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1.
J Antimicrob Chemother ; 70(6): 1858-64, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25700719

RESUMO

OBJECTIVES: Virological failure (VF) in patients on maraviroc-based treatment has been associated with altered HIV tropism and resistance to maraviroc. This multicentre study aimed to characterize VF in patients treated with maraviroc. METHODS: We analysed 27 patients whose treatment failed between 2008 and 2011. They had been screened for HIV tropism before maraviroc initiation using population-based V3 genotyping. HIV-1 tropism and resistance of R5 viruses to maraviroc at VF and at baseline were determined retrospectively using an ultrasensitive recombinant virus assay (RVA). RESULTS: Viruses from 27 patients given maraviroc on the basis of the R5 genotype were characterized at the time of treatment failure. The RVA indicated that 12 patients harboured CXCR4-using viruses and 15 (56%) had pure R5 viruses at failure. One-third of those harbouring CXCR4-using viruses (4/12) were infected with R5X4/X4 viruses according to the RVA before maraviroc initiation. We analysed the phenotypic resistance to maraviroc of four patients harbouring R5 viruses at failure; two harboured viruses whose maximum percentage inhibition was reduced by 65%-90%, while the other two were infected with susceptible viruses. All patients had effective concentrations of drugs. CONCLUSIONS: Half of the maraviroc-treated patients who experienced VF harboured CXCR4-using viruses at failure, one-third of them were detected by a phenotypic method before maraviroc initiation. Phenotypic assessment of R5 virus resistance to CCR5 antagonists at failure could help optimize antiretroviral therapy.


Assuntos
Antirretrovirais/uso terapêutico , Cicloexanos/uso terapêutico , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Triazóis/uso terapêutico , Tropismo Viral , Adulto , Idoso , Terapia Antirretroviral de Alta Atividade/métodos , Feminino , HIV-1/isolamento & purificação , Humanos , Masculino , Maraviroc , Pessoa de Meia-Idade , Estudos Retrospectivos , Falha de Tratamento , Carga Viral
2.
Emerg Infect Dis ; 20(8): 1343-6, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25061698

RESUMO

In France during 2012, human enterovirus 71 (EV-A71) subgenogroup C4 strains were detected in 4 children hospitalized for neonatal fever or meningitis. Phylogenetic analysis showed novel and independent EV-A71 introductions, presumably from China, and suggested circulation of C4 strains throughout France. This observation emphasizes the need for monitoring EV-A71 infections in Europe.


Assuntos
Enterovirus Humano A/genética , Infecções por Enterovirus/epidemiologia , Infecções por Enterovirus/virologia , Vigilância da População , Pré-Escolar , Enterovirus Humano A/classificação , Infecções por Enterovirus/história , França/epidemiologia , Genes Virais , História do Século XXI , Humanos , Recém-Nascido , Filogenia , Estudos Retrospectivos
3.
J Antimicrob Chemother ; 68(11): 2626-31, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23798669

RESUMO

OBJECTIVES: As recommended by the French ANRS programme for the surveillance of HIV-1 resistance, we estimated the prevalence of transmitted drug resistance-associated mutations (RAMs) in antiretroviral-naive, chronically HIV-1-infected patients. METHODS: RAMs were sought in samples from 661 newly diagnosed HIV-1-infected patients in 2010/11 at 36 HIV clinical care centres. Weighted analyses were used to derive representative estimates of the percentage of patients with RAMs. RESULTS: At patient inclusion, the prevalence of virus with protease (PR) or reverse transcriptase (RT) RAMs was 9.0% (95% CI 6.8%-11.2%). No integrase RAMs were observed. The prevalences of protease inhibitor, nucleoside RT inhibitor and non-nucleoside RT inhibitor RAMs were 1.8%, 6.2% and 2.4%, respectively. Resistance to one, two and three classes of antiretroviral agent was observed in 7.9%, 0.9% and 0.2% of patients, respectively. The frequency of RAMs was higher in patients infected with B compared with non-B subtype virus (11.9% versus 5.1%, P = 0.003). Baseline characteristics (gender, age, country of transmission, CD4 cell count and viral load) were not associated with the prevalence of transmitted RAMs. However, men having sex with men (MSM) were more frequently infected with resistant virus than were other transmission groups (12.5% versus 5.8%, P = 0.003). Compared with the 2006/07 survey, the overall prevalence of resistance remained stable. However, a significant decrease in the frequency of virus with PR RAMs was observed in 2010/11 compared with the 2006/07 survey (1.8% versus 5.0%, P = 0.003). CONCLUSIONS: In France in 2010/11, the global prevalence of transmitted drug-resistant variants was 9.0%, and the prevalence was stable compared with the 2006/07 survey. MSM and B subtype-infected patients are the groups with a higher prevalence of drug resistance.


Assuntos
Transmissão de Doença Infecciosa , Farmacorresistência Viral , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , HIV-1/efeitos dos fármacos , Adolescente , Adulto , Idoso , Feminino , França/epidemiologia , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Prevalência , RNA Viral/genética , Vigilância de Evento Sentinela , Adulto Jovem
4.
Int J Antimicrob Agents ; 42(1): 42-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23562640

RESUMO

This study aimed to identify factors associated with virological response (VR) to raltegravir (RAL)-containing regimens in 468 treatment-experienced but integrase inhibitor-naive HIV-1 patients receiving a RAL-containing regimen. VR was defined at Month 6 (M6) as HIV-1 RNA viral load (VL) <50 copies/mL. The impacts on VR of baseline integrase mutations, VL, CD4 count, genotypic sensitivity score for nucleoside reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors and protease inhibitors, and the number of new antiretrovirals used for the first time associated with RAL were investigated. For patients with VL >50 copies/mL at M6, integrase mutations selected were characterised. Median baseline VL was 4.2 log(10)copies/mL (IQR 3.3-4.9 log(10) copies/mL) and CD4 count was 219 cells/mm(3) (IQR 96-368 cells/mm(3)). At M6, 71% of patients were responders. In multivariate analysis, baseline VL and CD4 count and ≥ 2 new antiretrovirals among darunavir, etravirine, maraviroc and enfuvirtide were associated with VR to RAL. Neither HIV-1 subtype nor baseline integrase polymorphisms were associated with VR to RAL. Among 63 failing patients at M6, selection of ≥ 1 change in the integrase gene was observed in 49 (77.8%), and 27/63 (42.9%) were considered as RAL-associated resistance mutations. Factors independently associated with the occurrence of ≥ 1 RAL-associated resistance mutation were VL at failure >3 log(10) and having no new drugs associated with RAL. RAL showed great potency in treatment-experienced patients. The number of new drugs associated with RAL was an important factor associated with VR. HIV-1 subtype and baseline integrase polymorphisms do not influence the RAL VR.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Mutação de Sentido Incorreto , Pirrolidinonas/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Contagem de Linfócito CD4 , Estudos de Coortes , Feminino , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Humanos , Masculino , RNA Viral/sangue , Raltegravir Potássico , Falha de Tratamento , Carga Viral
5.
J Antimicrob Chemother ; 65(12): 2620-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20965891

RESUMO

OBJECTIVES: To estimate the prevalence of transmitted drug resistance mutations and non-B subtype circulation in antiretroviral-naive chronically HIV-1-infected patients in France. METHODS: Resistance mutations were sought in samples from 530 newly diagnosed HIV-1-infected patients from October 2006 to March 2007. Protease and reverse transcriptase mutations were identified from the 2007 Stanford Resistance Surveillance list. RESULTS: Reverse transcriptase and protease resistance mutations were determined in 466 patients with duration of seropositivity <5 years. 42% of patients were infected with non-B subtype strains (CRF02 18.3%). The overall prevalence of viruses with protease or reverse transcriptase mutations was 10.6% (95% confidence interval 6.7-16.3). The prevalence of protease inhibitor, nucleoside reverse transcriptase inhibitor and non-nucleoside reverse transcriptase inhibitor resistance-associated mutations was 4.7%, 5.8% and 2.8%, respectively. Frequency of resistance was not different in patients infected with B (9.5%) and non-B (CRF02 7.8% and other 11.2%) subtypes. Baseline characteristics such as gender, age, transmission group, country of transmission, disease stage, CD4 counts and viral load were not associated with the prevalence of transmitted drug resistance. CONCLUSIONS: In France in 2006/2007, the prevalence of transmitted drug-resistant variants was 10.6%. Prevalence of transmitted drug resistance was comparable in B and non-B subtypes. Prevalence of non-B subtypes is still rising.


Assuntos
Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral/genética , Infecções por HIV/transmissão , HIV-1/efeitos dos fármacos , Mutação , Inibidores da Transcriptase Reversa/farmacologia , Fármacos Anti-HIV/uso terapêutico , Doença Crônica , Feminino , França/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Protease de HIV/genética , Transcriptase Reversa do HIV/genética , Soropositividade para HIV/tratamento farmacológico , Soropositividade para HIV/epidemiologia , Soropositividade para HIV/transmissão , Soropositividade para HIV/virologia , HIV-1/classificação , HIV-1/enzimologia , HIV-1/genética , Humanos , Masculino , Prevalência , Inibidores da Transcriptase Reversa/uso terapêutico
6.
J Virol ; 84(19): 10139-47, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20631141

RESUMO

Mutations in the internal ribosome entry site (IRES) of hepatitis A virus (HAV) have been associated with enhanced in vitro replication and viral attenuation in animal models. To address the possible role of IRES variability in clinical presentation, IRES sequences were obtained from HAV isolates associated with benign (n = 8) or severe (n = 4) hepatitis. IRES activity was assessed using a bicistronic dual-luciferase expression system in adenocarcinoma (HeLa) and hepatoma (HuH7) cell lines. Activity was higher in HuH7 than in HeLa cells, except for an infrequently isolated genotype IIA strain. Though globally low, significant variation in IRES-dependent translation efficiency was observed between field isolates, reflecting the low but significant genetic variability of this region (94.2% +/- 0.5% nucleotide identity). No mutation was exclusive of benign or severe hepatitis, and variations in IRES activity were not associated with a clinical phenotype, indirectly supporting the preponderance of host factors in determining the clinical presentation.


Assuntos
Regiões 5' não Traduzidas/genética , Vírus da Hepatite A/genética , Vírus da Hepatite A/patogenicidade , Hepatite A/virologia , RNA Viral/genética , Doença Aguda , Adolescente , Adulto , Sequência de Bases , Linhagem Celular , Criança , Primers do DNA/genética , DNA Viral/genética , França , Variação Genética , Genótipo , Células HeLa , Vírus da Hepatite A/isolamento & purificação , Vírus da Hepatite A/fisiologia , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Conformação de Ácido Nucleico , Filogenia , Biossíntese de Proteínas , RNA Viral/química , Virulência/genética , Adulto Jovem
7.
J Clin Microbiol ; 48(9): 3306-15, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20592136

RESUMO

Three hepatitis A virus (HAV) genotypes, I, II, and III, divided into subtypes A and B, infect humans. Genotype I is the most frequently reported, while genotype II is hardly ever isolated, and its genetic diversity is unknown. From 2002 to 2007, a French epidemiological survey of HAV identified 6 IIA isolates, mostly from patients who did not travel abroad. The possible African origin of IIA strains was investigated by screening the 2008 mandatory notification records of HAV infection: 171 HAV strains from travelers to West Africa and Morocco were identified. Genotyping was performed by sequencing of the VP1/2A junction in 68 available sera. Entire P1 and 5' untranslated regions of IIA strains were compared to reference sequences of other genotypes. The screening retrieved 5 imported IIA isolates. An additional autochthonous case and 2 more African cases were identified in 2008 and 2009, respectively. A total of 14 IIA isolates (8 African and 6 autochthonous) were analyzed. IIA sequences presented lower nucleotide and amino acid variability than other genotypes. The highest variability was observed in the N-terminal region of VP1, while for other genotypes the highest variability was observed at the VP1/2A junction. Phylogenetic analysis identified 2 clusters, one gathering all African and two autochthonous cases and a second including only autochthonous isolates. In conclusion, most IIA strains isolated in France are imported by travelers returning from West Africa. However, the unexplained contamination mode of autochthonous cases suggests another, still to be discovered geographical origin or a French reservoir to be explored.


Assuntos
Vírus da Hepatite A Humana/classificação , Vírus da Hepatite A Humana/genética , Hepatite A/epidemiologia , Hepatite A/virologia , Regiões 5' não Traduzidas , Adulto , Análise por Conglomerados , França/epidemiologia , Genótipo , Vírus da Hepatite A Humana/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência , Viagem , Proteínas Estruturais Virais/genética
8.
Antimicrob Agents Chemother ; 54(8): 3335-40, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20530226

RESUMO

Genotypic algorithms for prediction of HIV-1 coreceptor usage need to be evaluated in a clinical setting. We aimed at studying (i) the correlation of genotypic prediction of coreceptor use in comparison with a phenotypic assay and (ii) the relationship between genotypic prediction of coreceptor use at baseline and the virological response (VR) to a therapy including maraviroc (MVC). Antiretroviral-experienced patients were included in the MVC Expanded Access Program if they had an R5 screening result with Trofile (Monogram Biosciences). V3 loop sequences were determined at screening, and coreceptor use was predicted using 13 genotypic algorithms or combinations of algorithms. Genotypic predictions were compared to Trofile; dual or mixed (D/M) variants were considered as X4 variants. Both genotypic and phenotypic results were obtained for 189 patients at screening, with 54 isolates scored as X4 or D/M and 135 scored as R5 with Trofile. The highest sensitivity (59.3%) for detection of X4 was obtained with the Geno2pheno algorithm, with a false-positive rate set up at 10% (Geno2pheno10). In the 112 patients receiving MVC, a plasma viral RNA load of <50 copies/ml was obtained in 68% of cases at month 6. In multivariate analysis, the prediction of the X4 genotype at baseline with the Geno2pheno10 algorithm including baseline viral load and CD4 nadir was independently associated with a worse VR at months 1 and 3. The baseline weighted genotypic sensitivity score was associated with VR at month 6. There were strong arguments in favor of using genotypic coreceptor use assays for determining which patients would respond to CCR5 antagonist.


Assuntos
Cicloexanos/uso terapêutico , Inibidores da Fusão de HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1/metabolismo , Receptores de HIV/genética , Triazóis/uso terapêutico , Tropismo , Adulto , Antagonistas dos Receptores CCR5 , Cicloexanos/farmacologia , Feminino , Genótipo , Proteína gp120 do Envelope de HIV , Inibidores da Fusão de HIV/farmacologia , Infecções por HIV/virologia , Protease de HIV/genética , Transcriptase Reversa do HIV/genética , HIV-1/efeitos dos fármacos , HIV-1/genética , HIV-1/fisiologia , Humanos , Masculino , Maraviroc , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fenótipo , Receptores CCR5/genética , Receptores CCR5/metabolismo , Receptores de HIV/metabolismo , Sensibilidade e Especificidade , Análise de Sequência de DNA , Resultado do Tratamento , Triazóis/farmacologia
9.
Liver Transpl ; 15(10): 1336-42, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19790146

RESUMO

The aim of this study was to evaluate the impact of an enfuvirtide-based antiretroviral (ARV) regimen on the management of immunosuppression and follow-up in hepatitis C virus (HCV)/hepatitis B virus (HBV)/human immunodeficiency virus (HIV)-coinfected liver transplant patients in comparison with a lopinavir/ritonavir-based ARV regimen. Tacrolimus and cyclosporine trough concentrations were determined at a steady state during 3 periods: after liver transplantation without ARV treatment (period 1), at the time of ARV reintroduction (period 2), and 2 to 3 months after liver transplantation (period 3). The findings for 22 HIV-coinfected patients were compared (18 with HCV and 4 with HBV); 11 patients were treated with enfuvirtide and were matched with 11 lopinavir/ritonavir-exposed patients. During period 1, tacrolimus and cyclosporine A doses were 8 and 600 mg/day, respectively, and the trough concentrations were within the therapeutic range in both groups. In period 2, the addition of lopinavir/ritonavir to the immunosuppressant regimen enabled a reduction in the dose of immunosuppressants required to maintain trough concentrations within the therapeutic range (to 0.3 mg/day for tacrolimus and 75 mg/day for cyclosporine). Immunosuppressant doses were not modified by the reintroduction of enfuvirtide, there being no change in the mean trough concentrations over the 3 periods. CD4 cell counts remained at about 200 cells/mm3. The HIV RNA viral load remained undetectable. Both groups displayed signs of mild cytolysis and cholestasis due to the recurrence of HCV, whereas no renal insufficiency was observed. Enfuvirtide is an attractive alternative to standard ARV therapy, facilitating the management of drug-drug interactions shortly after liver transplantation. Moreover, the lack of liver toxicity renders this drug valuable in the event of a severe HCV recurrence.


Assuntos
Antirretrovirais/uso terapêutico , Proteína gp41 do Envelope de HIV/uso terapêutico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Falência Hepática/complicações , Falência Hepática/terapia , Transplante de Fígado/métodos , Fragmentos de Peptídeos/uso terapêutico , Adulto , Ciclosporina/uso terapêutico , Relação Dose-Resposta a Droga , Enfuvirtida , Feminino , Humanos , Imunossupressores/uso terapêutico , Lopinavir , Masculino , Pessoa de Meia-Idade , Pirimidinonas/uso terapêutico , Ritonavir/uso terapêutico , Tacrolimo/uso terapêutico , Resultado do Tratamento
10.
J Clin Microbiol ; 47(5): 1536-42, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19321728

RESUMO

We assessed the feasibility of using dried serum spots (DSS) for the serological and molecular diagnosis of hepatitis A virus (HAV) infection. Sixty-eight sera spotted onto filter papers (Whatman International Ltd., United Kingdom) were used for detection of total anti-HAV antibodies, and 64 sera were used for detection of immunoglobulin M antibody to HAV. DSS were stored at 4 degrees C, room temperature, and 37 degrees C for 1, 2, and 4 weeks. Sensitivity and specificity of the serological assays were 100% regardless of temperature and storage duration. To assess the stability of HAV RNA, we performed qualitative and quantitative reverse transcription-PCRs (RT-PCRs) with human plasma spiked with serial dilutions of cultured HAV spotted on Flinders Technology Associates filter paper cards (Whatman International Ltd.). Filter papers were stored at room temperature and processed for RT-PCR assays. No reduction of viral load was observed after 5, 15, and 30 days of storage. The approximately 10-fold reduction of sensitivity from DSS was attributable to a smaller sample input in DSS samples. This method was further evaluated using 35 frozen sera. HAV RNA amplification showed 100% specificity and 92.3% sensitivity, and sequence analysis from DSS and sera provided identical results. HAV RNA can be accurately recovered from DSS for molecular epidemiology purposes, and we confirm the reliability of blotted samples in the serological diagnosis of HAV infection. The DSS method facilitates storage and shipment of samples from routine laboratories to reference centers for further investigations and large epidemiological studies.


Assuntos
Dessecação , Anticorpos Anti-Hepatite A/sangue , Vírus da Hepatite A/isolamento & purificação , Hepatite A/diagnóstico , Soro/virologia , Manejo de Espécimes/métodos , Humanos , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Análise de Sequência de DNA , Homologia de Sequência , Reino Unido
11.
Liver Transpl ; 14(9): 1309-12, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18756459

RESUMO

A 63-year-old woman treated with prednisone for sinusitis developed fulminant liver failure due to a clinically unsuspected primary varicella zoster virus infection. The diagnosis of herpetic hepatitis was made from a liver biopsy, and varicella zoster virus viremia was detected by polymerase chain reaction. She was treated successfully with transplantation and perioperative administration of acyclovir.


Assuntos
Varicela/complicações , Herpesvirus Humano 3/metabolismo , Falência Hepática Aguda/complicações , Falência Hepática Aguda/terapia , Transplante de Fígado/métodos , Aciclovir/uso terapêutico , Antivirais/uso terapêutico , Biópsia , Varicela/terapia , Feminino , Humanos , Fígado/virologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prednisona/efeitos adversos , Resultado do Tratamento
12.
Antimicrob Agents Chemother ; 52(4): 1545-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18227188

RESUMO

We determine phenotypic susceptibility of human immunodeficiency virus type 2 (HIV-2) isolates to amprenavir, atazanavir, darunavir, indinavir, lopinavir, nelfinavir, saquinavir, and tipranavir. Saquinavir, lopinavir, and darunavir are potent against wild-type HIV-2 isolates and should be preferred as first-line options for HIV-2-infected patients. Other protease inhibitors are less active against HIV-2 than against HIV-1.


Assuntos
Inibidores da Protease de HIV/farmacologia , HIV-2/classificação , HIV-2/efeitos dos fármacos , Darunavir , Protease de HIV/efeitos dos fármacos , HIV-2/enzimologia , Humanos , Concentração Inibidora 50 , Lopinavir , Testes de Sensibilidade Microbiana , Fenótipo , Pirimidinonas/farmacologia , Saquinavir/farmacologia , Sulfonamidas/farmacologia
13.
J Clin Virol ; 41(2): 129-33, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18069058

RESUMO

BACKGROUND AND OBJECTIVES: Enzyme-linked immunoassays (ELISA) are the most widely used anti-hepatitis C virus (HCV) screening tests but simple, instrument and electricity-free screening tests have been developed with results available in a few minutes. METHODS: The sensitivity of a rapid immuno-chromatographic assay for the detection of anti-HCV antibodies was evaluated on 421 HCV RNA-positive samples from chronic carriers and compared with ELISA method. RESULTS: The sensitivity of the ELISA method was 99.3% and the sensitivity of the rapid test was 95.5%. False negative results were independent of HCV genotype, but were associated with human immunodeficiency virus (HIV)-positive status. Among HIV-negative people, sensitivities of the rapid test and the EIA assay were 99.2% and 100%, respectively. Whereas among HIV-positive people, sensitivities were 77.5% and 96.3%. CONCLUSIONS: The immuno-chromatographic test is rapid and simple, and could be used along with rapid anti-HIV determination, in settings with limited facilities or when rapid results are required.


Assuntos
Cromatografia/métodos , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C Crônica/diagnóstico , Adulto , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Hepatite C Crônica/imunologia , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , Fatores de Tempo
14.
Gastroenterol Clin Biol ; 29(5): 573-6, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15980754

RESUMO

AIM: Diagnosis of acute hepatitis A virus (HAV) infection is classically based on the detection of HAV-IgM. Nevertheless, HAV-IgM can be positive for patients with polyclonal stimulation of their immune system (i.e. immune reactivation). To improve the diagnostic yield, an avidity test for HAV-IgG antibodies was developed and tested. METHODS: Avidity tests were performed in 128 sera: 11 selected samples from patients with past infection, 15 acute hepatitis A, 10 vaccinated subjects and 4 patients with immune reactivation as well as 84 HAV-IgM positive unselected sera, provided by routine laboratories. RESULTS: Patients with past infection had avidities over 70%, whereas avidities in patients with acute hepatitis A were below 50% during the first month following the onset of symptoms. As expected, patients with immune reactivation had avidities over 70% consistent with past infection. The results obtained for the 84 unselected sera allowed reconsidering the diagnosis of acute hepatitis A for nearly a third of patients. CONCLUSION: This test could improve the diagnosis of acute hepatitis A infection, particularly in elderly patients.


Assuntos
Afinidade de Anticorpos , Hepatite A/diagnóstico , Hepatite A/imunologia , Imunoglobulina G/imunologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Diagnóstico Diferencial , Feminino , Humanos , Imunoglobulina G/análise , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Testes Sorológicos
15.
J Clin Microbiol ; 42(11): 5121-4, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15528704

RESUMO

Diagnosis of acute hepatitis A virus (HAV) infection is based on the detection of HAV immunoglobulin M (IgM). However, IgM could be detected due to nonspecific polyclonal activation of the immune system. An avidity test for anti-HAV IgG was developed to distinguish acute infection, where low-avidity antibodies are detected, from immune reactivation. The assay was tested on 104 samples, including 11 sera from patients with past infection, 15 sera from patients with acute infection and 4 collected after recovery, 10 sera from vaccinated subjects, 4 sera from patients with suspected immune reactivation, and 60 unselected HAV-IgM positive sera, collected over 1 year in a routine laboratory. The avidity index (AI) was expressed as percentage. The results were provided as the mean +/- one standard deviation. Patients with a history of prior infection had AIs of >70% (mean, 86% +/- 10), whereas the mean AI was 36% +/- 16 during acute HAV infection (P < 0.001). Within the first month after the onset of hepatitis, avidity was either noncalculable due to a very low IgG titer or <50%. In patients with immune reactivation, avidity was >70% (88% +/- 10%), a finding consistent with a prior infection. Among the 60 unselected sera, 35 (58%) had a noncalculable or <50% avidity, and most of them had a detectable HAV RNA, confirming HAV infection. In contrast, 16 (27%) had an avidity of >70%, and none was reverse transcription-PCR positive, suggesting immune reactivation. These 16 patients were significantly older than the others (50 +/- 16 years versus 26 +/- 14 years). The new anti-HAV IgG avidity assay we developed could improve HAV infection diagnosis, particularly in elderly patients.


Assuntos
Afinidade de Anticorpos , Anticorpos Anti-Hepatite A/imunologia , Vírus da Hepatite A/imunologia , Hepatite A/diagnóstico , Imunoglobulina G/imunologia , Hepatite A/virologia , Anticorpos Anti-Hepatite A/sangue , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue
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