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T Santantonio

Publications and source records attributed to T Santantonio.

At least 19 recordsLinked to original sources
PubMed2006

Risk factors and outcome among a large patient cohort with community-acquired acute hepatitis C in Italy.

BACKGROUND: The epidemiology of acute hepatitis C has changed during the past decade in Western countries. Acute HCV infection has a high rate of chronicity, but it is unclear when patients with acute infection should be treated. METHODS: To evaluate current sources of hepatitis C virus (HCV) transmission in Italy and to assess the rate of and factors associated with chronic infection, we enrolled 214 consecutive patients with newly acquired hepatitis C during 1999-2004. The patients were from 12 health care centers throughout the country, and they were followed up for a mean (+/- SD) period of 14+/-15.8 months. Biochemical liver tests were performed, and HCV RNA levels were monitored. RESULTS: A total of 146 patients (68%) had symptomatic disease. The most common risk factors for acquiring hepatitis C that were reported were intravenous drug use and medical procedures. The proportion of subjects with spontaneous resolution of infection was 36%. The average timespan from disease onset to HCV RNA clearance was 71 days (range, 27-173 days). In fact, 58 (80%) of 73 patients with self-limiting hepatitis experienced HCV RNA clearance within 3 months of disease onset. Multiple logistic regression analyses showed that none of the variables considered (including asymptomatic disease) were associated with increased risk of developing chronic hepatitis C. CONCLUSIONS: These findings underscore the importance of medical procedures as risk factors in the current spread of HCV infection in Italy. Because nearly all patients with acute, self-limiting hepatitis C--both symptomatic and asymptomatic--have spontaneous viral clearance within 3 months of disease onset, it seems reasonable to start treatment after this time period ends to avoid costly and useless treatment.

Acute Disease↗
PubMed2005

Feasibility of vaccination in preventing secondary cases of hepatitis A virus infection.

Although the secondary transmission of hepatitis A virus (HAV) infection is preventable through vaccination, it is not known whether the vaccination of household contacts is feasible. To this end, we conducted a prospective cohort study among the household contacts, 40 years of age or less, of all persons infected with primary HAV infection (index cases) and admitted to eight hospitals in southern Italy within 7 days of onset. Household contacts were vaccinated, and serum samples were taken at vaccination and after 14 and 45 days. Secondary cases were defined as those with IgM seroconversion occurring at least two weeks after enrollment. Coprimary cases were those assumed to have had the same exposure as the index case. Susceptible cases were those who were negative for both IgG and IgM. A total of 495 household contacts participated (acceptance rate of 65%); 65% were vaccinated within 4 days of admission of the index case and 95% within 7 days. At enrollment, 196 (39.6%) household contacts were immune (IgG-positive serum). During follow-up, 19 (3.8%) were IgM-positive: 13 (2.6%) were coprimary cases and 6 (1.2%; 95% CI: 0.2-3.2) secondary cases (5 identified at 14 days from vaccination and 1 at 45 days). Of the 241 susceptible cases, 192 (79.7%) had developed IgG antibodies at 14 days and only 3 (1.2%) did not develop IgG antibodies at 45 days. The 65% acceptance rate and the finding that 95% of the participating household contacts were vaccinated within 7 days of the index case's hospitalization indicate that timely vaccination is indeed feasible. The necessity of returning for the collection of blood samples probably decreased the acceptance rate.

Adolescent↗
PubMed2004

Influence of chronic coinfection with hepatitis B and C virus on liver histology.

BACKGROUND: Few data are available on histological features of chronic hepatitis B (HBV) and C (HCV) virus coinfection. PATIENTS AND METHODS: We enrolled 142 consecutive patients with viral chronic hepatitis on their first liver biopsy: 27 HBsAg and anti-HCV positive (case BC group), 57 HBsAg positive and anti-HCV negative (control B group) and 58 anti-HCV positive, HBsAg/anti-HBs/anti-HBc negative (control C group). RESULTS: Patients in the case BC group showed serum HBVDNA (37% vs 71.9%, p < 0.005) and ground-glass hepatocytes (37% vs 66.7%, p < 0.01) less frequently than those in the control B group. The case BC group showed a lower prevalence of patients with detectable HCV-RNA than the control C group (60% vs 92.3%, p < 0.001) and a significantly higher fibrosis score (2.1 +/- 1.2 vs 1.5 +/- 1.1, p < 0.05). Of the 27 patients in the case BC group, 10 lacked serum HCV-RNA and showed significantly higher histological activity index (HAI) and fibrosis scores than those found in the 17 HCV-RNA positive (8.5 +/- 4.4 vs 5.4 +/- 2.4 for HAI, p < 0.05; 3.0 +/- 1.3 vs 1.69 +/- 1.0, p < 0.05 for fibrosis). CONCLUSION: Liver histology seems to be more severe in chronic coinfection with HBV and HCV than in single infection, particularly when HCV replication is impaired.

Adult↗
PubMed2004

Treatment of acute hepatitis C.

Progression from acute to chronic HCV infection occurs in 50% to 84% of cases. In light of the risk of developing chronic disease and the response rate to treatment once the disease is established, it is important to consider early treatment of acute HCV infection before it progresses to the chronic state. Several studies evaluated the efficacy of either alpha or beta IFN monotherapy in patients with acute hepatitis C, but nearly all trials are small and present great variability regarding timing, schedule, response definition and patient characteristics. To overcome these limits, IFN efficacy has been assessed by meta-analyses demonstrating that antiviral therapy during the acute phase of HCV significantly reduces evolution to chronic hepatitis. Accordingly, treatment of persons with acute hepatitis C is warranted. However, several issues remain to be addressed, such as the optimal regimen and timing. Recent data would indicate that induction with daily IFN is needed to optimize response and pegylated IFN monotherapy could be the best option. Combination therapy with ribavirin does not seem to increase the response rate but could be proposed as a second choice to patients non responding to IFN monotherapy. Delaying treatment by 2-3 months might allow the identification of cases who would spontaneously resolve without compromising efficacy. However, additional data are required to improve the selection of those patients at great risk of progressing to chronic disease, and also to establish the optimal treatment in terms of risk/benefit and cost-effectiveness ratio.

Acute Disease↗
PubMed2003

Re-treatment of patients with anti-HBe-positive chronic hepatitis B who relapsed after an initial course of lamivudine.

AIM: To evaluate the efficacy of a long-term course of lamivudine monotherapy in patients with anti-HBe-positive chronic hepatitis B who relapsed after the first course of either lamivudine/interferon (n = 16; Group 1) or lamivudine (n = 20; Group 2). METHODS: Biochemical and virological tests were performed every 3 months. At baseline and breakthrough, the region coding for the YMDD amino acid motif was sequenced. RESULTS: The length of re-treatment averaged 24 months. The virological response peaked at 6 months (94.4%), and declined to 66.7% and 50% at 12 and 24 months, respectively. The rates of breakthrough were 2.9%, 31.4% and 48.6% at 6, 12 and 24 months, respectively. By the second year, responders amounted to 62.5% and 40% in Groups 1 and 2, respectively (P = 0.10). The 18 responders at month 24 are still on therapy after 25-51 months of treatment: 14 still maintain a response, nine from Group 1 and five from Group 2. CONCLUSIONS: Re-treatment with lamivudine can control viral replication. This effect is maintained for the initial 12 months in two-thirds of patients, but afterwards the duration of response lessens due to the development of viral resistance.

Adult↗
PubMed2003

Natural course of acute hepatitis C: a long-term prospective study.

BACKGROUND: Acute hepatitis C has a high chronicity rate which appears to be significantly reduced by early antiviral treatment. However, it is unclear if all acutely infected patients should be treated, and when. In this prospective study, patients with a well-documented diagnosis of acute hepatitis C were evaluated to define the natural course, the rate of chronicity, and host and virus-related factors which might predict a self-limiting or chronic evolution requiring early antiviral treatment. METHODS: From 1995 to 2000, 40 consecutive patients with a community-acquired AHC were enrolled. Liver tests, anti-hepatitis C virus antibodies and hepatitis C virus RNA levels were monitored. Median follow-up was 35 months (range 12-68). RESULTS: A total of 24/40 patients had symptomatic disease including 20 with jaundice; 13/40 patients had prompt serum hepatitis C virus RNA clearance and ALT normalisation within 12 weeks; in 12/13 patients this pattern remained unchanged during follow-up. Overall, 27/40 patients remained hepatitis C virus RNA positive with fluctuating ALT levels. Older age and jaundice were predictive of resolution whereas there was no correlation with other host factors, viral genotype or viral load. CONCLUSIONS: Our data demonstrate that spontaneous resolution can occur in about 30% of AHC patients. This favourable outcome rarely occurs in patients with anicteric AHC or in those with jaundice but with persistent viremia for more than 12 weeks from onset; early antiviral treatment for these patients may avoid or reduce chronicity.

Acute Disease↗
PubMed2001

Treatment of acute hepatitis C with interferon alfa-2b.

BACKGROUND: In people who are infected with the hepatitis C virus (HCV) chronic infection often develops and is difficult to eradicate. We sought to determine whether treatment during the acute phase could prevent the development of chronic infection. METHODS: Between 1998 and 2001, we identified 44 patients throughout Germany who had acute hepatitis C. Patients received 5 million U of interferon alfa-2b subcutaneously daily for 4 weeks and then three times per week for another 20 weeks. Serum HCV RNA levels were measured before and during therapy and 24 weeks after the end of therapy. RESULTS: The mean age of the 44 patients was 36 years; 25 were women. Nine became infected with HCV through intravenous drug use, 14 through a needle-stick injury, 7 through medical procedures, and 10 through sexual contact; the mode of infection could not be determined in 4. The average time from infection to the first signs or symptoms of hepatitis was 54 days, and the average time from infection until the start of therapy was 89 days. At the end of both therapy and follow-up, 43 patients (98 percent) had undetectable levels of HCV RNA in serum and normal serum alanine aminotransferase levels. Levels of HCV RNA became undetectable after an average of 3.2 weeks of treatment. Therapy was well tolerated in all but one patient, who stopped therapy after 12 weeks because of side effects. CONCLUSIONS: Treatment of acute hepatitis C with interferon alfa-2b prevents chronic infection.

Acute Disease↗
PubMed2000

Vigorous peripheral blood cytotoxic T cell response during the acute phase of hepatitis C virus infection.

After infection by hepatitis C virus (HCV), a minority of patients develop acute symptomatic disease and some of them are able to clear the virus. In this study, we analyzed peripheral blood mononuclear cells from nine patients with acute symptomatic disease with respect to their cytotoxic T lymphocyte (CTL) response using a panel of HCV-derived peptides in a semiquantitative secondary in vitro culture system. We could detect early CTL responses in 67% of these patients. The CTL responses were directed against multiple viral epitopes, in particular within the structural (core 2-9, core 35-44, core 131-140, and core 178-187) and nonstructural regions of the virus (NS3 1073-1081, NS3 1406-1415, NS4 1807-1816, NS5 2252-2260, and NS5B 2794-2802). We compared the CTL responses displayed by recently and chronically infected HLA-A2-positive patients. Virus-specific CTLs were detectable in chronic carriers but the percentage of positive peptide-specific CTL responses was significantly higher in recently infected patients (P = 0.002). Follow-up of recently infected patients during subsequent disease development showed a significant decrease in the values and proportions of positive peptide-specific CTL responses (P = 0.002 and 0.013, respectively). Patients with limited viral replication exhibited significantly more vigorous early responses (P = 0.024). These data suggest a protective role for the early antiviral CTL response in HCV infection.

Acute Disease↗
PubMed2000

Association of hepatitis C virus-specific CD8+ T cells with viral clearance in acute hepatitis C.

CD8+ T lymphocytes play a major role in antiviral immune defense. Their significance for acute hepatitis C is unclear. Our aim was to correlate the CD8+ T cell response with the outcome of infection. Eighteen patients with acute hepatitis C and 19 normal donors were studied. Hepatitis C virus (HCV)-specific CD8+ T cells were identified in the enzyme-linked immunospot assay by their interferon-gamma (IFN-gamma) production after specific stimulation. The highest numbers of IFN-gamma-producing HCV-specific CD8+ T cells were found in patients with acute hepatitis C and a self-limited course of disease during the first 6 months after onset of disease, but these numbers dropped thereafter to undetectable levels. The differences in responsiveness between patients with self-limited disease versus patients with a chronic course were statistically significant (P<.001). Our data show that the number of IFN-gamma-producing HCV-specific CD8+ T cells during the first 6 months after onset of disease is associated with eradication of the HCV infection.

Acute Disease↗
PubMed2000

CD8+ T lymphocyte responses are induced during acute hepatitis C virus infection but are not sustained.

Cellular immune responses are likely to play a key role in determining the clinical outcome in acute infection with hepatitis C virus (HCV), but the dynamics of such responses and their relationship to viral clearance are poorly understood. In a previous study we have shown highly activated, multispecific cytotoxic T lymphocyte responses arising early and persisting in an individual who subsequently cleared the virus. In this study the HCV-specific CD8+ lymphocytes response has been similarly analyzed, using peptide-HLA class I tetramers, in a further nine individuals with documented acute HCV infection, six of whom failed to clear the virus. Significant populations of virus-specific CD8+ lymphocytes were detected at the peak of acute hepatic illness (maximally 3.5% of CD8+ lymphocytes). Frequencies were commonly lower than those seen previously and were generally not sustained. Early HCV-specific CD8+ lymphocytes showed an activated phenotype in all patients (CD38+ and HLA class II+), but this activation was short-lived. Failure to sustain sufficient numbers of activated virus-specific CD8+ lymphocytes may contribute to persistence of HCV.

Acute Disease↗
PubMed2000

Quantification of intrahepatic hepatitis B virus (HBV) DNA in patients with chronic HBV infection.

No data are available about the amount of hepatitis B virus (HBV) genomes in liver of patients with chronic HBV infection. The aim of this study was to quantify the intrahepatic HBV DNA in hepatitis B surface antigen (HBsAg)-positive patients with either active or suppressed viral replication and in HBsAg-negative subjects with occult HBV infection. We optimized the Roche "Amplicor HBV Monitor" kit for quantifying liver HBV DNA and analyzed hepatic DNA extracts and serum samples from 19 HBs-Ag-positive and 43 HBsAg-negative individuals. Eight of the HBsAg carriers had active HBV replication, and for 3 of them we analyzed samples obtained before and at the end of 1 year of lamivudine treatment. Five hepatitis Delta virus (HDV) coinfected patients and 6 healthy HBsAg carriers had inhibited HBV activity. Among the HBsAg-negative subjects 21 had occult HBV infection and 22 had no evidence of HBV infection. The median of HBV genomes per microgram of liver DNA milliliter of serum was 34,500 to 2,620,000 in patients with active viral replication, 20,000 to 3,900, 000 before and 10,000 to 2,800 at the end of therapy in lamivudine-treated individuals, 9,800 to 600 in HDV-infected individuals, and 7,450 to 17,400 in healthy HBsAg carriers. These data indicate that cases with suppressed HBV activity, despite the very low levels of viremia, maintain a relatively high amount of intrahepatic viral genomes. This virus reservoir is likely involved in HBV reactivation, which is usually observed after stopping lamivudine treatment. Finally, the analysis of cases with occult HBV infection showed that the assay we used was able to specifically detect and quantify as few as 100 copies of viral genomes per microgram of liver DNA.

Adult↗
PubMed2000

Long-term follow-up of patients with anti-HBe/HBV DNA-positive chronic hepatitis B treated for 12 months with lamivudine.

BACKGROUND/AIMS: Interferon alpha provides benefit in only a limited number of patients with chronic anti-HBe-positive hepatitis B. The aim of this study was to verify the long-term efficacy of lamivudine treatment of these patients and the incidence of lamivudine-resistant hepatitis B virus mutants. METHODS: Fifteen consecutive patients with chronic anti-HBe-positive hepatitis B were treated with lamivudine 100 mg once daily for 52 weeks. Levels of alanine aminotransferase, HBV DNA, hepatitis B surface antigen, and IgM antibodies to hepatitis B core antigen were monitored during therapy and 12-month follow up. The polymerase gene was amplified by polymerase chain reaction and the region coding for YMDD amino acid motif was directly sequenced. RESULTS: Only 2/15 patients (13%) had a sustained virological and biochemical response and improved histologically. Eleven out of 15 (74%) showed inhibition of viral replication and normalization of alanine aminotransferase levels during lamivudine treatment but relapsed 1-12 months after terminating therapy. In the two remaining patients (13%), HBV DNA initially became negative but reappeared in the serum after 24 weeks, and in both patients the emergence of YMDD mutants was demonstrated. CONCLUSIONS: Our data confirm the antiviral efficacy of lamivudine in anti-HBe-positive patients, but response to a 1-year course was only transient as the majority of patients relapsed after therapy withdrawal. The lack of a sustained effect and the emergence of lamivudine-resistant mutants suggest that therapy for chronic hepatitis B should be based on a combination of several therapeutic agents.

Adult↗
PubMed2000

Virologic and clinical expressions of reciprocal inhibitory effect of hepatitis B, C, and delta viruses in patients with chronic hepatitis.

We studied 648 hepatitis B surface antigen (HBsAg)- and/or anti-hepatitis C virus (HCV)-positive patients to evaluate the virologic and clinical characteristics of multiple hepatitis viral infection. We defined as Case B-C an HBsAg/anti-HCV positive patient and as Case b-C an anti-HCV/anti-HBc-positive, HBsAg/anti-HBs-negative patient. For each Case B-C we scheduled as Control-B an HBsAg positive and anti-HCV negative patient and as Control-C an HBsAg/anti-HBs/anti-hepatitis B core antigen (HBc)-negative and anti-HCV-positive patient. Control group C was used as the control also for Case group b-C. Serum HBV DNA by molecular hybridization was found more frequently in Control group B (54% of 161 patients) than in Case group B-C (35.7% of 84, P <.01). The prevalence of HBV wild type was similar in Case group B-C (14. 3%) and in Control group B (17.4%), whereas the e-minus strain was less frequent in Case group B-C (10.7% vs. 33%; P <.01). HBV DNA by polymerase chain reaction (PCR) was detected in 40.8% of 71 patients in Case group b-C. HCV RNA was detected more frequently in Control group C (90.7% of 130 patients) than in Case group B-C (65.2% of 69, P <.0001). Moderate or severe chronic hepatitis or cirrhosis were more frequent in Case group B-C (62.9% of 65 patients) than in Control group B (46.7% of 90, P <.05) or C (40.8% of 98, P <.005), and in Case group b-C (71.1% of 76) than in Control group C. Thus, in multiple hepatitis we observed a reciprocal inhibition of the viral genomes and a more severe liver disease. In Case group b-C, serum HBV DNA was frequent and the clinical presentation was severe.

Adult↗
PubMed1999

Virus-specific lymphokine production differs quantitatively but not qualitatively in acute and chronic hepatitis B infection.

Cytokines that are secreted as a response to viral antigen not only have direct antiviral properties but also crucially influence immune reactions determining the outcome of infection. As an advantageous alternative to the study of cytokines present in the supernatants of antigen-specific T cell clones and lines, we have used ELISPOT assays to determine the number of interferon-gamma (IFN-gamma)- and IL4-producing cells generated by peripheral blood mononuclear cells from patients with acute hepatitis B (AHB) and chronic hepatitis B (CHB) infection in response to HBcAg in a short-term culture (48 h). In response to HBcAg IFN-gamma was predominantly produced. In contrast to the results obtained in acute hepatitis B, the typical lymphokine pattern in CHB was characterized by a weak or absent antigen-specific IFN-gamma production. A predominance of IL-4-producing cells was not observed in either AHB or CHB. A significant number of IFN-gamma-producing cells was usually detectable during phases of viral elimination and the quality of the lymphokine response seemed to be epitope independent. Comparison of the results obtained in proliferation assays and ELISPOT assays clearly shows that lymphokine production upon stimulation with viral protein is totally independent of T cell proliferation and more sensitively reflects antiviral reactivity.

Acute Disease↗
PubMed1999

Recurrence of hepatitis C virus after loss of virus-specific CD4(+) T-cell response in acute hepatitis C.

BACKGROUND & AIMS: The prospective comparison of patients with acute hepatitis C virus (HCV) who spontaneously clear the virus with those who cannot achieve viral elimination and progress to chronic hepatitis offers the unique opportunity to analyze natural mechanisms of viral elimination. METHODS: We studied the HCV-specific CD4(+) T-cell response in 38 patients with acute HCV and correlated the clinical course with the antiviral immune response. The individual HCV-specific T-cell response was assessed in a proliferation assay ((3)H-thymidine uptake) and an enzyme-linked immunospot assay. RESULTS: Patients were classified according to their clinical course and pattern of CD4(+) T-cell responses in 3 categories: first, patients mounting a strong and sustained antiviral CD4(+)/Th1(+) T-cell response who cleared the virus (HCV RNA-negative; n = 20); second, patients who were unable to mount an HCV-specific CD4(+) T-cell response and developed chronic disease (n = 12); and third, patients who initially displayed a strong CD4(+) T-cell response and eliminated the virus (HCV PCR-negative) but subsequently lost this specific T-cell response (n = 6). The loss of the HCV-specific CD4(+) T-cell response was promptly followed by HCV recurrence. CONCLUSIONS: The results indicate that a virus-specific CD4(+)/Th1(+) T-cell response that eliminates the virus during the acute phase of disease has to be maintained permanently to achieve long-term control of the virus. The induction and/or maintenance of virus-specific CD4(+) T cells could represent a promising therapeutic approach in HCV infection.

Acute Disease↗
PubMed1999

Absence of mutations in the YMDD motif/B region of the hepatitis B virus polymerase in famciclovir therapy failure.

BACKGROUND/AIMS: Nucleoside analogues such as lamivudine and famciclovir are potent drugs for treatment of chronic hepatitis B virus infection. Breakthrough infections during lamivudine therapy are associated with mutations in the YMDD motif and putative B region of the HBV polymerase. This study investigated whether failure of famciclovir therapy is also associated with presence or emergence of particular mutations in the HBV polymerase. METHODS: We analyzed longitudinally the sequence of the priming and polymerase domain in seven patients with primary non-response to therapy and two patients with a breakthrough during therapy. Two patients who responded to therapy served as a control. RESULTS: The YMDD motif and the B region were conserved in all isolates. V-->I changes at position 555 just downstream of the YMDD motif were observed before and during therapy in a virus subpopulation of two patients with a primary non-response. In patients with a breakthrough, 378-V-->I and 424-N-->D mutations emerged in the N terminal part of the polymerase domain during follow-up. Lamivudine rescue therapy initiated in four patients, including a patient infected with YMDD(555-V-->I) variants, efficiently reduced viremia. CONCLUSIONS: These data indicate that failure of famciclovir therapy can occur independently of mutations in the YMDD motif or B region of the HBV polymerase and provide a rationale for rescue therapy with lamivudine.

2-Aminopurine↗
PubMed1999

Role of the specific T-cell response for clearance and control of hepatitis C virus.

T cells are believed to be the main players in antiviral defence. To investigate the role of the specific CD4+ T cell response for clearance and control of the hepatitis C virus we studied patients with acute hepatitis C (AHC) during the phase of spontaneous viral clearance and during follow up after elimination of the virus and resolution of disease. Symptomatic AHC has a self-limited course in 50% of patients, whereas the other half show virus persistence and develop chronic course of disease. Patients who were able to mount a vigorous, polyclonal, multispecific, TH1 lymphokine dominated CD4+ T-cell response showed viral clearance and a self-limited course of disease. In contrast, absence of this T-cell response in patients with AHC invariably led to viral persistence and chronic hepatitis. The characteristics of the T-cell response were as follows: it was mainly directed against nonstructural proteins of the virus, it was multispecific and demonstrated immunodominant epitopes, and the majority of T-cell clones established from our patients responded to a single peptide (NS3 amino acid 1248-1261) within the helicase region of HCV. Presentation of the peptide was HLA DR specific, the peptide showed promiscuous binding, and it had high binding affinity to 10 of the most common 13 HLA DR alleles, thus patients with diverse HLA DR backgrounds could mount an immune response. Furthermore, the epitope was conserved in 100% of 33 HCV strains published in databases. This strong initial CD4+ T-cell response is not sufficient for a definitive recovery from AHC, it has to be maintained to control the hepatitis C virus. Loss of the response after initial resolution of disease is followed by relapse. Even 20 years after an episode of self-limited AHC with elimination of HCV, we have observed a significant virus-specific CD4+ T-cell response. Our data indicate the decisive role of the virus-specific CD4+ T-cell response for clearance and control of HCV, and contribute to our understanding of immune mechanisms by which the host defends the HCV virus. This is a prerequisite for the development of new strategies to efficiently defend the virus by manipulating or modulating the immune response.

CD4-Positive T-Lymphocytes↗