Panel discussion - unresolved issues
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to F Bazzoli.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
BACKGROUND: The potential influence of cognitive status, physical activities, comorbidity and cotreatments on the feasibility and diagnostic accuracy of two noninvasive diagnostic tests for Helicobacter pylori (Hp) infection, i.e., the 13C-urea breath test (13C-UBT) and serology (immunoglobulin G [IgG] anti-Hp antibodies), in older subjects is not known. METHOD: The study involved 100 consecutive symptomatic elderly subjects (mean age, 78.3 years; range, 65-96 years), who had undergone an upper gastrointestinal endoscopy. Patients were considered Hp positive if at least two of the three invasive methods, i.e. histology, culture, and/or the rapid urease test were positive for Hp infection. Patients were considered Hp negative if all three invasive methods were negative. The 13C-UBT was performed according to the European standard method and the assaying of IgG anti-Hp antibodies by enzyme-linked immunosorbent assay. Cognitive status and functional activities were determined by the Mini-Mental State Examination (MMSE), the activities of daily living (ADLs) and instrumental ADLs (IADLs). RESULTS: According to invasive methods, 49 patients were Hp positive and 47 were Hp negative (4 subjects were excluded from the study). Hp-positive patients demonstrated a significantly higher prevalence of peptic ulcers (p =.02) and activity of chronic gastritis (p<.0001) than Hp-negative subjects. The 13C-UBT demonstrated a sensitivity of 100%, a specificity of 95.7%, and a diagnostic accuracy of 97.9%. Serology had significantly lower sensitivity (74.4%), specificity (59%), and diagnostic accuracy (67%, p<.001) than the 13C-UBT. The feasibility and the diagnostic accuracy of the 13C-UBT were not altered by the cognitive status (MMSE) and functional activities (ADL, IADL) of the patients, their drug consumption, or the prevalence of concomitant diseases. CONCLUSIONS: In older subjects, the 13C-UBT had a significantly higher diagnostic accuracy than serology without influence of cognitive function, disability, comorbidity and cotreatments. This method may be considered an excellent, clinically useful, noninvasive test for the diagnosis of Hp infection in older subjects.
OBJECTIVE: The 13C-urea breath test (13C-UBT) is a safe, noninvasive, and accurate test for the detection of Helicobacter pylori (H. pylori) infection in adults. The aim of this study was to evaluate sensitivity and specificity of 13C-UBT in children using different types of test meal, doses of 13C-urea and breath sampling intervals. As yet, a validated, standardized 13C-UBT protocol for children has not been formulated. METHODS: 13C-UBT was performed in 115 children and repeated within 3 days, modifying the test meal or the dose of 13C-urea. H. pylori status was assessed by histology and rapid urease test. 13C-UBT was performed using 100 mg or 50 mg of 13C-urea and a fatty test meal (100 FA; 50 FA), 50 mg of 13C-urea, and a carbohydrate test meal (50 CA). Breath samples were collected every 10 min for 60 min. RESULTS: The 13C-UBT in children was highly sensitive and specific with all three protocols used. The best combination of sensitivity (97.92%) and specificity (97.96%) was obtained with Protocol 50 FA at 30 min with a cut-off of 3.5 per mil. CONCLUSIONS: The 13C-UBT is an accurate test for the detection of H. pylori infection also in children. Administration of 50 mg of 13C-urea, a fatty test meal, and breath sampling at 30 min appears to be the most convenient protocol.
Explore the source record for details and available documents.
Effective treatment regimens are now available for the eradication of Helicobacter pylori, but one of the factors limiting their efficacy is antibiotic resistance. Omeprazole-based triple therapy (omeprazole plus two antibiotics) can, at present, be considered the treatment of choice for H. pylori infection; some of the best results have been achieved by combining omeprazole with either amoxycillin and clarithromycin or metronidazole and clarithromycin. However, the potential effectiveness of nitroimidazole derivatives and clarithromycin must be weighed against the possibility that resistance can develop to these agents. Eradication in metronidazole-resistant strains is lower than in sensitive strains, but is still about 75% (versus 97%). However, clarithromycin resistance is thought to have more clinical significance, reducing the eradication rate of 95% in sensitive strains to 40% in resistant strains, although the overall importance of clarithromycin resistance for H. pylori eradication is still likely to be relatively low. Recent data on secondary resistance indicate that the rate is at least 50% for both metronidazole and clarithromycin in patients in whom eradication has failed. If, in the future, a large number of H. pylori-positive individuals undergo such treatment, treatment failures may become a major issue, and the problem of antibiotic resistance will have to be overcome.
The fact that about 50% of the world's population is infected with Helicobacter (H.) pylori and the important role that this bacterium plays in public health have been important incentives in the search for accurate diagnostic methods. A large number of invasive and non-invasive methods have been used to diagnose H. pylori infection. Each method has its advantages and disadvantages and each practitioner should choose the best diagnostic method according to the facilities available. Non-invasive tests for the diagnosis of H. pylori infection are largely used in clinical practice and in management of patients with gastroduodenal disease. Serology is the most widespread test but its use is not advised in the post-treatment follow-up. The Urea Breath Test is a simple, safe and highly accurate method ideal for evaluating the short-term follow-up of H. pylori eradication after therapy.
The eradication of Helicobacter pylori is advantageous in many diseases of the upper gastrointestinal tract and can result in the cure of conditions such as peptic ulcer disease. It may also potentially prevent the development of gastric cancer. Complete eradication of H. pylori can be difficult to achieve, and the effectiveness of many combinations of agents has been tested in clinical trials over the years. No agent has been found to be effective at eradicating H. pylori when given alone and this has resulted in the development of combination therapies comprising an antisecretory agent and one or more antibiotics. Bismuth-based triple therapies, while considered for years as the 'gold standard', have limited efficacy and may be associated with significant side effects. Dual therapies, comprising a proton pump inhibitor (PPI) and one antibiotic, marked a milestone in the history of H. pylori eradication therapy but have shown inconsistent results and eradication rates of less than 60%. However, these have provided the basis for the development of short-term, low-dose PPI triple therapies, including two antibiotics from among metronidazole, clarithromycin and amoxycillin plus a PPI that have demonstrated excellent eradication rates approaching 100%.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
As provider organizations consolidate and confront managed care pressures, they're looking for laboratory information systems that go beyond the basics. They want lab systems that can integrate with other computer systems, make data available at the point of care, and exchange information over the Internet or intranets. Systems integration efforts, however, are proving troublesome for some CIOs.
BACKGROUND: The classical risk factors for acute myocardial infarction (AMI) fail to explain all the epidemiological variations of the disease. Among the new risk factors recently reported, several infectious agents appear to increase the risk of AMI. In particular, acute and chronic respiratory diseases due to Chlamydia pneumoniae, and Helicobacter pylori (H. pylori) infection seem to be strongly involved. The aim of this work is to determine the prevalence of H. pylori infection in a group of male patients with AMI, in a case-control study, where a group of blood donors matched for sex and age served as control. We searched for the classical risk factors in all patients. METHODS: We studied 212 consecutive male patients, aged 40-65 years, admitted for AMI at the Coronary Care Units at Hospitals in three towns of Northern Italy. H. pylori infection was assessed by the highly specific and sensitive 13C-urea breath test and by presence of antibodies (IgG) against H. pylori in circulation. Volunteer blood donors attending our Hospital Blood Bank served as controls. Among the patients we investigated the presence of hypertension, cholesterol and glucose levels in serum, fibrinogen in plasma and the smoking habit. RESULTS: H. pylori infection was present in 187/212 (88%) of the patients and in 183/310 (59%) of the control population (p < 0.0001). Classical risk factors for AMI did not differ among patients with and without H. pylori infection. CONCLUSION: Patients admitted to the Coronary Care Unit for acute myocardial infarction had a notably higher prevalence of H. pylori infection than the general population. The classical risk factors for coronary disease were equally present in all patients with AMI irrespective of H. pylori status.
A chemiluminescent urease activity assay has been developed and optimized using the chemiluminescent pH indicator phthalhydrazidylazoacetylacetone. This compound is stable at pH </= 7 and decomposes at higher pH values, emitting light in the presence of H2O2. Urease catalyzes hydrolysis of urea to form NH3 and CO2 which increase the pH of the reaction medium, thus allowing the chemiluminescent indicator to decompose and produce photons. The emitted light is proportional to the urease activity when urea is in excess. Urease tests based on colorimetric pH indicators like phenol red are commercially available and commonly used for the rapid diagnosis of Helicobacter pylori infection in gastric mucosa biopsy specimens, since this bacterium produces high amounts of urease. Such colorimetric tests often lack sensitivity, giving false-negative results. The developed chemiluminescent test proved to be at least 50-fold more sensitive than the colorimetric tests, permitting early diagnosis of infection, and it is more rapid, giving results in 1-10 min compared to 30 min. Further applications of this assay could be the in situ localization of urease activity, corresponding to the presence of H. pylori, in gastric mucosa cryosections and the development of high-throughput screening assays of antimicrobial drugs able to inactivate the bacterium.
OBJECTIVE: Dieting obese subjects are at risk of developing gallstones. A gallbladder motor dysfunction could have a pathogenetic role. The principal aim of this study was to evaluate the long term effects of two very low calorie diets differing in fat content on gallbladder emptying and gallstone formation in obese subjects. DESIGN AND SUBJECTS: Gallbladder emptying in response to meals (breakfast, lunch and dinner) in two different diet regimens (3.0 vs 12.2 g of fat/d) was evaluated by ultrasonography in 32 gallstone-free obese patients on different days, before and during (at 45 d intervals) one or two 6-month weight reduction diets (for the first three months: 2.24 MJ (535.2 kcal), 3.0 g fat/d vs 2.415 MJ (577.0 kcal), 12.2 g fat/d; for the second three months, the same low calorie diet of 4.194 MJ (1002 kcal)/d for both groups). In 10 subjects, bile analysis was also performed. RESULTS: Twenty-two (69%) subjects concluded the study, eleven in each group, and a significant weight loss was achieved by all subjects. Gallstones (asymptomatic) developed in 6/11 (54.5%) (P < 0.01) of subjects following the lower fat diet, but in none with the higher fat regimen. In the dieters during the first three months (very low calorie phase) the higher fat meals always induced a significantly greater gallbladder emptying than the lower fat meals. The cholesterol saturation index initially increased significantly and then decreased, without difference between the two groups. CONCLUSION: In the obese during rapid weight loss from a very low calorie diet, a relatively high fat intake could prevent gallstone formation, probably by maintaining an adequate gallbladder emptying, which could counterbalance lithogenic mechanisms acting during weight loss.
BACKGROUND: Studies demonstrating the efficacy of short-term low-dose triple therapies including omeprazole (O), clarithromycin (C) and a nitroimidazole (tinidazole, T) for Helicobacter pylori eradication have largely been open and uncontrolled, and have not assessed antibiotic sensitivity. Simpler regimens using the component drugs have not been evaluated. AIM: To evaluate the OCT regimen in a randomized, controlled trial, testing for pre- and post-treatment antibiotic resistance and comparing, in a factorial design, the OCT regimen with simpler combinations of its components. METHODS: One hundred and twenty-eight patients (68 males, 60 females, age 22-80 years, mean 53 years) with H. pylori gastritis were randomly assigned to one of the following four treatment groups: (C) clarithromycin 250 mg b.d.; (OC) omeprazole 20 mg o.d. + clarithromycin 250 mg b.d.; (CT) clarithromycin 250 mg b.d. + tinidazole 500 mg b.d.; (OCT) omeprazole 20 mg q.d.s. + clarithromycin 250 mg b.d. + tinidazole 500 mg b.d. The drugs were administered for 1 week. Medical interview, upper gastrointestinal endoscopy (with four antral and four corpus biopsies) and the 13C-urea breath test were carried out for all patients prior to and 4 weeks after treatment. Biopsy specimens were used for the urease test, histology, and culture and sensitivities. RESULTS: All but one patient completed treatment. Side-effects were rare and mild in all groups. The eradication rate was 93.8% in group OCT, 59.4% in group CT, 31.3% in group OC and 6.3% in group C. Pre-treatment metronidazole resistance was 12.8%, clarithromycin 1.1% and, to both antibiotics, 2.1%. In patients with pre-treatment metronidazole resistance, the eradication rate was 75% in group OCT and 33% in group CT. Post-treatment resistance to clarithromycin was induced in 28.5% of the failures in group C, but in none of group OC. Resistance to both antibiotics occurred in 22.2% of the failures in group CT and in none of group OCT. CONCLUSIONS: (i) The high efficacy of the OCT regimen is proved and each of the individual components of the regimen is essential to the result, possibly via a synergistic effect. (ii) Pre-treatment metronidazole resistance is scarcely relevant to the outcome. (iii) Acquired resistance is essentially nil if omeprazole is part of the regimen.
BACKGROUND: No clinical study has been performed to-date to evaluate the efficacy of the dual therapy of ranitidine bismuth citrate (RBC) plus clarithromycin (C) 500 mg b.d. given for 7 days for the eradication of H. pylori. AIM: To assess the eradication rates achieved by treatment with RBC 400 mg b.d. for 28 days combined with clarithromycin 500 mg b.d. for 7 days in H. pylori-positive duodenal ulcer patients. METHODS: One hundred and twelve H. pylori-positive patients with endoscopically proven active duodenal ulcer were included in a multicentre, open, randomized trial. H. pylori infection was initially detected by CLO-test and histology on antral and corpus biopsies, and by 13C-urea breath test (UBT). Patients were included if at least two of the tests were positive for H. pylori infection. Patients were randomized to receive RBC 400 mg b.d. for 4 weeks combined with clarithromycin 500 mg b.d. for the first 7 days (Group A) or 14 days (Group B). A second endoscopy was performed at least 28 days after the end of therapy for the assessment of ulcer healing and H. pylori infection. Eradication was assumed if all the tests (CLO-test, histology and UBT) were negative for H. pylori. RESULTS: Fifty patients in Group A and 55 in Group B were assessed for H. pylori eradication and ulcer healing. The eradication rates according to intention-to-treat analysis were 75% in Group A and 80% in Group B. Considering only those patients with evaluable data at least 28 days after the end of therapy, H. pylori eradication was achieved in 84% and 82% in Group A and B, respectively. No statistically significant difference in eradication was found between the two groups by Mantel-Haenszel test. Only one patient, in Group A, was withdrawn because of adverse events (epigastric pain and pruritus).
BACKGROUND: This multicentre, randomized study was designed to assess the clinical efficacy, safety and tolerability of three novel 7-day triple therapies containing ranitidine bismuth citrate (RBC) and two antibiotics. METHODS: We studied patients with non-ulcer dyspepsia and gastritis who were randomly assigned to one of three treatment regimens given for 7 days in a b.d. dosing schedule: RBC 400 mg plus clarithromycin 250 mg and tinidazole 500 mg (RBCCT): RBC 400 mg plus clarithromycin 500 mg and amoxycillin 1 g (RBCCA); RBC 400 mg plus tinidazole 500 mg and amoxycillin 1 g (RBCTA). H. pylori status was determined by CLO-test, histology and 13C-urea breath test. A repeat breath test was performed at least 28 days after completion of therapy to assess eradication. RESULTS: One hundred and fifty-seven patients were eligible for intention-to-treat analysis (ITT) and 140 patients completed the study and returned for assessment of eradication. Intention-to-treat cure rates were 78% with RBCCT, 71% with RBCCA and 61% with RBCTA. An all-patients-treated analysis (APT), performed on evaluable patients, demonstrated eradication rates of 85% with RBCCT, 81% with RBCCA and 70% with RBCTA. No statistically significant difference was found between treatment groups. Twenty-four patients experienced side-effects, but in only seven cases was treatment discontinued due to adverse events. CONCLUSIONS: A 7-day course of RBC, clarithromycin and either tinidazole or amoxycillin provides a good rate of H. pylori eradication. Three novel RBC-based triple therapies proved to be safe and well tolerated, with discontinuations due to side-effects occurring in less than 5% of cases.