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1.
J Med Virol ; 85(6): 996-1004, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23588725

RESUMO

While the selection of complex HBV drug-resistance patterns on therapeutic failure can compromise the efficacy of anti-HBV therapies, recent data show that patients failing treatment without drug-resistance have a rate of virological success close to drug-naive patients. The goal of this study is defining, in clinical practice, the burden of drug-resistance mutations in a cohort of patients treated with anti-HBV drugs. Prevalence and patterns of drug-resistance were analyzed by RT-sequencing in 204 patients infected chronically: 148 experiencing virological rebound (defined as an increase in serum HBV-DNA > 20 IU/ml after achieving virological success [HBV-DNA < 20 IU/ml]), and 56 null/partial responders (always detectable serum HBV-DNA [>20 IU/ml] within 48 weeks of therapy). The highest rate of drug-resistance was observed in patients experiencing virological rebound (prevalence, 79.1%). Conversely, almost half (46.4%) null/partial responders have no evidence of drug-resistance. The rate of drug-resistance was higher in patients treated with lamivudine (76.8% [109/142]) and telbivudine (83.3% [5/6]), followed by adefovir (62.5% [15/24]), and entecavir (52.2% [12/23]). Complex mutational patterns characterized by the co-presence of rtM204V/I-rtA181T/V (impairing the efficacy of all anti-HBV drugs) were detected in four patients (2.7%) with virological rebound. Drug-resistance is the main cause of failure to therapy in patients experiencing virological rebound, supporting the need of rapid switch to anti-HBV drugs with higher genetic barrier and potency (entecavir/tenofovir). Conversely, nearly half of null/partial responders shows no evidence of drug-resistance mutations, maintaining high chance of achieving therapeutic success with the same class of drug. In this setting, genotypic resistance may help in selecting patients still carrying wild-type viruses, that may take major benefits from antiviral treatment.


Assuntos
Antivirais/uso terapêutico , DNA Viral/antagonistas & inibidores , Farmacorresistência Viral/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Mutação , Adenina/análogos & derivados , Adenina/uso terapêutico , Adulto , Estudos de Coortes , Farmacorresistência Viral/genética , Feminino , Guanina/análogos & derivados , Guanina/uso terapêutico , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Humanos , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Organofosfonatos/uso terapêutico , Recidiva , Telbivudina , Timidina/análogos & derivados , Timidina/uso terapêutico , Resultado do Tratamento
2.
Antiviral Res ; 92(2): 382-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21920388

RESUMO

Presence of drug-resistance mutations in drug-naïve hepatitis B virus (HBV) infected patients can seriously compromise response to antiviral treatment. Therefore, our study was aimed at defining the prevalence of HBV drug-resistance in a population of 140 patients, all infected with HBV-D-genotype (the most common HBV-genotype in Eastern Europe, Mediterranean countries and Middle East) and naïve to antiviral therapy. HBV reverse-transcriptase (RT) region was sequenced and analyzed for 20 mutations, confirmed by in vitro studies as associated with resistance to nucleos(t)ide HBV-RT inhibitors (rtL80I/V-rtI169T-rtV173L-rtL180M-rtA181T/V/S-rtT184A/S/G/C-rtA194T-rtS202C/G/I-rtM204V/I-rtN236T-rtM250V). Amino acid changes at other six RT positions, potentially associated with resistance, were also analyzed (rtV84M-rtV191I-rtV207L-rtV214A-rtQ215S-rtI233V). Overall, only 2/140 (1.4%) patients carried primary drug-resistance mutations [rtA181V (0.7%), and rtA194T (0.7%)], while 3/140 (2.1%) patients harbored the secondary mutations rtV173L (1.4%) and rtL180M (0.7%). Additionally, five polymorphic mutations, with a suggested role in drug resistance, were detected [rtQ215S (12.8%), rtI233V (4.3%), rtV214A (3.6%), rtV191I (0.7%), rtV207L (0.7%)]. Notably, no YMDD mutations, namely rtM204V/I, were found. Taken together, the rate of important drug resistance mutations in naïve HBV D-genotype infected patients is today very low, and suggests the potential full efficacy of new-generation antiviral drugs used in first line therapy. Whether such low rate can be extrapolated to non HBV-D subtypes, requires a detailed investigation to be performed in a different cohort of patients.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/virologia , Mutação de Sentido Incorreto , Adulto , Substituição de Aminoácidos , Análise Mutacional de DNA , DNA Viral/química , DNA Viral/genética , Europa Oriental , Genótipo , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Humanos , Região do Mediterrâneo , Pessoa de Meia-Idade , Oriente Médio , Dados de Sequência Molecular , Prevalência , DNA Polimerase Dirigida por RNA/genética , Análise de Sequência de DNA , Proteínas Virais/genética
3.
Neuro Endocrinol Lett ; 22(1): 39-44, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11335878

RESUMO

OBJECTIVES: To clarify the relationship between interferon-alpha (IFN-alpha) therapy and autoimmune thyroiditis in chronic hepatitis C virus (HCV) infection, we investigated a selected number of patients without basal thyroid dysfunctions. MATERIALS AND METHODS: 130 patients (average age: 20-70), with chronic HCV infection and without basal clinical and laboratory signs of autoimmune thyroiditis were divided into two groups: IFN-alpha treated (A) and untreated (B) patients. Group A received IFN-alpha (three million U.I./3 times a week) for six months; group B was followed for the same period. Thyroid peroxidase and thyroglobulin autoantibodies were measured by radioimmunoassay; thyroid function was measured by radioimmunoassay (free thyroxine and triiodothyronine) and immunoradiometric assay (thyroid stimulating hormone). RESULTS: After a 6-month period, thyroid autoantibodies positivity was documented in 21.1% of group A and in 10.3% of group B patients, both statistically relevant (p<0.001 and p<0.011, respectively). The comparison between the two groups was not statistically relevant (p=0.142). CONCLUSIONS: Our study showed a prevalence of de novo thyroid autoimmunity in chronic HCV patients treated with IFN-alpha, confirming previous data in literature. The lack of a significant difference between treated and untreated patients strongly suggests that the anti-thyroid autoimmune response is linked to the HCV infection itself. Moreover, IFN-alpha therapy probably does not represent a risk factor in renewing the autoimmune processes of the thyroid gland. Thyroid function and autoantibodies must be systematically monitored in patients with HCV infection, especially in female and IFN-alpha treated population, not only to verify the possible thyroid abnormalities but also to rule out concomitant autoimmune diseases.


Assuntos
Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , Interferon-alfa/uso terapêutico , Tireoidite Autoimune/epidemiologia , Adulto , Idoso , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Comorbidade , Feminino , Seguimentos , Humanos , Incidência , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Tireoidite Autoimune/diagnóstico
4.
Panminerva Med ; 40(4): 269-72, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9973819

RESUMO

BACKGROUND: Aim of the study was to assess the correlation between clinical stage of HCV-related liver disease and viraemia to immune response to different viral antigens. METHODS: We considered 1330 patients with HCV chronic infection followed up from 6 months up to 6 years divided into two groups according to RIBA 3 (Abbott) response: Group I, 1231 patients with positivity for at least two bands (83 subjects with asymptomatic infection, 941 with chronic hepatitis, 201 with cirrhosis and 6 with HCC); Group II, 99 patients with positivity at only one band (45 with asymptomatic infection, 53 with chronic hepatitis and 1 cirrhotic). RESULTS: We noticed a major percentage of positive patients for at least three bands in more severe clinical forms (90% of chronic hepatitis or cirrhosis versus 60% of asymptomatics, p < 0.005, chi 2 test). Moreover we noticed a percentage increase of positivity for antibodies anti-c100 and anti-NS5 with the progression of liver damage, statistically significant differences between asymptomatics and patients with chronic forms. We also observed that viraemia is related neither to clinical stage nor to different reactivity to RIBA 3, albeit viraemia is usually detected more frequently among patients with liver damage, but unrelated to different reactivities. CONCLUSIONS: Our results show a clear correlation between number of reactivities towards HCV proteins and progression of liver damage, pointing out that immune response plays a direct role in the long-term outcome of HCV infection.


Assuntos
Anticorpos Anti-Hepatite C/sangue , Antígenos da Hepatite C/imunologia , Hepatite C Crônica/imunologia , Hepatite C Crônica/patologia , Idoso , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/virologia , Progressão da Doença , Feminino , Anticorpos Anti-Hepatite C/biossíntese , Antígenos da Hepatite C/metabolismo , Hepatite C Crônica/sangue , Humanos , Immunoblotting , Cirrose Hepática/imunologia , Cirrose Hepática/virologia , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Kit de Reagentes para Diagnóstico , Viremia/sangue , Viremia/imunologia , Viremia/virologia
5.
Clin Diagn Virol ; 4(4): 293-9, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15566850

RESUMO

Patients with hepatitis C virus (HCV) infection may have different patterns of antibody response to various structural and non-structural viral antigens. We have correlated the serological patterns to the clinical features of chronic infection and to viral replication in 68 HCV-Ab-positive patients with chronic liver disease at different stages (19 with cirrhosis-hepatocellular carcinoma, 38 with chronic active hepatitis and 11 with chronic persistent hepatitis). Serum samples from each patient were assayed for HCV-IgM by enzyme immunoassay and for HCV-RNA by the polymerase chain reaction using primer sets derived from the 5'-non-coding region. The prevalence of HCV-IgM was high (54 patients (79.4%)) and the study showed a good correlation between high values of anti-HCV-IgM and the presence of HCV-RNA in serum, since HCV-RNA was detected in 35 of the 54 IgM-positive patients (64.8%) and notably in 19 of the 20 subjects with high levels of specific IgM. Conversely, all the 35 sera containing HCV-RNA were also reactive for HCV-IgM, while none of the HCV-IgM-negative sera was HCV-RNA reactive. Positivity rates for both HCV-RNA and IgM anti-HCV were higher in the more advanced stages of disease; thus, the clinical pattern of HCV chronic hepatitis seems to be strictly related to the serological pattern and the presence of HCV-RNA.

6.
Arch Virol Suppl ; 4: 347-8, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1333331

RESUMO

The presence of anti-HCV antibodies was investigated in sera from a total of 123 inhabitants of two Tanzanian villages. In one of the villages, 72.2% of the sera and in the other village, 82.6% of the sera were found to be anti-HCV positive. These values are dramatically higher than other reported prevalences, whereby cross-reactivity between HCV and Flaviviruses as well as possible transmission by arthropod vectors cannot be ruled out.


Assuntos
Hepacivirus/imunologia , Anticorpos Anti-Hepatite/sangue , Adulto , Criança , Feminino , Humanos , Masculino , Tanzânia/epidemiologia
7.
Riv Eur Sci Med Farmacol ; 12(2): 135-9, 1990 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-2080311

RESUMO

Eleven hemodialysis patients (9 M, 2 F, aged 65 +/- 20 yrs) (Group A) were treated with thymopentin (TP-5) 50 mg as adjuvant therapy to HB vaccination, with 3 weekly administrations, the week before and the two following the first dose of Pasteur vaccine, 5 micrograms. The percentage of patients developing a sufficient antibody titer (20 mUI/ml) after 4 vaccine doses was not statistically different from that obtained among control groups B and C. The age- and sex- matched controls received the same vaccine schedule without adjuvant. The percentages were as follows: Group A 54.5%, Group B 63.6%, Group C 60%. No local or systemic side effects were encountered after the TP-5 administration. The authors suggest that a short TP-5 treatment as an adjuvant therapy to HB vaccination is not effective in patients maintained on hemodialysis.


Assuntos
Adjuvantes Imunológicos , Hepatite B/prevenção & controle , Diálise Renal , Timopentina/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vacinação
8.
Boll Ist Sieroter Milan ; 68(3): 271-6, 1989.
Artigo em Italiano | MEDLINE | ID: mdl-2491436

RESUMO

Twenty-four episodes of bacterial infections were identified over a 18 month period in 11 patients (8 with acquired immunodeficiency syndrome and 3 with AIDS related complex). Eight of the 11 infected patients were drug abusers and 3 homosexual people. Nosocomial bacterial infections were common in patients with AIDS and had high fatality rates. Gram-negative bacteria resulted the most common micro-organisms (E.coli, Proteus, Enterobacter, Serratia, Klebsiella). The Aztreonam treatment was very useful in providing bacteria eradication. Gram-positive bacteria as Staphylococcus from a sepsis and Enterococcus from a cystopyelitis were eradicated by B-lactam antibiotics. Common micro-organism are frequent in patients affected by LAS/ARC or AIDS and they negatively interfere with the disease outcome.


Assuntos
Complexo Relacionado com a AIDS/complicações , Síndrome da Imunodeficiência Adquirida/complicações , Infecções Bacterianas/complicações , Infecções Oportunistas/complicações , Complexo Relacionado com a AIDS/microbiologia , Síndrome da Imunodeficiência Adquirida/microbiologia , Adulto , Infecções Bacterianas/tratamento farmacológico , Suscetibilidade a Doenças , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Micoses/complicações , Infecções Oportunistas/tratamento farmacológico
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