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A Ponzetto

Publications and source records attributed to A Ponzetto.

At least 19 recordsLinked to original sources
PubMed2005

[Intestinal metaplasia, dysplasia, gastric cancer and Helicobacter pylori: epidemiological observations].

Gastric cancer (GC) is the world's second leading cause of cancer-related mortality, and carries a bad prognosis. In 1994, Helicobacter pylori (H. pylori) has been classified by the International Agency for Research on Cancer as a group I carcinogen. There are increasing indications that this infection is associated with both the initiation and progress of gastric carcinoma and lymphoma. Evidence supporting a causal association has been demonstrated by epidemiological data and in experimental animal models. Despite this, there is still lack of final conclusion regarding the association between the infection and the malignancy due both to marked geographic variations and heterogeneity in study designs. Given the high rate of morbidity and mortality associated with GC, any means of reducing the occurrence of the disease or increase its early detection is most desirable. In this paper, the epidemiological aspects on the evidence of a causal relationship between H. pylori and GC are discussed. Prospective cohort studies and interventional trials focused on the effects of H. pylori eradication on lesions predisposing to GC should be performed in order to provide further data.

Adenocarcinoma↗
PubMed2005

How accurate is the culture of Helicobacter pylori in a clinical setting? An appraisal.

AIM: The trend towards increasing prevalence of Helicobacter pylori (H. pylori) antibiotic resistance may jeopardize the efficacy of most regimens. Culture of the bacterium, the useful method able to address therapy, is influenced by various factors. Thus, validation of the procedure is fundamental. Most studies have been carried out in microbiological settings, while only few have been conducted in clinical frames. We evaluated the accuracy of culture for detection of H. pylori in a clinical dedicated laboratory. METHODS: Forty-six patients (28 females, 18 males, mean age 56+/-4.7 years) were included. Thirty experienced failure to H. pylori eradication after at least 3 courses of treatment. The control group included 16 subjects suffering from gastroesophageal reflux disease and negativity for H. pylori infection. Diagnostic strategy was based on histology, culture testing, serology and 13C-urea breath test. A patient was considered infected if 2 tests were positive. A commercial culture medium in microaerophilic atmosphere was utilized. RESULTS: Out of 30 positive specimens, culture correctly identified 29. In 1 case, no growth of micro-organisms occurred. In the control group, bacterial culture accurately identified all negative samples. One of them indicated growth but neither aspect nor confirmation tests identified H. pylori. Sensitivity was 96.7%, specificity 100%, and accuracy 97.8%. Positive and negative predictive values were 100% and 94.1%, respectively. CONCLUSIONS: Culture of H. pylori is a feasible method and provides a good level of diagnostic accuracy even in a clinical setting by following international guidelines combined with training of specialized personnel.

Breath Tests↗
PubMed2004

Gastro-oesophageal reflux disease and asthma: would be possible to improve therapy on the basis of what is now known?

Gastro-oesophageal reflux disease (GORD) is a chronic and relapsing clinical condition, associated or not to histopathologic alteration resulting from repeated contact of oesophageal mucosa with gastric content. This condition occurs with high prevalence in the general population and represents one of the most frequent reasons for health care-seeking addressed to primary care physician and gastroenterologists. A plethora of extra-oesophageal manifestations have been described in patients suffering from GORD and a causal relationship has been postulated by many investigators. A large cohort of studies has focused on the possible cause-effect interaction between GORD and asthma. However, despite the improvement in both asthma symptoms and medication requirements after anti-secretory therapy, no change in pulmonary function is evident. Furthermore, the pathogenetic mechanism, a vagally mediated reflex, microaspiration or increasing reactivity to the stimuli, is yet unclear. Since conflicting conclusions and the failure to find a causal relationship are generally due to the heterogeneity of the studies, further research is needed to clarify the role of GORD in asthma pathogenesis, or viceversa, and whether a medical or surgical anti-secretory treatment may be an approach to curing the asthma patients non-responders to the classical therapy.

Asthma↗
PubMed2004

[The diagnosis of helicobacter pylori infection: guidelines from the Maastricht 2-2000 Consensus Report].

The European Helicobacter pylori Study Group (EHPSG), during the Maastricht 2-2000 Workshop, revised and updated the original guidelines on the management of Helicobacter pylori (H. pylori) infection. The present review focuses on the diagnostic approach for patients referred to the primary care as well as to the specialist. Currently, two diagnostic methods can be used to detect H. pylori: invasive (urease test, histological detection, culture, polymerase chain reaction, smear examination, string test) or non-invasive (serology, urea breath test, antigen stool assay, ''doctor's tests'') tests. These methods vary in their sensitivity and specificity, and the choice depends on the situation, for example, whether the aim is to detect infection or the success of eradication treatment. Urea breath test (UBT) and antigen stool assay are recommended from EHPSG in patients without alarm symptoms or under 45 years of age, at low risk of malignancy in the ''test and treat strategy''. Confirmation of H. pylori eradication following treatment should be tested by UBT; a stool antigen assay is the alternative if the former is not available. Important added value can be gained from other tests: histology allows evaluation of the status of the mucosa while culture allows strain typing and tests for antibiotic susceptibility.

Adult↗
PubMed2003

Helicobacter pylori infection in patients with Hepatitis C Virus positive chronic liver diseases.

BACKGROUND AND GOALS: One-third of patients with liver cirrhosis suffers from acute peptic ulcer, a disease strongly correlated with Helicobacter pylori (H. pylori) infection. We report the seroprevalence of antibodies to H. pylori in 179 patients with Hepatitis C Virus (HCV)-related chronic active hepatitis and cirrhosis. MATERIALS AND METHODS: Among patients, 135 (86 males and 49 females, mean age 51.2 +/- 13.28, range 27-77 years) had chronic active hepatitis (CAH) and 44 cirrhosis (28 males and 16 females, mean age 62.4 +/- 9.2, range 37-77 years). Serum antibodies to H. pylori were tested using a commercial enzyme immunosorbent assay. The control population consisted of 619 consecutive blood donors (523 males, 96 females, mean age 47 +/- 5.3 years, range 18-65). RESULTS: The overall prevalence of antibodies to H. pylori was 73.1% (131/179) among patients and 47% (291/619) among blood donors (p<0.0001; OR 3.08 [95%CI, 2.10-4.51]). 70.5% (24/34) of patients aged less than 40 years were seropositive for H. pylori versus 34.2% (90/263) of controls (p<0.0001; OR 4.61[95%CI, 2.0-10.85]). Among cirrhosis patients, the prevalence of antibodies to H. pylori was 79.5% (35/44) versus 47% (291/619) of controls (p<0.0001; OR 4.38 [95%CI, 1.98-9.98]). Overall seroprevalence among CAH patients was 71.1% (96/135) versus 47% (291/619) of blood donors (p<0.0001; OR 2.77 [95%CI, 1.82-4.24]). CONCLUSIONS: The high seroprevalence of antibodies to H. pylori in patients with HCV-positive liver diseases explains the elevated incidence of peptic ulcer, and warrants studies on the pathogenic role in human liver diseases of Helicobacter spp which is known to cause chronic hepatitis and hepatocellular carcinoma in mice.

Adult↗
PubMed2003

Helicobacter pylori seropositivity in patients with unstable angina.

AIM: The pathogenesis of ischemic heart diseases has been correlated, on epidemiological and pathogenetic grounds, with infections by viruses and bacteria, including Helicobacter pylori (H. pylori). THE AIM: of this study were to investigate the association of unstable angina (UA) with anti-H. pylori seropositivity in a case-control study and to search for the classic cardiovascular risk factors in both infected and uninfected patients. METHODS: We studied 32 consecutive patients (20 males, 12 females), mean age 65 years (range 42-89), with final diagnosis of UA. A total of 64 subjects (40 males, 24 females, mean age 65 years, range 42-89) admitted to the Emergency Care Unit, age and sex-matched, served as controls. The presence of hypertension, serum levels of cholesterol and glucose, plasma levels of fibrinogen, smoking habit and social class were investigated in all patients. Cases and controls were inhabitants of NorthWestern Italy, and had similar socioeconomic status as based on working place and on instruction level. H. pylori seroprevalence was assessed by the presence of antibodies (IgG) against H. pylori by means of a commercial enzyme immunosorbent assay. RESULTS: Antibodies to H. pylori were found in 26/32 (81%) of the patients and in 34/64 (53%) of the controls (p=0.007); the odds ratio was 3.82 (95% confidence interval 1.27 to 12.04). Classical cardiovascular risk factors, such as socio-economic status, did not differ among patients with and without antibodies to H. pylori. CONCLUSION: Patients with unstable angina had a significantly higher seroprevalence of anti-H. pylori than the control population. Classical risk factors for ischemic heart disease, such as the indicators of socio-economic status, were equally distributed among infected or uninfected patients with UA.

Adult↗
PubMed2002

Mixed cryoglobulinaemia and chronic hepatitis C virus infection: the rheumatic manifestations.

The prevalence of rheumatologic symptoms in patients with mixed cryoglobulinaemia associated to chronic hepatitis C virus (HCV) infection was investigated. One hundred fourteen patients (96 female, mean age 63.5 years) with chronic HCV infection and cryoglobulinaemia were recruited. The presence, concentration, and type of cryoglobulins were tested by immunofixation. Rheumatoid factor (RF) and antinuclear antibody (ANA) were also measured. Rheumatological related symptoms were investigated by anamnesis and clinical evaluation. HCV genotype was determined by polymerase chain reaction (PCR) with genotype specific primer. Type II cryoglobulinaemia was identified in 39 cases and it was of type III in 58. HCV-RNA genotype was determined in 62 patients: 47 (76%) were infected by genotype1b, 8 (13%) by genotype 2a, while other genotypes were less common. RF and ANA were, respectively, present in 36 (31.5 %) and 4 (3.5 %) patients at low titre (RF < 50 UI/ml, ANA < 1:80). Of the 114 patients, 51 (44.7%) complained for rheumatological symptoms. The mean cryocrit value in these patients was 2,6 %, while in patients with HCV infection, liver disease, and cryoglobulinaemia without rheumatological symptoms the cryocrit value was lower than 0.5% in 50% of cases. It is concluded that patients with chronic HCV infection reported a wide variety of rheumatological manifestations, impairing their quality of life, with discrete frequency. These results suggest that HCV infection should be considered in the differential diagnosis of rheumatological symptoms of unknown origin.

Antibodies, Antinuclear↗
PubMed2002

Elevated serum chromogranin A in patients with hepatocellular carcinoma.

Chromogranin A is a cellular marker forneuroendocrine tumors. Elevated levels of chromogranin A are also found in patients with cancers of epithelial origin when neuroendocrine differentiation occurs, which is associated with a poor prognosis. We investigated the prevalence of serum levels of chromogranin A in patients with primary liver cancer. Seventy-nine patients (65 males, mean age 67.6 years, range 48-88 years) with liver cirrhosis and hepatocellular carcinoma were studied. The etiology of cirrhosis was identified as due to hepatitis C virus infection in 47 patients, to hepatitis C virus and alcohol in 7, to alcohol alone in 14, to hepatitis C and B virus in 2, and to hepatitis B virus alone in 4. Of the remaining patients, 2 suffered from hemochromatosis and 3 had cryptogenic cirrhosis. According to the Child-Pugh's score, 54 patients belonged to class A, 22 to class B, and 3 to class C. The concentration of chromogranin A was measured in serum with a commercial solid-phase two-site immunoradiometric assay. Elevated serum levels of chromogranin A were found in 32 of 79 patients (43%). Levels over 600 ng/ml were present in 7 of 76 patients (9.2%), all of whom had very high serum levels of alpha-fetoprotein. Hence, elevated serum levels of chromogranin A are present in over one third of patients with hepatocellular carcinoma. It is therefore possible that some hepatocellular carcinomas could acquire a neuroendocrine differentiation. We propose further studies to ascertain whether serum levels of chromogranin A are useful as a prognostic marker for hepatocellular carcinoma as in prostate cancer.

Aged↗
PubMed2002

Helicobacter pylori infection and infertility.

OBJECTIVE: To determine (1) the prevalence of Helicobacter pylori infection in male and female patients with reproductive disorders and controls; (2) the presence of anti-H. pylori antibodies in samples of follicular fluid, vaginal secretions and sperm; and (3) the existence of a structural homology between a major spermatozoa protein, tubulin, and H. pylori proteins. PATIENTS AND METHODS: Serum samples from 167 patients with infertility and 837 age- and gender-matched controls (blood donors) were examined by enzyme-linked immunosorbent assay (ELISA) and Western blotting to determine the seropositivity for H. pylori infection. The presence of anti-H. pylori antibodies in samples of follicular fluid, vaginal secretions and sperm was determined using the same techniques. The possible cross-reactivity with spermatozoa of anti-H. pylori hyperimmune sera and human antibodies was studied by immunofluorescence. The N-acid homology of human tubulin with the principal H. pylori proteins was assayed by the WU-blastp program available on the Internet. RESULTS: The prevalence of infection was significantly higher in patients than controls (49.1% v. 33.5%, P < 0.001). Follicular fluids from infected patients contained specific antibodies in all cases, sperm samples in about 50% of cases, and vaginal secretions in a minority of cases. Sera to H. pylori whole antigens and VacA reacted with the tails and the pericentriolar area of human spermatozoa (which are rich in tubulin); sera to urease and heat-shock protein (Hsp) did not. Follicular fluids with anti-H. pylori antibodies immune reacted with spermatozoa. A linear homology was found between beta-tubulin and three H. pylori proteins, flagellin, VacA and CagA. CONCLUSIONS: H. pylori infection may increase the risk of developing reproductive disorders or worsen the clinical expression of this syndrome.

Adolescent↗
PubMed2002

Infection by Helicobacter pylori and acute myocardial infarction. Do cytotoxic strains make a difference?

The classical risk factors for acute myocardial infarction (AMI) fail to explain all the epidemiological variations of the disease. Among the risk factors recently reported, several infectious agents appear to increase the risk of AMI. Helicobacter pylori (H. pylori) infection, a bacterium involved in duodenal and gastric ulcer, gastric cancer and MALT-lymphoma, seems to be strongly associated with AMI. More virulent (anti-CagA positive) strains of the bacterium are almost exclusively the causative agents of such diseases. To determine the prevalence of H. pylori infection and of virulent strains, a case-control study was conducted in a group of male patients with AMI. A group of patients consecutively admitted to the Emergency Care Unit served as controls. We studied 223 consecutive male patients, mean age 60.2 (range 40-79) years, admitted for AMI to the Coronary Care Units at Hospitals in two towns of Northern Italy, 223 age matched male patients (mean age 61.8, range 40-79 years) admitted to the Emergency Care Unit, served as control. H. pylori seroprevalence was assessed by presence of antibodies (IgG) against H. pylori and anti-CagA in circulation. Among the patients we investigated the presence of hypertension, levels of cholesterol and glucose in serum, fibrinogen in plasma and smoking habits. H. pylori infection was present in 189/223 (84.7%) of the patients and in 138/223 (61.8%) of the control population (p < 0.0001 OR 3.42 [IC 95% 2.12-5.54]). The anti-CagA antibodies were detected in 33.8% of infected patients with AMI (64/189) versus 26.8% in the control subjects (37/138) (p:0.17, OR 1.40 [IC 95% 0.84-2.33]). Classical risk factors for AMI did not differ among patients with and without H. pylori infection. Patients admitted to the Coronary Care Unit for acute myocardial infarction had a notably higher prevalence of anti-H. pylori not restricted to virulent strains, when compared to a population of patients referred to the Emergency Care Unit. The classical risk factors for coronary disease were present in the patients with AMI irrespective of H. pylori status.

Adult↗
PubMed2002

Decreasing eradicaton rate of Helicobacter pylori infection with metronidazole-based triple therapy. A randomised study.

BACKGROUND: Helicobacter pylori (H. pylori) infection plays an important role in the pathogenesis of duodenal ulcer (DU) disease. Low DU recurrences and reinfection rates were universally described, when treatment was effective. It has been suggested that short-term triple therapy, comprising a proton pump inhibitor plus two antibiotics (clarithromycin, amoxicillin or a nitroimidazole), should be used as first choice in treating H. pylori infection. Nevertheless, conflicting results have been reported on using these treatment regimens in different countries, due to the resistance of H. pylori against one or more antibiotics. Our aim was to compare the efficacy, for H. pylori eradication, of 1-week triple therapy versus 10 and 14-day triple schedules, in patients with a history of recurrent DU. METHODS: A total of 159 patients (85 males, mean age 59.2+/-3.2 years) was randomly treated with a triple therapy including a standard dose of omeprazole twice daily, amoxicillin 1 g twice daily and metronidazole 500 mg twice daily. Fifty-three patients received 1-week triple therapy (Group I), 53 subjects were treated with 10-day triple therapy (Group II) and 53 others with 14-day triple therapy (Group III). H. pylori infection at entry and eradication, at least 4 weeks after therapy had ended, was assessed by 13C urea breath test and histology on biopsies from the antrum and the corpus. RESULTS: Of the 159 subjects randomised into the study, 6 (3 in group II and 3 in group III) were excluded from the per protocol (PP) analysis because of discontinuations. At the end of the course of treatment, the overall H. pylori eradication rate in the intention-to-treat analysis, was 73.5% (39/53) in group I, 71.6% (38/53) in group II and 73.5% (39/53) in group III, without any statistically significant difference. Moreover, the PP analysis also showed no statistical differences, with an eradication rate of 73.5% (39/53) in group I, 76% (38/50) in group II and 78% (39/50) in group III. The reported frequency of side-effects was evenly distributed between the groups, but 6 patients (3.7%) stopped because of adverse events only in groups II and III. CONCLUSIONS: The present study shows that there is no significant difference between the three regimens although the 14-day triple therapy shows a slightly higher H. pylori eradication rate. There is a strong need, in our region, to put forward surveillance programmes to monitor the prevalence of local resistant strains and to guide treatment on the basis of resistance patterns.

Journal Article↗
PubMed2001

New high-performance liquid chromatographic method for the detection of picolinic acid in biological fluids.

A HPLC method is described to quantify picolinic acid in milk, blood serum and tissue culture supernatant. The method requires very little sample preparation because acid precipitation allows total recovery of picolinic acid. High specificity and sensitivity were obtained using ion-pair chromatography on a C18 reversed-phase column with tetrabutylammonium hydrogen sulfate as ion pairing reagent. We describe the conditions for the automated testing of multiple samples and for the detection of L-tryptophan and L-kynurenine together with picolinic acid. This system will be utilized to elucidate the relationship between picolinic acid production and human disease. Furthermore, we provide the first evidence of picolinic acid in human blood serum.

Animals↗
PubMed2001

The effect of the eradication of Helicobacter pylori infection on hemorrhage because of duodenal ulcer.

The cost of a recurrently bleeding duodenal ulcer (DU) is very high, both from a human and an economic point-of-view. Helicobacter pylori infection plays an important role in the pathogenesis of DU disease and its complications, such as bleeding. Cure of H. pylori infection is recommended in patients with DU and its complications, although in the latter case, the most efficient management is not yet a defined issue. In particular, acid secretion inhibitors may not contribute to long-term cure. Our aims were to ascertain whether the recurrence of bleeding because of DU could be prevented by H. pylori eradication and whether long-term inhibition of gastric acid output is needed to prevent recurrence. Eighty-four patients (65 men; mean age, 55.1 years), who had bled because of recurrent DU, were followed after the cure of H. pylori infection. None of the patients were on therapy with nonsteroidal antiinflammatory drugs. Successful cure of H. pylori was determined by gastroscopy, histology, and serology performed at 3, 6, 12, 24, and 48 months after the eradication treatment. A 13C urea breath test was performed when the results of serology were unclear and also at recurrence of DU or bleeding. After the antibiotic treatment, 46 patients stopped all medications, whereas 38 continued long-term therapy with histamine type 2 receptor antagonists. During a mean follow-up period of 47.2 months (range, 37-65 months), recurrence of DU at endoscopy was observed in three patients in each group (p = 0.56), but none bled again. We conclude that H. pylori eradication prevents DU recurrence and rebleeding, that reinfection rate by H. pylori after cure was nil at 4 years, and that long-term inhibition of acid secretion may not improve outcome after cure of H. pylori, even in patients whose DU was complicated by hemorrhage.

Duodenal Ulcer↗
PubMed2001

[Gastroenterologists in ambulatory care. The experience in Turin in the year 2000].

BACKGROUND: Digestive diseases (GI) have a major impact on public health in Italy. Hospital stay for digestive pathologies parallels that due to cardiovascular causes. Total mortality for GI causes is also very high. The management of GI pathologies is therefore a major task for the National Health System. To the experienced gastroenterologist it is clear that a large number of hospitalisation is linked to a lack of careful outpatient follow-up of diseases such as cirrhosis, ulcerative colitis and peptic ulcer. METHODS: One year of activity of our Gastro-entero-Hepatology outpatient service is examined. The management of the majority of GI diseases is organized in working teams of physicians and surgeons following cohorts of patients suffering of a specific disease. RESULTS: During the year 2000 not only a statistically significant higher number of patients has been examined (p<0.05), in comparison with 1994, but also the hospitalisation rate was lowered resulting in a very significative cost-containment. CONCLUSIONS: The specialization of outpatient activities into working teams offers advantages in terms of more appropriate medical care and cost reduction, partly due to a less frequent hospitalisation. The obvious counterpart was an increase of request of such form of follow-up from patients, resulting in longer delay to the access.

Ambulatory Care↗
PubMed2001

[Gastroesophageal reflux disease and chest pain].

Gastroesophageal reflux disease (GERD) is highly prevalent in the general population. Heartburn and acid regurgitation are considered the typical presentation of GERD, that however might represent a major pathogenic mechanism in patients with chest pain without coronary artery disease. Chest pain in this instance is often successfully treated with high-dose antisecretory drugs, but the pathogenetic mechanism remains unclear. Further research is needed to clarify the role of GERD on the pathogenesis of chest pain and to ascertain whether a medical or surgical anti-secretory treatment could represent a possible approach. Patients with non-cardiac chest pain of unknown origin should be carefully screened for the occurrence of GERD.

Barrett Esophagus↗
PubMed2001

Helicobacter pylori seroprevalence in hepatitis C virus positive patients with cirrhosis. The Como cross-sectional study.

BACKGROUND: Liver cirrhosis is a significant cause of death in Italy and one of the most frequent causes of hospitalization. Acute peptic ulcer and upper gastrointestinal bleeding reportedly occur in over 15% of cirrhotic patients. Since Helicobacter pylori (H. pylori) infection strongly correlates with peptic ulcer, we sought to ascertain the seroprevalence of H. pylori infection in cirrhotic patients. METHODS: In a cross-sectional study, we examined 52 consecutive patients (31 female and 21 male, age range 54-82, mean 68.7 years) suffering from hepatitis C virus (HCV)-related cirrhosis attending the Unit of Gastroenterology of the Valduce Hospital of Como (Italy). RESULTS: The prevalence of antibodies against H. pylori was 86.5% (45/52) in the cirrhotics. Of female patients 28/31 (90.3%) were seropositive as compared to 17 of 21 (80.9%) of male patients. CONCLUSIONS: The very high prevalence of H. pylori infection may explain the frequent occurrence of gastroduodenal ulcer in cirrhotic patients.

Aged↗
PubMed2001

The journey from hepatitis to hepatocellular carcinoma. Bridging role of Helicobacter species.

Hepatocellular carcinoma (HCC) is a long-term consequence of chronic liver disease, whose aetiology could result from viral, environmental and hereditary causes. Viral infection, by itself, could only partially explain the pathogenesis of cirrhosis and HCC. A new aetiologic agent capable of inducing chronic active hepatitis and hepatocellular tumours was discovered: it is a bacterium belonging to the genus Helicobacter, and named H. hepaticus. Presence of sequences belonging to the 16S rRNA of Helicobacter species (spp.) has been demonstrated in liver of most patients with cirrhosis and HCC. H. pylori and related bacteria, such as H. hepaticus, produce toxins that kill hepatocyte by a granulating effect on liver cell lines. In vivo, such toxins might reach the liver through the portal tract, thereby causing hepatocellular damage. The recognition of Helicobacter spp. as a possible risk factor for cirrhosis and HCC might have a practical impact on the general population: the treatment of this infection is easy and far less expensive than liver transplantation or any long term treatment for the other risk factors of HCC. Any confirmation of the involvement of Helicobacter in liver disease would eventually come from the success of culturing the bacterium from liver tissues. Future research is needed to clarify the importance of Helicobacter spp. in respect to the other pathogens already known as causative agents of chronic inflammation of the liver and its long term sequelae, namely cirrhosis and HCC.

Animals↗