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S Vigneri

Publications and source records attributed to S Vigneri.

At least 37 records · Page 2Linked to original sources
PubMed2000

The impact of antibiotic resistance on the efficacy of three 7-day regimens against Helicobacter pylori.

BACKGROUND: Antibiotic resistance affects the success of anti-Helicobacter pylori therapies and varies greatly from country to country. AIM: To compare the efficacy of three short-term triple regimens in relation to H. pylori primary resistance in our region. METHODS: We enrolled 210 H. pylori-positive dyspeptic patients for this randomized, open, parallel-group study. Three arms of 70 patients each received the following 1-week regimens: (1) ranitidine bismuth citrate 400 mg b.d. + clarithromycin 250 mg b.d. + metronidazole 500 mg b.d. (RCM); (2) bismuth subcitrate 240 mg b.d. + amoxycillin 1000 mg b.d. + metronidazole 500 mg b.d. (BAM); (3) omeprazole 20 mg o.d. + clarithromycin 250 mg b.d. + metronidazole 500 mg b.d. (OCM). H. pylori was assessed by CLO-test and histology before and 4 weeks after therapy. Antibiotic resistance was assessed by E-test. RESULTS: On intention-to-treat analysis RCM was more effective than OCM (84% vs. 69%; P < 0.03) and BAM (84% vs. 63%; P < 0.004). MIC determination was successful in 117 out of 210 patients (55%); metronidazole resistance was present in 52 out of 117 patients (44%) and clarithromycin resistance was present in 17 out of 117 patients (14%). Excellent cure rates were achieved when strains were sensitive to both antibiotics (100% with RCM and BAM and 90% with OCM), whereas RCM was superior to OCM (P=0.009) and BAM (P=0.001) with respect to overall resistant strains (94% vs. 57% and 38%, respectively). CONCLUSIONS: One-week RCM is the best regimen to eradicate H. pylori in our geographical area. This seems to be linked to the better ability of RCM compared to OCM and BAM in overcoming the high prevalence of H. pylori resistance to both metronidazole and clarithromycin in our region.

Adult↗
PubMed2000

Fluvastatin reduces soluble P-selectin and ICAM-1 levels in hypercholesterolemic patients: role of nitric oxide.

BACKGROUND: Lipid-lowering therapy with 3-hydroxy-3-methylglutaryl-coenzymeA (HMG-CoA) reductase inhibitors reduces the incidence of atherosclerosis-related cardiovascular events. Adhesion molecules, regulating interactions between vascular and circulating cells, may play a central role in the pathogenesis of atherosclerosis and related complications. In the present report we examined the impact of the HMG-CoA reductase inhibitor fluvastatin on plasma levels of P-selectin and ICAM-1. METHODS: Plasma levels of P-selectin and ICAM-1 were determined using an enzyme immunoassay in 26 patients with type IIa hypercholesterolemia randomized to treatment with either fluvastatin (80 mg/d) or placebo in a double blind fashion for 12 weeks. RESULTS: Fluvastatin administration reduced either P-selectin (118 +/- 63 vs 81 +/- 36 ng/mL [-31%], P = 0.0015) or ICAM-1 (264 +/- 75 vs 228 +/- 68 ng/mL [-13.7%], P = 0.0033) levels. Fluvastatin also lowered urinary 11-dehydro-TXB2 (1396 +/- 536 vs 1009 +/- 378 pg/mg creatinine [-27%], P = 0.0015) and von Willebrand Factor levels (1456 +/- 716 vs 1203 +/- 527 U/L [-17.4%], P = 0.0275), and a direct correlation was observed between P-selectin and 11-dehydro-TXB2 levels (r = 0.588, P = 0.0033). Patients treated with fluvastatin displayed an increase in nitric oxide (NO) generation, evaluated with measurements of serum NO2-/NO3-, (4.7 +/- 1 vs 8.9 +/- 3.1) mumol/L [98%], P = 0.0046). Moreover, an inverse correlation was observed between NO2-/NO3- and P-selectin (r = -0.420; P = 0.0343), 11-dehydro-TXB2 (r = -0.511; P = 0.0106), or LDL (r = -0.742; P = 0.0002) levels. CONCLUSIONS: These results may provide novel biochemical basis for the beneficial clinical effects of HMG-CoA reductase inhibitors in hypercholesterolemia.

Adult↗
PubMed1999

Optimal duration of therapy combining ranitidine bismuth citrate with clarithromycin and metronidazole in the eradication of Helicobacter pylori infection.

BACKGROUND: Ranitidine bismuth citrate (RBC) co-prescribed with clarithromycin and metronidazole for 1 week has been shown to be an effective eradicating regimen for Helicobacter pylori. AIM: To determine the optimal duration of this regimen. METHODS: A series of 165 dyspeptic patients were recruited for this randomized, open, parallel-group study. They were subdivided into three groups receiving RBC 400 mg b.d. plus clarithromycin 250 mg b.d. and metronidazole 500 mg b.d. for three different periods (4, 7 and 10 days). H. pylori infection was assessed by the concomitant positivity of CLO-test and histology performed at the pre-entry endoscopy. The bacterium was considered eradicated on the basis of a negative 13C-urea breath test performed at least 28 days after the completion of treatment. RESULTS: The three subgroups were well matched and 16 patients dropped out of the study for many reasons (six in the 4-day, five in the 7-day and five in the 10-day treatment regimens). Intention-to-treat cure rates were 60%, 84% and 85%, and the per-protocol rates 67%, 92% and 94% in the 4-day, 7-day and 10-day treatment regimens, respectively. There was a significant difference, P = 0.003-0.006 on intention-to-treat and P = 0.001-0. 002 on per protocol analysis between the 4-day and the 7-day and the 4-day and the 10-day periods, respectively. The 7-day and 10-day periods did not differ from each other. Side-effects were reported in 9%, 14% and 20% of the 4-, 7- and 10-day regimens. They led to stopping treatment in four cases (one in the 7-day and three in the 10-day period). There was no statistical difference among them. CONCLUSIONS: Reducing the duration of RBC-based triple therapy to 4 days provides a low and unacceptable rate of H. pylori eradication. As there is no difference between 7 and 10 days of treatment, 1 week represents the optimal time period for this kind of treatment, based on RBC plus two antibiotics.

Anti-Bacterial Agents↗
PubMed1999

Head-to-head comparison of 1-week triple regimens combining ranitidine or omeprazole with two antibiotics to eradicate Helicobacter pylori.

BACKGROUND: Triple therapies containing omeprazole and ranitidine have been shown to be equivalent in eradicating H. pylori infection, but have been assessed either separately or head-to-head, only in small trials. AIM: To carry out a large randomized controlled study comparing omeprazole and ranitidine combined with two antibiotic combinations for 1 week. METHODS: Three hundred and twenty H. pylori-positive patients were randomly subdivided into four equal-sized groups and received one of the following treatments: OAM = omeprazole 20 mg b.d. + amoxycillin 1 g b.d. + metronidazole 500 mg b.d.; RAM = ranitidine 300 mg b.d. + amoxycillin 1 g b.d. + metronidazole 500 mg b.d.; OAC = omeprazole 20 mg b.d. + amoxycillin 1 g b.d. + clarithromycin 250 mg t.d.s.; RAC = ranitidine 300 mg b.d. + amoxycillin 1 g b.d. + clarithromycin 250 mg t.d.s. The assessment of H. pylori status was performed before and 4 weeks after the end of therapy by means of CLO-test and histology. H. pylori infection was considered to be eradicated when both tests were negative. RESULTS: OAM and RAM eradicated H. pylori in 89% and 85% of cases on per protocol (P = 0.48) and in 77% and 75% of cases on intention-to-treat analyses (P = 0.71). OAC and RAC eradicated H. pylori in 67% and 70% of cases on per protocol (P = 0.68) and in 57% and 64% of cases on intention-to-treat analyses (P = 0.41). In contrast, there was significant difference between OAM and OAC (P<0.01) and between RAM and RAC (P<0.05). Side-effects occurred in 15%, 10%, 17% and 16% of patients with respect to the above four subgroups. CONCLUSIONS: Omeprazole and ranitidine combined with two antibiotics for 1 week are equally effective in the eradication of H. pylori infection, and these results question the role of profound acid suppression in the eradication of the bacterium.

Adult↗
PubMed1999

Comparison of isotope ratio mass spectrometry and nondispersive isotope-selective infrared spectroscopy for 13C-urea breath test.

OBJECTIVES: The 13C-urea breath test (UBT) is a sensitive and noninvasive method to diagnose Helicobacter pylori infection, but mass spectrometry (IRMS) is very expensive. The aims of this study were to compare the new low-priced infrared spectroscopy with IRMS in detecting the infection and to assess the influence of feeding on test accuracy. METHODS: One hundred thirty-four patients with dyspeptic symptoms were recruited. Of these, 74 were infected and 60 uninfected on the basis of both CLO-test and histology. A subgroup of 37 patients (22 H. pylori-positive and 15 H. pylori-negative) was studied under fasting and nonfasting conditions on two different days. Duplicate breath samples were analyzed with two IRMS systems (Breath Mat and ABCA) and an infrared spectrometer (IRIS) before, 15 min, and 30 min after ingestion of 75 mg 13C-urea with citric acid. In 37 patients the test was repeated the day after the fasted one and was performed 60 min after a meal of 800 Kcal. RESULTS: There was a close correlation between IRIS and Breath Mat (r = 0.969 at 15 min and r = 0.977 at 30 min; p < 0.0001), IRIS and ABCA (r = 0.963 at 15 min and r = 0.985 at 30 min; p < 0.0001), and Breath Mat and ABCA (r = 0.987 at 15 min and r = 0.981 at 30 min; p = 0.0001). The sensitivity ranged from 97-100% at both times with all devices, although the specificity was slightly inferior with the infrared system than with the two IRMS machines (95% vs 98-100% at 30 min), but the difference was not significant (p = NS). Food intake produced three false negative results in all three machines and a systematic shift to lower 6 values in infected patients. CONCLUSIONS: Infrared spectroscopy can be considered a valid alternative to mass spectroscopy for the diagnosis of H. pylori infection. Fasting is required to guarantee an accurate test.

Breath Tests↗
PubMed1999

The 13C urea breath test in the diagnosis of Helicobacter pylori infection.

The urea breath test (UBT) is one of the most important non-invasive methods for detecting Helicobacter pylori infection. The test exploits the hydrolysis of orally administered urea by the enzyme urease, which H pylori produces in large quantities. Urea is hydrolysed to ammonia and carbon dioxide, which diffuses into the blood and is excreted by the lungs. Isotopically labelled CO2 can be detected in breath using various methods. Labelling urea with 13C is becoming increasingly popular because this non-radioactive isotope is innocuous and can be safely used in children and women of childbearing age. Breath samples can also be sent by post or courier to remote analysis centres. The test is easy to perform and can be repeated as often as required in the same patient. A meal must be given to increase the contact time between the tracer and the H pylori urease inside the stomach. The test has been simplified to the point that two breath samples collected before and 30 minutes after the ingestion of urea in a liquid form suffice to provide reliable diagnostic information. The cost of producing 13C-urea is high, but it may be possible to reduce the dosage further by administering it in capsule form. An isotope ratio mass spectrometer (IRMS) is generally used to measure 13C enrichment in breath samples, but this machine is expensive. In order to reduce this cost, new and cheaper equipment based on non-dispersive, isotope selective, infrared spectroscopy (NDIRS) and laser assisted ratio analysis (LARA) have recently been developed. These are valid alternatives to IRMS although they cannot process the same large number of breath samples simultaneously. These promising advances will certainly promote the wider use of the 13C-UBT, which is especially useful for epidemiological studies in children and adults, for screening patients before endoscopy, and for assessing the efficacy of eradication regimens.

Breath Tests↗
PubMed1998

Comparison of 24-h control of gastric acidity by three different dosages of pantoprazole in patients with duodenal ulcer.

BACKGROUND: It is now clear that the extent to which gastric acid secretion must be suppressed varies with the clinical condition being treated. AIM: To assess the 24-h control of gastric acidity and the individual response variability of three different doses of pantoprazole. METHODS: Sixty-four duodenal ulcer patients were recruited for this prospective, randomized, multicentre, double-blind, parallel-group study. They were subdivided into three well-matched groups treated with 20 mg o.m., 40 mg o.m. and 40 mg b.d. of pantoprazole, respectively. Endoscopy and intragastric pH monitoring were performed in each patient before and after 14 days of treatment. RESULTS: Fifty-five patients were eligible for final analysis (17 treated with 20 mg o.m., 18 with 40 mg o.m. and 20 with 40 mg b.d. pantoprazole). The ulcer crater healed in 94, 88 and 95% of cases, respectively. The three dosages of pantoprazole produced significant increases in gastric pH compared to basal levels (P < 0.0001). There was also a clear dose-dependent pharmacodynamic effect, which augmented on moving from the lowest dosage of 20 mg o.m. pantoprazole to the highest dosage of 40 mg b.d. (P < 0.01-0.001). The inter-individual response variability within the three treatment groups was more marked with the dose of 20 mg than with the two higher doses of pantoprazole. CONCLUSIONS: All three doses of pantoprazole we tested are highly effective in decreasing gastric acidity and there is a clear dose-dependent pharmacodynamic effect on moving from the lowest to the highest dosage. The greatest inter individual variation in the degree of acid inhibition was seen with pantoprazole 20 mg o.m., while the majority of patients responded adequately to the two higher doses of the drug.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1998

Optimal PPI-based triple therapy for the cure of Helicobacter pylori infection: a single center comparison of four 14-day schedules.

BACKGROUND: Helicobacter pylori eradication is accomplished using a wide array of drugs combined in a multitude of dosage schedules. The aim of the present study was to define the best 14-day eradication schedule using a PPI plus either two antibiotics or one antibiotic and bismuth. MATERIAL AND METHODS: For this study, 367 subjects (198 males, 169 females, age 22-87 years) with document H. pylori infection of the stomach were recruited from out-patients of the Gastroenterology Department of the Venezia Hospital. In all patients, H. pylori infection was identified by histology and the CLO-test. Patients were treated as follows: 1) PPI (P) plus clarithromycin (C) 250 mg plus amoxicillin (A) 1000 mg bid (P + C + A); 2) P plus C plus bismuth subcitrate (B) 120 mg qid (P + C + B); 3) P plus C plus tinidazole (T) 500 mg bid (P + C + T); and 4) P plus A plus T bid (P + A + T). After two months, an upper gastrointestinal endoscopy was repeated for end point histological evaluation and the CLO- test. Positivity of one of the two methods was considered sufficient to define H. pylori as "not eradicated". STATISTICS: Chi-squared test and Fisher exact test. RESULTS: Thirty-three subjects dropped out (six due to adverse events). P + C + B was proven significantly less effective than P + C + A, P + C + T and P + A + T, eradication rates being, respectively, 75.0%, 90.5%, 87.6%, 92.0%, (p = .005, per protocol analysis). CONCLUSIONS: All PPI-based triple therapies tested in this study were effective in curing H. pylori infection; however, P + C + B resulted in rates too low (< 85%) to be recommended. P + C + A and P + A + T resulted in the high cure rates and thus may be considered the treatment of choice.

Adult↗
PubMed1998

Low dose of clarithromycin in triple therapy for the eradication of Helicobacter pylori: one or two weeks?

The aims of this pilot study were: (i) to compare the efficacy of low-dose clarithromycin (250 mg twice daily) for 1 or 2 weeks; and (ii) to evaluate possible therapeutic advantages in associating the low-dose clarithromycin with an anti-secretory agent or tripotassium dicitrate bismuthate (De Nol; Yamanouchi Pharm, Corugate Milano, Italy). A prospective, randomized, open trial was carried out on consecutive outpatients with dyspeptic symptoms and Helicobacter pylori infection. We enrolled 129 patients in one of the following schedules: (A) De Nol 120 mg q.i.d., clarithromycin 250 mg b.i.d. and metronidazole 250 mg q.i.d. for 2 weeks; (B) omeprazole 20 mg b.i.d., clarithromycin 250 mg b.i.d. and metronidazole 250 mg q.i.d. for 2 weeks; or (C) omeprazole 20 mg b.i.d., clarithromycin 250 mg b.i.d. and metronidazole 250 mg q.i.d. for 1 week. Results were evaluated by Per Protocol (PP) and Intention-To-Treat analysis (ITT). Eradication rate was 100% after treatment A, 92.6% after treatment B and 86.5% after treatment C by PP and 83.3, 75.7, and 68.1%, respectively by ITT. Side effects were reported by 16 subjects: 26.6% in group A; 9.1% in group B; and 7.5% in group C; in two cases side effects led to the withdrawal of the treatment. In conclusion, 500 mg clarithromycin per day in association with omeprazole and metronidazole, for 1 week gave comparable results to the same schedule for a 2 week period. The use of clarithromycin with bismuth and metronidazole produced a therapeutic gain compared with both of the anti-secretory schedules, although this was not statistically significant.

Adult↗
PubMed1998

Strategy for the retreatment of failed Helicobacter pylori eradication therapy: a case series.

BACKGROUND: Helicobacter pylori eradication therapy can be unsuccessful in 5 to 20% of patients. AIM: To investigate the validity of a strategy using triple therapies for the retreatment of patients with eradication failure, avoiding retreatment with antibiotics prone to induce resistance after use in the first treatment. PATIENTS AND METHODS: From a consecutive sampling of 108 patients still Helicobacter pylori-positive after a first course of antibiotic-based treatment, 74 (68.5%) agreed to a second course of triple therapy. Group 1 (N = 17): treatment failures on an imidazole (1)-based therapy were retreated with clarithromycin (C)-based regimen; Group 2 (N = 28): failures on a C-based therapy with an I-based regimen; Group 3 (N = 7): failures on an IC-based therapy using an I-based regimen and Group 4 (N = 22): failures on a non-I/non-C based therapy with either an I-based, C-based or IC-based regimen. The presence of Helicobacter pylori was assessed by histology and the CLO-test at study entry and two months after stopping therapy. RESULTS: Nine patients were withdrawn from the study (12.2%) due to a lack of end point endoscopy. Helicobacter pylori was cured after the second course of therapy in all but seven patients [10.7% failure by Per Protocol analysis, 21.6% by Intention-To-Treat analysis]. No statistically significant differences were found between the four groups (Group 1: 92.9% PP, 76.5% ITT; Group 2: 90.9% PP, 71.4% ITT; Group 3: PP and ITT 85.7%; Group 4: PP and ITT 86.4%). Minor adverse events were experienced in nine, none of whom required withdrawal from the drug therapy. CONCLUSIONS: A second course of triple therapy with alternate antibiotics effectively eradicated Helicobacter pylori, with only very few treatment failures. This suggests that the therapeutic strategy employed may be recommended.

Adult↗
PubMed1997

24-hour gastric pH and extent of duodenal gastric metaplasia in Helicobacter pylori-positive patients.

BACKGROUND & AIMS: Gastric metaplasia (GM) is essential to explain duodenal colonization by Helicobacter pylori. It seems to be acid induced but also occurs in H. pylori-positive patients with nonulcer dyspepsia (NUD), who are not acid hypersecretors. The aim of this study was to assess the circadian gastric acidity of 47 patients with duodenal ulcers (DUs) and 32 patients with NUD, both H. pylori positive, and its correlation to duodenal GM extent. METHODS: H. pylori was detected by histology and CLOtest, and GM was diagnosed and graded on four bulb biopsy specimens. Each patient underwent 24-hour gastric pH-metry, and the relation between gastric pH and GM extent was assessed by factorial analysis. RESULTS: Gastric pH was greater in patients with NUD than in patients with DU during 24 hours, night and daytime (P < 0.03-0.005). Gastric pH differed significantly (P < 0.0002) in relation to GM extent between the two populations, whereas no difference was found among the pH values of GM degrees. A significant increase in 24-hour gastric pH was associated with greater GM in patients with DU, whereas the opposite occurred in patients with NUD (P < 0.007). CONCLUSIONS: The lower gastric acidity in patients with NUD than in patients with DU and the lack of correlation between gastric pH and the various GM degrees in the two H. pylori-positive populations suggest that gastric hyperacidity is not associated with duodenal GM.

Adult↗