in the healing of erosive gastrooesophageal reflux disease.

BACKGROUND: Proton pump inhibitors are the most potent pharmacologic inhibitors of gastric acid secretion currently available, and have proven effective in the treatment of gastro-oesophageal reflux disease (GERD). The object of this study was to compare the efficacy and tolerability of a new proton pump inhibitor, rabeprazole at two different dosages, with that of omeprazole in the healing of erosive GERD. METHODS: Rabeprazole 20 mg once daily (QD) and 10 mg twice daily (BID) were compared with omeprazole 20 mg QD in a double-blind, multicentre, parallel group study involving 310 patients with erosive GERD. The primary efficacy endpoint was oesophageal mucosal healing determined by endoscopy. Secondary endpoints included reduction in symptoms and improvements in quality-of-life scores. RESULTS: The healing rates between both rabeprazole groups and the omeprazole group were equivalent in both the per-protocol and intent-to-treat populations. In the per-protocol population, rabeprazole 20 mg was noted to have a numerical trend toward more rapid daytime heartburn relief. However, by 4 and 8 weeks of treatment, no significant differences were found between groups for secondary endpoints, adverse events, or laboratory abnormalities including elevation of serum gastrin levels. CONCLUSIONS: Rabeprazole 20 mg in two different dosing schedules is as effective as omeprazole 20 mg QD with regard to efficacy and tolerability in patients with erosive GERD.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Duodenal mucosa-associated lymphoid tissue lymphoma: treatment with oral cyclophosphamide.

Small cell mucosa-associated lymphoid tissue (MALT) lymphomas rarely affect the duodenum, and optimal treatment has not been defined. The aim of this case series was to determine the clinical features and outcome of duodenal MALT lymphoma in four patients (three men, one woman; median age 52 yr) treated with cyclophosphamide p.o. Initial manifestations were abdominal pain (n = 4), vomiting (n = 2), and an obstructive syndrome (n = 1). MALT lymphoma was diagnosed on the basis of endoscopic biopsies. It was localized in the duodenum in three cases and involved the entire small bowel in one case. Tumor infiltration was limited to the duodenal wall in one case and was associated with locoregional lymphadenopathy in three cases. The patients were graded EI (n = 1) and EII1 (n = 3), respectively, according to the Ann Arbor classification revised by Musshof. Cyclophosphamide, 100 mg daily, was administered p.o. for 18 months. Gastroscopy with biopsies, radiography of the small intestine and abdominal CT (CT) were performed every 6 months. Complete remission was defined by morphological and histological normalization, and partial remission as morphological normalization only. Follow-up lasted from 9 to 65 months. Three patients were in complete remission at 18 months: two relapsed after 2 yr and one was still in complete remission at 65 months. The patient with 9 months of follow-up was in complete remission at 6 months. The two patients who relapsed did not complain of symptoms, and no morphological abnormalities were seen. Relapse was diagnosed on histological grounds. Cyclophosphamide monotherapy p.o. thus seems well adapted to this slowly progressive disease, but it is unclear whether it should be resumed in the case of histological relapse or only in the case of symptomatic relapse. (Am J Gastroenterol 2000;95:536-539. (O 2000 by Am. Coll. of Gastroenterology)

Administration, Oral↗

Frequent association between alteration of the rdxA gene and metronidazole resistance in French and North African isolates of Helicobacter pylori.

Mutations in the rdxA gene have been associated with the acquisition of resistance to metronidazole in Helicobacter pylori. This gene encodes an NADPH nitroreductase whose expression is necessary for intracellular activation of the drug. We wished to examine whether mutations in rdxA were present in resistant H. pylori isolates infecting either French or North African patients. We determined the complete nucleotide sequences of the rdxA genes from seven French and six North African patients infected with paired resistant and sensitive strains. Genotyping by random amplified polymorphic DNA analysis confirmed the close genetic relatedness of the susceptible and resistant isolates from individual biopsies. Eight French and five North African individual resistant strains were also studied. For the French strains, an alteration in rdxA most probably implicated in resistance was found in 10 cases (seven frameshift mutations, two missense mutations, and one deletion of 211 bp). One to three putative missense mutations were identified in four cases, and a missense mutation possibly not implicated in resistance was discovered in the last case. For the North African strains, an alteration in rdxA was found in eight cases (three frameshift mutations, three missense mutations, one deletion of 6 bp, and one insertion of a variant of IS605). Two strains contained putative missense mutations, and no change was observed in rdxA of the last strain. Thus, inactivation of the rdxA gene is frequently, but not always, associated with resistance to metronidazole in French and North African clinical isolates of H. pylori. In addition, a variety of alterations of rdxA are associated with the resistant phenotype.

Africa, Northern↗

[Small bowel pseudo-obstruction revealing an early scleroderma. Long-term efficacy of octreotide and erythromycin].

Skin abnormalities are the most common manifestations in patients with systemic sclerosis but many other organs can be involved. We report here the case of a 61 year-old-man in whom small bowel involvement was the initial presentation of limited systemic sclerosis. The clinical features consisted of recurrent small bowel obstruction without any organic lesion. The patient responded well to erythromycin (125 mg thrice a day before meals) and octreotide (50 microg subcutaneously at bedtime) with complete symptom relief. This permitted recovery of nutritional autonomy for two years. This observation shows that, in patients with intestinal pseudo-obstruction, systemic sclerosis should be considered. The long-term administration of octreotide and erythromycin can be effective in treating small bowel dysmotility in such patients.

Antibodies, Antinuclear↗

Oral Crohn disease: clinical characteristics and long-term follow-up of 9 cases.

BACKGROUND: Oral localization of Crohn disease is uncommon and must be differentiated from nonspecific lesions. Its natural course and its long-term prognosis are unknown. OBSERVATIONS: We studied 9 patients (8 male, 1 female; age range, 7-52 years; median age, 16 years) with Crohn disease and specific oral lesions, including deep linear ulcers, pseudopolyps, and/or labial or buccal swelling and induration. The prevalence of such lesions was 0.5%. The median follow-up was 11 years. Oral localization developed before (n = 2), at the same time as (n = 2), or after (n = 5) the onset of the digestive disease. Noticeable associated localizations were observed in the anoperineum (n = 8) and the esophagus (n = 3). The median duration of the oral lesions was 4 years (range, 1-13 years), without necessary parallelism with the digestive localization. Five patients had complete healing after a median delay of 2 years. CONCLUSIONS: Oral localization of Crohn disease is characterized by a marked male predominance, a young age at onset of Crohn disease, and a very protracted course. The high prevalence of associated anal and esophageal involvement suggests that Crohn lesions have a particular trophicity for squamous cell epithelium.

Adolescent↗

Seroprevalence of eight Helicobacter pylori antigens among 182 patients with peptic ulcer, MALT gastric lymphoma or non-ulcer dyspepsia. Higher rate of seroreactivity against CagA and 35-kDa antigens in patients with peptic ulcer originating from Europe and Africa.

BACKGROUND: It has been suggested that Helicobacter pylori may induce more or less severe gastroduodenal disease according to the strain virulence. DESIGN: We used Western blot to determine antigenic profiles associated with duodenal or gastric ulcer disease, MALT lymphoma and non-ulcer dyspepsia, and to identify geographical differences. METHODS: One hundred and eighty-two consecutive patients with H. pylori infection were studied. H. pylori infection was diagnosed by a rapid urease test or histological examination of gastric biopsy samples. Bacterial density and gastritis were assessed histologically by using the Sydney scoring system. Western blot was used to identify antibodies against eight antigens (CagA, VacA, urease A, heat shock protein B, and 19.5, 26.5, 30 and 35 kDa). Patients were questioned on their smoking habits and place of birth and childhood. RESULTS: There were 73 patients with duodenal ulcer, 30 with gastric ulcer, eight with erosive duodenitis, 17 with gastric MALT lymphoma and 54 with non-ulcer dyspepsia. Most (>85%) were seropositive for the heat shock protein B and 26.5-kDa antigens. The prevalence of the other antigens ranged from 45% (VacA) to 68% (urease B). The seroprevalence of CagA antigen was significantly higher (P < 0.01) in cases of gastroduodenal ulcer (84%) than non-ulcer dyspepsia (37%). Similarly, 35-kDa antigen reactivity was more frequent (P < 0.05) in duodenal ulcer patients (75%) than in those with non-ulcer dyspepsia (50%). The antigenic profiles associated with MALT gastric lymphoma and non-ulcer dyspepsia were similar. Multivariate analysis showed that only gastroduodenal ulcer was significantly associated with CagA. Gastroduodenal ulcer and a childhood spent in Africa were both associated with 35-kDa and combined CagA-35-kDa reactivity. CONCLUSIONS: This study confirms the strong seroprevalence of H. pylori CagA antigen and shows a high prevalence of the 35-kDa antigen in patients with gastroduodenal ulcer, especially those raised in Africa. There was no difference in the serological pattern between patients with non-ulcer dyspepsia and those with MALT lymphoma. Tests for antibodies to the CagA-35-kDa antigen combination might be used to select H. pylori-infected dyspeptic patients warranting treatment.

Africa↗

Omeprazole, amoxycillin and metronidazole for the cure of Helicobacter pylori infection.

OBJECTIVE: In two studies, different regimens of omeprazole-amoxycillin-metronidazole were assessed for the eradication of Helicobacter pylori. DESIGN: Randomized, international, multicentre studies with parallel groups. SETTING: The studies were performed at centres in Canada, Czech Republic, France, Germany, Hungary, Sweden and UK. PARTICIPANTS AND INTERVENTIONS: H. pylori-positive patients with duodenal ulcer disease (active or in remission) were randomized to 7-day treatment with: omeprazole 40 mg once daily, amoxycillin 500 mg three times daily and metronidazole 400 mg three times daily (OAMtid; n = 242); omeprazole 20 mg twice daily, amoxycillin 1000 mg twice daily and metronidazole 800 mg twice daily (OAM800; n = 247); or omeprazole 20 mg twice daily, amoxycillin 1000 mg twice daily and metronidazole 400 mg twice daily (OAM400; n = 127). MAIN OUTCOME MEASURES: Eradication of H. pylori. RESULTS: Intention-to-treat analysis revealed H. pylori eradication rates of 76% (184/242) with OAMtid, 80% (198/247) with OAM800, and 76% (97/127) with OAM400. There was considerable variation in the levels of primary resistance to metronidazole in different countries. The overall eradication rate in patients infected with metronidazole-sensitive H. pylori strains was 85% (313/370), compared with 60% (56/94) in patients harbouring metronidazole-resistant strains (P<0.001). All regimens were generally well tolerated, with mild adverse events occurring in 4-26% of patients (mainly diarrhoea, reversible increase in liver enzymes and headache). CONCLUSION: The OAM combination is effective in curing H. pylori infection. Primary metronidazole resistance may reduce its effectiveness, but an increased daily dosing of metronidazole may partly overcome this problem.

Amoxicillin↗

Serum antibody responses to Helicobacter pylori and the cagA marker in patients with mucosa-associated lymphoid tissue lymphoma.

The lymphoma of the mucosa-associated lymphoid tissue (MALT) of the stomach has been linked to Helicobacter pylori infection, but the mechanisms involved in B-cell proliferation remain elusive. In a search for putative H. pylori-specific monoclonal immunoglobulin production, an H. pylori strain was isolated from 10 patients with MALT lymphoma and used to detect the specific serum antibody response to the homologous strain by immunoblotting. Moreover, the antigenicity of the different strains was compared by using each of the 10 sera. We found that the different strains induced highly variable patterns of systemic immunoglobulin G antibody response, although several bacterial antigens, such as the 60-kDa urease B, were often recognized by the different sera. The cagA marker was detected in the strains by PCR with specific primers and by dot blot analysis, and the CagA protein was found in the sera of 4 of the 10 patients by immunoblotting. In conclusion, MALT lymphoma patients, like other patients with H. pylori gastritis, exhibit a polymorphic systemic antibody response, despite an apparently similar antigenic profile. The CagA marker of pathogenicity is not associated with this disease.

Antibodies, Bacterial↗