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F Bonvicini

Publications and source records attributed to F Bonvicini.

At least 19 recordsLinked to original sources
PubMed2007

Assessment of the presence of mucosal human papillomaviruses in malignant melanomas using combined fluorescent in situ hybridization and chemiluminescent immunohistochemistry.

BACKGROUND: The vast majority of studies aimed at detecting human papillomavirus (HPV) DNA in skin cancer have used sensitive polymerase chain reaction (PCR) methods but the PCR technique, despite its high sensitivity, is not suitable to ascertain whether (i) the presence of HPV can be related only to few cells harbouring the virus, (ii) the presence of HPV is due to a tumour surface contamination and (iii) the presence of HPV is localized in cancer cells, rather than in normal keratinocytes present in the tumour biopsy. In a recent work we have found mucosal high-risk (HR) HPV genotypes in primary melanoma by PCR. OBJECTIVES: To localize mucosal HR-HPV nucleic acids and tumoural melanocytic marker in the same sections of primary melanoma samples in order to understand the relationship between HPVs and melanoma cells. METHODS: We have developed a very sensitive method that combines an enzyme-amplified fluorescent in situ hybridization (ISH) for the detection of HPV nucleic acids (types 16 and 18) with a chemiluminescent immunohistochemistry (IHC) method for the detection of the tumoural melanocytic marker HMB-45 sequentially in the same section. Digital images of fluorescent ISH and chemiluminescent IHC were separately recorded, assigned different colours and merged using specific software for image analysis. RESULTS: The combined fluorescent ISH and chemiluminescent IHC demonstrated a sharp colocalization (in the range 60-80%) of HPV nucleic acids and melanoma marker inside the same sections of melanoma biopsies, with a strong specificity and sensitivity. CONCLUSIONS: The strong colocalization of mucosal HR-HPV nucleic acids and HMB-45 melanocytic marker emphasized that viral nucleic acids were specifically present in melanoma cells and supported a possible active role of HPV in malignant melanoma.

Adult↗
PubMed2005

Pegylated interferon plus ribavirin for recurrent Hepatitis C infection after liver transplantation in naïve and non-responder patients on a stable immunosuppressive regimen.

BACKGROUND: Hepatitis C virus recurrence after liver transplantation is universal, leading to chronic hepatitis and cirrhosis. AIMS AND PATIENTS: We evaluated the efficacy and safety of pegylated interferon and ribavirin in 20 patients with recurrent Hepatitis C virus after liver transplantation (10 naïve and 10 non-responders to a previous interferon course). METHODS: Treatment consisted of pegylated interferon alfa-2b (1.0 microg/kg once weekly) and ribavirin (600 mg/daily) for at least 6 months. Therapy continued for an additional 6 months only in patients with undetectable serum Hepatitis C virus-RNA or >2 log drop from baseline levels. RESULTS: Eleven out of 20 patients (55%) completed 1 year of treatment. Nine patients (45%) had undetectable Hepatitis C virus-RNA at the end of treatment, six of them were naïves and three non-responders. In all of them, virological response persisted 6 months after discontinuation of therapy, so the sustained virological response rate was 60% in naïve patients and 30% in non-responders. CONCLUSIONS: Our results suggest that pegylated interferon plus ribavirin combination therapy may be effective in patients with post-liver transplantation recurrent chronic Hepatitis C, even in those previously non-responders to interferon plus ribavirin. These results need to be confirmed by large studies.

Aged↗
PubMed2005

Presence and type of oncogenic human papillomavirus in classic and in differentiated vulvar intraepithelial neoplasia and keratinizing vulvar squamous cell carcinoma.

The presence and type of oncogenic papillomavirus (HPV) in classic warty/basaloid vulvar intraepithelial neoplasia and in differentiated vulvar intraepithelial neoplasia and keratinizing vulvar squamous cell carcinoma was investigated using three techniques, that is, histology, in situ hybridization, and PCR-ELISA. HPV typing was performed using in situ hybridization and PCR-ELISA. Differentiated vulvar intraepithelial neoplasia and invasive keratinizing vulvar squamous cell carcinoma proved completely negative for HPV by PCR-ELISA, in situ hybridization, and histologic examination, while in classic vulvar intraepithelial neoplasia, a HPV positivity of 66.1% was found. HPV 16 was the predominant type, with HPV 35, 33, and 52 types found rarely and sometimes together with HPV 16. PCR-ELISA proved to be the most suitable method to detect and type mucosal oncogenic HPVs. The absolute absence of HPV DNA in differentiated vulvar intraepithelial neoplasias and in keratinizing vulvar squamous cell carcinoma suggests a strong HPV-independent pathway of malignant progression to invasive carcinoma.

Adult↗
PubMed2005

Presence of high-risk mucosal human papillomavirus genotypes in primary melanoma and in acquired dysplastic melanocytic naevi.

BACKGROUND: Some studies have shown that cutaneous and mucosal melanoma biopsy specimens harbour human papillomavirus (HPV), suggesting that this virus may play a role in development and progression of the tumour. OBJECTIVES: To investigate the presence of HPV DNA and the prevalence of different high-risk mucosal HPV genotypes in primary melanoma (PM) and in acquired dysplastic melanocytic naevi (ADMN). METHODS: Fifty-one PMs from 18 men and 33 women (median age 55.5 years), 33 ADMN from 15 men and 18 women (median age 35.1 years) and 20 control skin samples from nine men and 11 women (median age 43.5 years) were studied. All diagnoses were made after histological analysis. HPV DNA analysis was made using two different polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA) methods, namely MY-PCR and GP-PCR. RESULTS: Using GP-PCR, mucosal HPVs were detected in 14 PMs (27%; P = 0.0166) and eight ADMN (24%; P = 0.0367), while with MY-PCR, mucosal HPVs were found in 11 PMs (22%; P = 0.04) and five ADMN (15%; P not significant). All control skin samples were negative for mucosal HPVs with both DNA amplification procedures. CONCLUSIONS: Using our PCR-ELISA methods, the detection of mucosal high-risk HPV genotypes in 24% of precursor lesions (ADMN) and in 27% of PMs adds to the body of evidence indicating a colocalization of mucosal HPV and tumoral melanocytic pathologies.

Adolescent↗
PubMed2004

Molecular testing for detection of in vitro infectivity of plasma pools contaminated with B19 virus.

B19 virus can be transmitted by contaminated blood or blood products. Recent observations, in healthy volunteers, suggest that active B19 infection can follow the administration of plasma pools with a concentration > or =10(7) genome equivalents/ml (geq/ml) of B19 DNA. However, patients receiving batches with levels of virus DNA lower than 10(4) geq/ml do not show any evidence of transmission of the virus. The aim of the study was to show, by in vitro assays, a threshold of viral load in B19 contaminated plasma pools over which the infection can be transmitted. Twenty plasma pools, each containing 960 single donations, were tested to correlate the viral load and the level of antibodies anti-B19 with the in vitro infectivity and expression of B19 virus. All the plasma pools, titrated for B19 viral load by competitive PCR, were inoculated into KU812Ep6 erythroid human cell line. Five of the nine contaminated plasma pools, with a B19 DNA concentration > or =3.60 x 10(6) geq/ml, were able to infect KU812Ep6 cells. In vitro infectivity was shown in KU812Ep6 cells at 24 h post-infection by in situ hybridisation and amplification assays for viral DNA and RNAs. Plasma pools with a viral load in the range of 6.00 x 10(3)-8.96 x 10(4) geq/ml did not show infectivity when inoculated into KU812Ep6 cells. Medium-high titres of IgG antibodies anti-B19 were detectable in all the plasma pools and the neutralising activity associated with specific IgG anti-B19 may explain the lack of infectivity of plasma pools contaminated with a low viral load. In conclusion, in situ hybridisation and amplification assays for viral DNA and RNAs in KU812Ep6 cells inoculated with plasma pools can be valid assays to test for the presence of infectious virus in the production of B19-safe material.

Antibodies, Viral↗
PubMed2004

Efficient treatment of paraffin-embedded cervical tissue for HPV DNA testing by HC-II and PCR assays.

BACKGROUND AND OBJECTIVES: High-risk human papillomaviruses (HR-HPVs) are the primary cause of cervical cancer. In order to meet with clinical requirements, a direct capture test with signal amplification (HC-II), able to detect the 13 prevalent HR-HPVs, has been developed and validated for cytological specimens. STUDY DESIGN: the use of HC-II assay with formaldehyde-fixed paraffin-embedded cervical biopsies, for retrospective studies or to support histological findings, was investigated by analysing three different sample treatments. The efficacy of this test was compared with a reference PCR-ELISA, using MY09/11 and GP5+/6+ consensus primers and the use of a single extraction method for both HC-II and PCR-ELISA assays was validated. RESULTS: protease treatment of dewaxed biopsy sections allowed an optimal performance of HC-II and has also been validated for PCR-ELISA. Overall, on the analysis of 50 cervical samples HC-II and PCR-ELISA assays showed a high concordance (K=0.80). Compared with PCR-ELISA, the HC-II had a sensitivity of 86.4% and a specificity of 92.9%. The results showed that short amplimers are necessary for a sensitive PCR-ELISA from formaldehyde-fixed paraffin-embedded biopsies, while HC-II showed a relatively low sensitivity for HPV18 within the HR probe pool. CONCLUSIONS: HC-II can be a valid tool for the diagnosis of HPV infection in biopsy material. The possibility to use the same specimen preparation material for both HC-II and PCR-ELISA allows HC-II positive specimens to be further processed by PCR-ELISA if specific genotyping is needed.

Biopsy↗
PubMed2003

Relevance of B19 markers in serum samples for a diagnosis of parvovirus B19-correlated diseases.

In order to evaluate the optimal and essential diagnostic test(s) for a correct diagnosis of B19 diseases, 344 consecutive serum samples were tested from 344 patients with clinical suspicion of B19 infection during an epidemic period (early Spring-Autumn 2000). Sera were tested for B19 DNA by a standardized competitive polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA) and dot-blot hybridization and for specific IgM and IgG by ELISA. Of 344 patients examined, 125 were positive for markers of B19-associated disease: 49 had both B19 DNA and IgM, 50 had B19 DNA without IgM, and 26 had IgM without B19 DNA. After examination of the different patterns of B19 markers as diagnostic tools for B19 infection, IgM determination detected only 60% of B19-documented infections. IgM tests were nevertheless fundamental, as they were the unique diagnostic marker in 20.8% of documented infections (26 of 125 patients), in the diagnosis of recent, but still symptomatic infections when B19 DNA was no longer detectable. The determination of B19 DNA with PCR permitted detection of 79.2% of infections and therefore represented an essential test. PCR was fundamental for the diagnosis of B19 disease, as the unique diagnostic marker in 32% of documented infections (50 of 125 patients), both in acute infections at the onset of symptoms before the appearance of immunological response, and during the course of persistent B19 infections in which IgM had cleared. The contemporaneous determination of B19 DNA by PCR and specific IgM appears to be the most appropriate diagnostic protocol for the correct laboratory diagnosis of B19 infection.

Antibodies, Viral↗
PubMed2002

Evaluation of commercial kits for the detection and typing of human papillomavirus in cervical swabs.

Human papillomaviruses (HPV) detection by MY consensus primers amplification within the L1 region and typing of prevalent genital HPVs by reference and commercial sets of probes was compared by PCR-ELISA systems. The specificity of commercial probes used in the L1 HPV Geno-Kit with respect to the reference probes proved to be 100%, with an overall agreement of 97.6%. The discordant results concerned only the detection of HPV 16, both as single genotype present in the sample and as multiple infections. The analytical sensitivity of the commercial probe for HPV 16 proved to be slightly less sensitive than the reference probe in the hybridisation conditions of the PCR-ELISA system. The L1 PCR-ELISA reference system was evaluated further in comparison with commercial E6/E7 consensus PCR and microplate hybridisation by typing kit. Amplified products of both the L1 and E6/E7 consensus regions were also analysed by agarose gel electrophoresis. An overall concordance of 95.2% was found. On account of its specificity and sensitivity the E6/E7 commercial system proved to be particularly useful for diagnostic laboratory, as it detects only the prevalent high risk genotypes. The agarose gel detection can therefore be used as screening test, thus reducing the costs, while the E6 E7 HPV Geno-Kit High Risk can be used when specific typing is required.

Capsid Proteins↗
PubMed2002

Diagnostic procedures in B19 infection.

In immunologic normal hosts, both children and adults, B19 can cause acute, generally self-limiting diseases. The infection leads to a viremia that can be present, at high titre, for about one week, then the onset of a specific immune response controls the infection. B19 infection in pregnancy can be associated with non-immunologic foetal hydrops or foetal death. In immunocompromised hosts, B19 can persist over several months and sometimes years. Persistent or recurrent B19 infections can be associated with chronic clinical manifestations or with transient clinical syndromes, generally related to the recrudescence of viral replication. Since the infection has been associated with a wide variety of clinical manifestations and some clinical features of B19 infection, such as anemia, artropathy and rash, can be common to other pathogens, a laboratory diagnosis of B19 infection is required. A diagnostic protocol must consider both the type of pathology and the type of patient. In immunocompetent individuals serological and virological testing is complementary, while in immunocompromised patients viral detection is the diagnosis of choice. Viral detection methods are generally based, nowadays, on the direct detection of B19 genome in clinical specimens. B19 DNA is mainly detected by hybridizations assays and by the most sensitive PCR assays. Serological diagnosis of B19 infection is generally achieved by detection of IgM and IgG antibodies to the B19 structural proteins VP1 and VP2. IgM detection is most often performed by capture assays, both in EIA and RIA formats, IgG are mainly detected by indirect EIA and immunofluorescence tests.

Antibodies, Viral↗
PubMed2002

Endoscopic markers in adult coeliac disease.

BACKGROUND: Various endoscopic markers have been described in coeliac disease, particularly in the second part of the duodenum, with minor attention generally being paid to the duodenal bulb. AIMS: To evaluate, prospectively, the presence of all endoscopic markers in the bulb and the second part of the duodenum on a large series of patients submitted to endoscopy for duodenal biopsy. PATIENTS AND METHODS. A total of 367 consecutive patients, submitted to endoscopy with duodenal biopsy for various indications, were considered. Biopsies were graded as normal, with partial villous atrophy (mild, moderate, severe) or with subtotal villous atrophy. Endoscopic markers and corresponding locations evaluated were: micronodular pattern [bulb and descending duodenum], mosaic appearance (bulb and descending duodenum), scalloped folds (descending duodenum), reduced or absent folds (descending duodenum). RESULTS: In 78 patients, a diagnosis of untreated coeliac disease was made. Endoscopic markers were seen in 73/78 patients, with only a single sign present (bulb or descending duodenum) in 12 patients. In the remaining 289 patients, normal histology and normal endoscopic findings were observed, except in two patients with reduced folds. Sensitivity, specificity, positive and negative predictive values and diagnostic accuracy regarding all endoscopic markers were 93.6%, 99.3%, 97.3%, 98.3% and 98.1%, respectively CONCLUSIONS: This study confirms the usefulness of endoscopic markers in detecting coeliac disease, underlining the importance of evaluating also abnormalities in the bulb and endoscopic single signs; although endoscopy may not detect all cases of coeliac disease, the recognition of endoscopic markers allows the selection for biopsy of unsuspected patients submitted to endoscopy for non-specific symptoms.

Adolescent↗
PubMed2002

Analysis of B19 virus contamination in plasma pools for manufacturing, by using a competitive polymerase chain reaction assay.

BACKGROUND AND OBJECTIVES: The presence of B19 virus in blood poses a risk of transmission of the virus via blood or blood products. Screening processes for manufacturing should be aimed at achieving production plasma pools with B19 virus contamination levels below 104 genome equivalents/ml (geq/ml) in order to prevent transmission of infection through plasma derivatives. MATERIALS AND METHODS: The suitability of a competitor plasmid as an internal analytical standard for the detection of B19 virus in plasma pools was assessed by using a competitive polymerase chain reaction (PCR) assay. Seventy-five plasma pools, each consisting of 960 single donations, were analysed for B19 virus contamination following a lysis treatment. RESULTS: The amount of competitor plasmid in the competitive PCR assay established, with good accuracy, a threshold value for discrimination of the viral load in plasma pools. Analysis of samples from plasma pools showed that 12% of pools were contaminated with B19 virus at levels above the set threshold value. CONCLUSIONS: The competitive PCR assay developed proved to be effective for discrimination of the B19 virus contamination level in screening of plasma pools for manufacturing.

Blood Donors↗
PubMed2001

Detection of adeno-associated virus DNA in female genital samples by PCR-ELISA.

Adeno-associated viruses (AAV) are human parvoviruses that require helper function for their replication. Several studies have demonstrated that AAV DNA sequences can be found in the female genital tract but the incidence of infection seems very variable. A PCR-ELISA method detecting AAV DNA was developed for combining the specificity and the sensitivity of conventional PCR with an objective interpretation of the results. In the PCR-ELISA, a defined number of cells from cervical specimens were digested and amplified with concomitant digoxigenin labeling. Digoxigenin-labeled amplified products hybridized to a specific biotinylated probe were captured in streptavidin-coated microtiter wells by a biotin-streptavidin binding and were visualized by colorimetric immunoenzymatic reaction. PCR-ELISA was carried out in 110 cervical cytological specimens of women with or without the concomitant detectable presence of papillomavirus (HPV) DNA and the results were compared with those obtained by conventional PCR followed by dot blot hybridization. When compared to conventional PCR considered as reference standard, PCR-ELISA was found to be 98% sensitive and 96% specific. Out of the total 110 samples examined, 52.7% were positive for AAV DNA by both techniques, demonstrating a high prevalence of AAV infection in the uterine cervix. When analyzing samples with or without the presence of HPV DNA, 63.2 % of the samples were positive for HPV DNA and 41.5% of the samples were negative for HPV proved positive for AAV DNA by both PCR-ELISA and conventional PCR. Hence, PCR-ELISA, which can be completed in 1 day, proved to be a reliable method for an objective detection of AAV DNA in clinical samples. The present study showed a frequent infection of the cervical epithelium with AAV both in the presence and absence of HPV infection.

Cervix Uteri↗
PubMed2001

A system to enhance the sensitivity of digoxigenin-labelled probe: detection of B19 DNA in serum samples.

A highly sensitive dot-blot hybridisation assay for the routine screening of numerous samples is described, using parvovirus B19 as a model. Digoxigenin-labelled B19 DNA probe was constructed by PCR, hybrids were detected by an anti-digoxigenin monoclonal antibody followed by a second step, using anti-mouse antibodies conjugated to an alkaline phosphatase-dextran complex (EnVision, Dako) was carried out. The sensitivity of the assay was evaluated using both colourimetric and chemiluminescent substrates for the alkaline phosphatase and was compared with a dot-blot hybridisation assay using the digoxigenin-labelled probe and a standard detection system. With the colourimetric substrate, the EnVision system was able to detect 10 fg of B19 DNA, while with the chemiluminescent substrate the sensitivity increased by up to 2 fg (6 x 10(2) genome copies). This detection system was shown to increase the sensitivity of the assay compared to the standard colourimetric visualisation for the digoxigenin-labelled probe, which could detect 0.1 pg. On account of its sensitivity and specificity the dot-blot hybridisation assay together with the chemiluminescent substrate for the EnVision detection system was used to analyse 760 serum samples; the same sera were tested for B19 DNA with the standard colourimetric visualisation for the digoxigenin-labelled probe used routinely in the diagnostic laboratory.

DNA Probes↗
PubMed1999

Effect of Helicobacter pylori infection, age and epithelial cell turnover in a general population at high risk for gastric cancer.

BACKGROUND: H. pylori and age are two known risk factors for atrophic gastritis and high epithelial cell turnover may be an indicator for preneoplastic changes in the stomach. We searched for an association between H. pylori, age and gastritis in the general population together with the proliferative state into the antral mucosa. METHODS: We examined gastric biopsies from antrum and corpus of 117 consecutive volunteers which were endoscoped during a population study in San Marino. H. pylori status was determined by serum IgG antibodies, rapid urease test on biopsies and histology. Presence of gastritis and grading of inflammation, activity, intestinal metaplasia and atrophy were ascertained using Sydney System. On a subsample of 36 subjects without endoscopic lesions we performed an immunohistochemical study on gastric cell proliferation using PCNA. A computer-aided count was made on stained epithelial cells to evaluate labeling index. Statistical analysis was performed using chi 2 test and linear regression. RESULTS: Inflammatory infiltrate (both activity and mononuclear cells), (p < 0.0001) and intestinal metaplasia (p < 0.004) were significantly higher in H. pylori positive subjects. Atrophic gastritis was present in 82% H. pylori positive subjects vs 17.6% (p < 0.0001). Labeling Index was significantly higher in H. pylori positive subjects (p < 0.005) and it was correlated with inflammation and atrophy (p = 0.001). Elderly H. pylori negative subjects have a lower cell turnover (p = 0.006) but H. pylori infected subjects do not show any decrease of Labeling Index with age. CONCLUSIONS: In the general population of an area with high gastric cancer rate, H. pylori infection is associated with atrophic gastritis and with hyperproliferative gastric cell state. These conditions are present either in young and old age and increase the neoplastic risk of gastric mucosa.

Adult↗
PubMed1998

Epithelial-cell apoptosis and proliferation in Helicobacter pylori-related chronic gastritis.

BACKGROUND: Several studies have shown that Helicobacter pylori infection is associated with enhanced gastric epithelial-cell proliferation, which is thought to be involved in its apparent carcinogenicity. This hyperproliferation is believed to be related to the inflammatory effects of the bacterium. The role of Helicobacter pylori in gastric epithelial apoptosis, however, is less clear. AIM: We attempted to identify the effect of Helicobacter pylori infection on apoptosis in the gastric epithelium and its possible relation to epithelial-cell proliferation and mucosal inflammation. PATIENTS AND METHODS: We studied cell proliferation (via bromodeoxyuridine labelling), apoptosis (using in situ TdT-mediated dUTP-biotin nick end labelling of DNA strand breaks) and mononuclear and polymorphonuclear cell infiltrates (computer-assisted image analysis) in gastric antral biopsies obtained from 37 gastritis patients (20 Helicobacter pylori-positive, 17 Helicobacter pylori-negative). RESULTS: Helicobacter pylori-positives displayed significantly enhanced proliferation within the gastric epithelium that was positively correlated with both acute and chronic inflammatory-cell densities. Apoptotic indexes were similar in both groups and showed no correlation with any of the parameters under consideration. CONCLUSIONS: Enhanced epithelial cell proliferation and an altered distribution of cycling cells within the gastric glands are a common feature of chronic superficial gastritis caused by Helicobacter pylori. In vivo immunohistochemically detected apoptosis of gastric epithelial cells does not seem to be affected by Helicobacter pylori infection. Further study is needed to clarify the effect of this infection on programmed cell death within gastric glands.

Adult↗
PubMed1997

Population-based survey of hepatitis A virus infection in the Republic of San Marino.

In 1990-1991, the prevalence of antibodies to hepatitis A virus infection (anti-HAV) was assayed by the ELISA method among 1528 apparently healthy subjects, 20-85 years old in the Republic of San Marino. Subjects were selected from the list of residents by a random stratified sampling procedure with a proportional allocation by age, sex and district of residence. The overall anti-HAV prevalence was 64.7%; it increased from 28.6% in subjects 20-30 years old to 97% in those > 60 years (p < 0.01). No gender difference was observed. At the multivariate analysis age > 40 years (OR: 39.5; 95% CI: 12.4-126) and lowest level of schooling (OR: 1.8; 95% CI: 1.1-2.9), which is a good indirect indicator of socio-economic status, resulted both independent predictors of anti-HAV seropositivity. These findings reflect the improved sanitation standards in this area and indicate that the proportion of non-immune adults is increasing with a higher risk of symptomatic infection in the near future.

Adult↗
PubMed1997

Seroprevalence of hepatitis A virus and Helicobacter pylori infections in the general population of a developed European country (the San Marino study): evidence for similar pattern of spread.

OBJECTIVE: To evaluate the role of faecal-oral transmission in the spread of Helicobacter pylori. DESIGN: A cross-sectional comparison of the patterns of hepatitis A and H. pylori seropositivity. METHODS: At interview, blood samples and questionnaire data were collected from a random sample of 1528 healthy subjects aged 20-85 years from the Republic of San Marino. Serum samples from each subject were then tested for anti-H. pylori and anti-hepatitis A antibodies. RESULTS: Overall, 529 of 670 H. pylori-seropositive subjects (78.9%) and 460 of 858 H. pylori-seronegative subjects (53.6%) were hepatitis A seropositive (P<0.01; odds ratio=3.2; confidence interval 95%=2.6-4.1). This association remained after adjustment by a multiple logistic regression analysis for the confounding effect of age and length of schooling, as surrogate for socio-economic status (OR=2.0; CI 95%=1.3-3.3). The age-specific prevalence curves for H. pylori and hepatitis A infections showed a parallel increase by age, although to a lesser extent for H. pylori. CONCLUSION: These findings provide evidence that in the community studied H. pylori may have spread in a manner similar to that of hepatitis A.

Adult↗