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1.
Am J Clin Pathol ; 140(3): 403-9, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23955460

RESUMEN

OBJECTIVES: To correlate human herpesvirus 6 (HHV-6) viral load with pathologic features in graft acute hepatitis of unknown origin. METHODS: Liver frozen samples from 26 patients with graft hepatitis of unknown origin were available for HHV-6 DNA quantification. RESULTS: In 10 (38.5%) of 26 liver samples, HHV-6 DNA was detectable, with a median viral load of 3.84 log10 copies/106 cells. Confluent periportal necrosis was observed in 4 of 10 patients and associated with high viral load. These 4 patients responded to antiviral therapy. Mild unspecific hepatitis was observed in 4 patients with low intragraft viral load and in 2 patients with high viral load in a context of deep immunosuppression. Patients with HHV-6-negative graft hepatitis disclosed lobular necrotico-inflammatory activity without periportal necrosis. CONCLUSIONS: Our study provides data supporting the pathogenic role of HHV-6 for liver allografts. The presence of confluent periportal necrosis could be a clue for prompt diagnosis of HHV-6-induced graft hepatitis.


Asunto(s)
Hepatitis/patología , Herpesvirus Humano 6/aislamiento & purificación , Trasplante de Hígado/patología , Hígado/patología , Infecciones por Roseolovirus/patología , Adolescente , Adulto , ADN Viral , Femenino , Hepatitis/virología , Humanos , Hígado/virología , Masculino , Persona de Mediana Edad , Infecciones por Roseolovirus/virología , Carga Viral
2.
J Clin Microbiol ; 48(9): 3306-15, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20592136

RESUMEN

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.


Asunto(s)
Virus de la Hepatitis A Humana/clasificación , Virus de la Hepatitis A Humana/genética , Hepatitis A/epidemiología , Hepatitis A/virología , Regiones no Traducidas 5' , Adulto , Análisis por Conglomerados , Francia/epidemiología , Genotipo , Virus de la Hepatitis A Humana/aislamiento & purificación , Humanos , Persona de Mediana Edad , Epidemiología Molecular , Datos de Secuencia Molecular , Filogenia , ARN Viral/genética , Análisis de Secuencia de ADN , Homología de Secuencia , Viaje , Proteínas Estructurales Virales/genética
3.
J Virol ; 84(19): 10139-47, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20631141

RESUMEN

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.


Asunto(s)
Regiones no Traducidas 5'/genética , Virus de la Hepatitis A/genética , Virus de la Hepatitis A/patogenicidad , Hepatitis A/virología , ARN Viral/genética , Enfermedad Aguda , Adolescente , Adulto , Secuencia de Bases , Línea Celular , Niño , Cartilla de ADN/genética , ADN Viral/genética , Francia , Variación Genética , Genotipo , Células HeLa , Virus de la Hepatitis A/aislamiento & purificación , Virus de la Hepatitis A/fisiología , Humanos , Persona de Mediana Edad , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Mutación , Conformación de Ácido Nucleico , Filogenia , Biosíntesis de Proteínas , ARN Viral/química , Virulencia/genética , Adulto Joven
6.
Trans R Soc Trop Med Hyg ; 104(7): 475-83, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20378138

RESUMEN

There is little information on the diverse infectious causes of jaundice and hepatitis in the Asiatic tropics. Serology (hepatitis A, B, C and E, leptospirosis, dengue, rickettsia), antigen tests (dengue), PCR assays (hepatitis A, C and E) and blood cultures (septicaemia) were performed on samples from 392 patients admitted with jaundice or raised transaminases (> or =x3) to Mahosot Hospital, Vientiane, Laos over 3 years. Conservative definitions suggested diagnoses of dengue (8.4%), rickettsioses (7.3%), leptospirosis (6.8%), hepatitis B (4.9%), hepatitis C (4.9%), community-acquired septicaemia (3.3%) and hepatitis E (1.6%). Although anti-hepatitis A virus (HAV) IgM antibody results suggested that 35.8% of patients had acute HAV infections, anti-HAV IgG antibody avidity and HAV PCR suggested that 82% had polyclonal activation and not acute HAV infections. Scrub typhus, murine typhus or leptospirosis were present in 12.8% of patients and were associated with meningism and relatively low AST and ALT elevation. These patients would be expected to respond to empirical doxycycline therapy which, in the absence of virological diagnosis and treatment, may be an appropriate cost-effective intervention in Lao patients with jaundice/hepatitis.


Asunto(s)
Hepatitis Viral Humana/etiología , Ictericia/microbiología , Adolescente , Adulto , Niño , Preescolar , Infecciones Comunitarias Adquiridas/diagnóstico , Dengue/diagnóstico , Femenino , Fiebre/microbiología , Hepatitis Viral Humana/diagnóstico , Hospitalización , Humanos , Lactante , Recién Nacido , Ictericia/virología , Laos , Leptospirosis/diagnóstico , Masculino , Persona de Mediana Edad , ARN Viral/aislamiento & purificación , Infecciones por Rickettsia/diagnóstico , Tifus por Ácaros/diagnóstico , Pruebas Serológicas/métodos , Tifus Endémico Transmitido por Pulgas/diagnóstico , Adulto Joven
7.
J Hepatol ; 51(6): 1000-9, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19833404

RESUMEN

BACKGROUND/AIMS: Liver transplantation (LT) in immune-suppressed human immunodeficiency virus (HIV) and hepatitis C virus (HCV) coinfected patients is feasible but raises questions regarding the severity of HCV recurrence on the liver graft and preservation of immune function. We investigated whether LT is deleterious to the immune system. METHODS: Fourteen HIV-HCV coinfected patients (HIV viral load [VL] <50 copies/ml; median CD4 count of 276/mm(3) pretransplantation) were grafted for HCV-cirrhosis and followed over 2 years. Nine patients received anti-HCV therapy post-transplantation. HCV and HIV VLs and degree of acute and chronic hepatitis were monitored. Peripheral blood T-cell phenotypes and interferon-gamma (IFN-gamma) immune responses against opportunistic pathogens, HCV, and HIV-1 p24 were evaluated. RESULTS: Median HCV VLs, CD4 counts, T-cell subsets, and IFN-gamma-producing T-cell frequencies against opportunistic pathogens and HIV-1 p24 did not change over time. HCV-specific T cells were observed ex vivo in two patients pretransplantation and in two others post-transplantation. HCV-specific in vitro amplification enabled the detection of HCV-specific IFN-gamma-producing responses in three further patients post-transplantation. Anti-HCV responses were observed independently of anti-HCV therapy and were undetectable in patients with severe hepatitis or liver fibrosis. CONCLUSIONS: These results demonstrate that LT in HIV-HCV coinfected patients is not deleterious to the immune system and does not alter immune responses directed against HCV, HIV, or opportunistic pathogens.


Asunto(s)
Infecciones por VIH/complicaciones , Infecciones por VIH/inmunología , Anticuerpos contra la Hepatitis C/biosíntesis , Hepatitis C/complicaciones , Hepatitis C/inmunología , Cirrosis Hepática/inmunología , Cirrosis Hepática/cirugía , Trasplante de Hígado/inmunología , Infecciones Oportunistas Relacionadas con el SIDA/inmunología , Adulto , Recuento de Linfocito CD4 , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/cirugía , Femenino , Proteína p24 del Núcleo del VIH/inmunología , Hepatitis C/virología , Humanos , Tolerancia Inmunológica , Técnicas In Vitro , Interferón gamma/biosíntesis , Cirrosis Hepática/etiología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Subgrupos de Linfocitos T/inmunología , Carga Viral/inmunología
8.
J Clin Microbiol ; 47(5): 1536-42, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19321728

RESUMEN

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.


Asunto(s)
Desecación , Anticuerpos de Hepatitis A/sangre , Virus de la Hepatitis A/aislamiento & purificación , Hepatitis A/diagnóstico , Suero/virología , Manejo de Especímenes/métodos , Humanos , Datos de Secuencia Molecular , Filogenia , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad , Análisis de Secuencia de ADN , Homología de Secuencia , Reino Unido
9.
Liver Transpl ; 14(9): 1309-12, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18756459

RESUMEN

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.


Asunto(s)
Varicela/complicaciones , Herpesvirus Humano 3/metabolismo , Fallo Hepático Agudo/complicaciones , Fallo Hepático Agudo/terapia , Trasplante de Hígado/métodos , Aciclovir/uso terapéutico , Antivirales/uso terapéutico , Biopsia , Varicela/terapia , Femenino , Humanos , Hígado/virología , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Prednisona/efectos adversos , Resultado del Tratamiento
10.
Gastroenterology ; 134(7): 1890-9; quiz 2155, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18424269

RESUMEN

BACKGROUND & AIMS: Hepatitis B virus (HBV) recurrence after orthotopic liver transplantation (OLT) is significantly reduced by prophylaxis with hyperimmune antibody to hepatitis B surface antigen (anti-HBs) globulins (HBIG) and antiviral drugs. The role of hepatocellular carcinoma (HCC) in HBV recurrence remains unclear. We investigated the association between HCC pre-OLT and HBV recurrence post-OLT. METHODS: We studied 99 hepatitis B surface antigen-positive patients who underwent OLT for cirrhosis. The median follow-up period was 43 months. All patients received HBIG, and 51 also received lamivudine and/or adefovir. Of these 99 patients, 31 had HCC before OLT. Total HBV DNA and covalently closed circular (ccc)-DNA were measured in tumor and nontumor tissues from the explanted livers of 16 of these 31 HCC patients and, also, in a context of tumor recurrence, in 3 patients who developed HBV/HCC recurrence. RESULTS: Fourteen patients (14.1%) developed HBV recurrence within a median period of 15 months post-OLT. HCC at OLT, a pre-OLT HBV DNA viral load > or = 100,000 copies/mL, and HBIG monoprophylaxis were independently associated with HBV recurrence post-OLT. Eleven out of the 31 patients with HCC at OLT presented with HBV recurrence and 3 out of the 68 patients without HCC had HBV recurrence (P < .0001). HBV recurrence was more frequent in patients who developed HCC recurrence (7/8 patients, 87.5%) than in those who did not (4/23 patients, 17.4%) (P < .0001). In the 16 explanted livers, cccDNA was detectable in HCC cells in 11 and in nontumor cells in 12. cccDNA was detected in a context of HCC recurrence in 2 of the 3 patients tested who developed HBV/HCC recurrence. CONCLUSIONS: The associations of HCC pre-OLT, and HCC recurrence with HBV recurrence post-OLT, and the detection of HBV DNA and cccDNA in HCC suggest that HBV replication in tumor cells may contribute to HBV recurrence post-OLT.


Asunto(s)
Carcinoma Hepatocelular/virología , Virus de la Hepatitis B , Hepatitis B/etiología , Cirrosis Hepática/virología , Neoplasias Hepáticas/virología , Trasplante de Hígado , Adenina/análogos & derivados , Adenina/uso terapéutico , Adolescente , Adulto , Anciano , Antivirales/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/cirugía , ADN Circular/análisis , ADN Viral/análisis , Femenino , Estudios de Seguimiento , Hepatitis B/complicaciones , Hepatitis B/diagnóstico , Hepatitis B/tratamiento farmacológico , Hepatitis B/cirugía , Antígenos de Superficie de la Hepatitis B/análisis , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/crecimiento & desarrollo , Virus de la Hepatitis B/inmunología , Humanos , Inmunoglobulinas/uso terapéutico , Inmunohistoquímica , Lamivudine/uso terapéutico , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/cirugía , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Organofosfonatos/uso terapéutico , Reacción en Cadena de la Polimerasa , Medición de Riesgo , Factores de Riesgo , Prevención Secundaria , Análisis de Secuencia de ADN , Factores de Tiempo , Resultado del Tratamiento , Carga Viral , Replicación Viral
11.
J Clin Virol ; 41(2): 129-33, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18069058

RESUMEN

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.


Asunto(s)
Cromatografía/métodos , Hepacivirus/inmunología , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C Crónica/diagnóstico , Adulto , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Juego de Reactivos para Diagnóstico , Sensibilidad y Especificidad , Factores de Tiempo
12.
J Infect Dis ; 196(8): 1163-6, 2007 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-17955434

RESUMEN

The Kaposi sarcoma-associated herpesvirus (KSHV)-DNA level was determined in samples from 71 patients with Kaposi sarcoma (KS), 28 patients with multicentric Castleman disease (MCD), and 8 patients with primary effusion lymphoma (PEL). KSHV-DNA levels were higher in patients with active KS or MCD than in those with KS or MCD in remission. Among patients with active disease, the highest KSHV-DNA levels were observed in effusion fluid samples from patients with PEL (7.2 log(10) copies/150,000 cells), followed by blood samples from patients with MCD and PEL (4.86 and 3.83 log(10) copies/150,000 cells, respectively), and the lowest levels were observed in blood samples from patients with KS (2.63 log(10) copies/150,000 cells). Determining the KSHV-DNA level may be useful in diagnosing KSHV-associated disease and for following up patients with KS when the development of MCD or PEL is suspected.


Asunto(s)
Enfermedad de Castleman/virología , ADN Viral/sangre , Herpesvirus Humano 8/genética , Linfoma/virología , Sarcoma de Kaposi/virología , Carga Viral , Adulto , Anciano , Anciano de 80 o más Años , Líquido Ascítico/virología , Recuento de Linfocito CD4 , Enfermedad de Castleman/complicaciones , Femenino , Infecciones por VIH/complicaciones , Herpesvirus Humano 8/patogenicidad , Humanos , Linfoma/complicaciones , Masculino , Persona de Mediana Edad , Derrame Pleural/virología , Estudios Retrospectivos , Sarcoma de Kaposi/complicaciones
13.
Antivir Ther ; 12(8): 1255-63, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18240865

RESUMEN

BACKGROUND: Understanding the prevalence of potential antigenic variation of the hepatitis B virus (HBV) surface antigen (HBsAg) is fundamental for assay design and to future changes in vaccine formulation. In this study, the nature and frequency of HBsAg polymorphisms occurring in France in chronic carriers and in newly diagnosed patients were determined. We focused on variations in the major hydrophilic region (MHR), the central core of HBsAg known to be exposed on the surface and involved in antibody binding. METHODS: Two patient groups were identified: 51 chronic HBV carriers followed at our institution for > 1 year; and 129 newly diagnosed patients (63 of whom had a first HBsAg-positive result at our hospital laboratory and 66 a first positive result in a private laboratory). DNA sequences of HBsAg were obtained from these 180 patients and compared with consensus sequences built with 168 full-length HBV sequences imported from GenBank. Polymorphisms of the MHR of HBsAg were analysed with the Mutation Master Software. Literature review and BLOSUM scores were used to define potentially altered antigenicity. RESULTS: The global frequency of MHR variants was 27.8%. Occurrence of MHR variants was independent of viral load, HBeAg status and sex, but was associated with the chronic carriers' group, advancing age, the presence of antibodies to HBsAg, immunoprophylaxis administration, antiviral treatment and genotypic resistance to antivirals. In multivariate analysis, the independent variables associated with MHR variants were advancing age and the presence of genotypic resistance to nucleoside or nucleotide analogues. CONCLUSION: Most MHR variants emerge with longer disease duration and upon indirect selective pressure. Variation of the MHR may serve to restore virus replication of resistant strains. Combined envelope and polymerase variants could impair diagnostic assays and limit treatment alternatives.


Asunto(s)
Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Hepatitis B/virología , Factores de Edad , Secuencia de Aminoácidos , Portador Sano , Farmacorresistencia Viral/genética , Femenino , Francia , Hepatitis B/sangre , Hepatitis B/tratamiento farmacológico , Anticuerpos contra la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/inmunología , Virus de la Hepatitis B/efectos de los fármacos , Hepatitis B Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Nucleósidos/farmacología , Nucleótidos/farmacología , Polimorfismo Genético , Alineación de Secuencia , Carga Viral
14.
J Clin Microbiol ; 44(7): 2321-6, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16825343

RESUMEN

Mutations in hepatitis B virus surface antigen (HBsAg) involving amino acid substitution within the immunodominant "a" determinant may affect the performance of commercial HBsAg assays. The performances of four HBsAg assays that recently received Conformité Européene marking, Advia Centaur HBsAg (Bayer), Monolisa HBsAg Ultra (Bio-Rad), Liaison HBsAg (Dia Sorin), and Vidas HBsAg Ultra (bioMérieux), were compared with that of the routinely used HBsAg assay AxSYM HBsAg V2 (Abbott). Assays were evaluated for (i) analytical sensitivity performance with a national reference HBsAg panel (including 10 samples with calibrated HBsAg concentrations from 0.04 to 2.24 ng/ml) and (ii) the detection of HBsAg mutants by studying a panel of 35 HBsAg mutants (23 collected from patients and 12 recombinant mutants). The limits of detection of these assays were <0.15 ng/ml (from 0.089 to 0.121 ng/ml). The sensitivity performances for mutant virus detection varied, ranging from 37.1% to 91.4%. The lack of detection of these mutants by commercial assays was probably due to the epitope recognition of the anti-HBs assay reagents in the capture phase and in the conjugates. The prevalence and clinical impact of HBsAg mutants are under investigation. However, the manufacturers must be vigilant in the design of the assays in order to reduce the risk of missing a broad range of described S gene mutants.


Asunto(s)
Antígenos de Superficie de la Hepatitis B/análisis , Inmunoensayo , Proteínas Mutantes/análisis , Antígenos de Superficie de la Hepatitis B/genética , Humanos , Proteínas Mutantes/genética , Juego de Reactivos para Diagnóstico , Sensibilidad y Especificidad
16.
J Antimicrob Chemother ; 57(1): 142-5, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16284103

RESUMEN

OBJECTIVES: We studied eight imipenem-resistant isolates of Klebsiella pneumoniae involved in an outbreak in a French teaching hospital. METHODS: The eight isolates were recovered from clinical specimens or rectal swabs. Antibiotic susceptibilities were determined using standard agar diffusion and dilution methods including synergy tests. PFGE was used to study the relatedness of isolates. Genes encoding beta-lactamases were characterized by transfer assays, specific amplification and cloning. RESULTS: The eight isolates were closely related by PFGE analysis and highly related to a K. pneumoniae strain from Greece. They were highly resistant to beta-lactams, including aztreonam and imipenem (MIC > or =32 mg/L), and were positive by the imipenem-EDTA disc synergy test. Isolates were also resistant to aminoglycosides, newer quinolones and sulfamethoxazole, and showed an intermediate level of resistance to tetracycline. VIM-1 and SHV-5 beta-lactamases were revealed in all isolates by PCR. The analysis of plasmid contents of Escherichia coli DH10B electroporants expressing the VIM-1 beta-lactamase or the SHV-5 beta-lactamase confirmed that the two enzymes were coded by two different plasmids. The bla(VIM-1) gene was part of a class 1 integron that also included aac6, dhfrI and aadA genes and was similar to those reported from strains isolated in Greece. CONCLUSIONS: This study confirms the potential risk of spread of multiresistant bacteria with international transfer of patients.


Asunto(s)
Antibacterianos/farmacología , Infección Hospitalaria/microbiología , Brotes de Enfermedades , Farmacorresistencia Bacteriana Múltiple/genética , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/enzimología , beta-Lactamasas/genética , Conjugación Genética , Infección Hospitalaria/epidemiología , ADN Bacteriano/genética , Electroforesis en Gel de Campo Pulsado , Escherichia coli/enzimología , Escherichia coli/genética , Francia , Hospitales Universitarios , Humanos , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , Pruebas de Sensibilidad Microbiana
17.
Liver Transpl ; 11(12): 1550-5, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16315311

RESUMEN

We report 5 cases of acute liver failure related to herpes simplex (HSV) infection in 1 immunocompetent and 4 immunosuppressed patients. One patient was too ill for liver transplantation indication. Three patients, among the 4 listed, underwent liver transplantation. Three patients died 11 days to 1 year after transplantation and 2 patients died 2 to 3 days after admission. All presented with fever and none with skin lesions. The diagnosis of HSV-related hepatitis was made antemortem in only 2 patients on the basis of positive blood cultures and/or immunohistochemic findings. In the remaining patients, HSV diagnosis was made retrospectively on further histologic and virologic investigations. Primary HSV infection was certain or likely in all cases, including an HSV2 superinfection of an anti-HSV1-positive patient and two HSV superinfections of hepatitis B virus (HBV)-related chronic liver disease. In these latter patients, HSV diagnosis was totally unsuspected, despite fever. HSV superinfection has significantly contributed to liver dysfunction aggravation and death. In conclusion, the diagnosis of HSV hepatitis is difficult to establish in the absence of specific clinical signs. This may suggest the need for early administration of acyclovir in patients with suspected HSV hepatitis, without waiting for virologic confirmation. Diagnosis methods providing fast results (real-time polymerase chain reaction [PCR]) should be implemented.


Asunto(s)
Herpes Simple/complicaciones , Fallo Hepático Agudo/patología , Aciclovir/uso terapéutico , Adolescente , Adulto , Anticuerpos Antivirales/análisis , Biopsia , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Herpes Simple/tratamiento farmacológico , Herpes Simple/patología , Humanos , Fallo Hepático Agudo/etiología , Fallo Hepático Agudo/cirugía , Trasplante de Hígado , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Simplexvirus/inmunología , Resultado del Tratamiento
18.
Clin Transplant ; 19(5): 591-9, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16146549

RESUMEN

Cryptogenic cirrhosis (CC) is diagnosed in 5-30% of cirrhotic patients overall and 7% of patients who undergo liver transplantation for cirrhosis. In our series of patients transplanted for CC, pre-transplant clinical and histological data and the post-transplant course were reexamined in an attempt to identify the aetiology. Among the 881 patients transplanted in our centre between 1987 and 2000, 28 patients with a median age of 46 yr (range: 18-69) at transplantation were initially classified as having CC. Two patients were excluded because of intense ischaemic lesions caused by chemoembolization prevented histological analysis of the native liver (n = 1) and because of cryptic HBV infection (n = 1). Among the remaining 26 patients, four groups were individualized: (i) patients with chronic inflammatory liver disease with autoimmune features (n = 14, 54%); (ii) patients with features suggestive of non-alcoholic fatty liver disease (n = 3, 11.5%); (iii); patients with incomplete septal cirrhosis (ISC) and vascular liver disease (n = 3), and (iv) patients with unresolved CC (n = 6, 23%). In the autoimmune liver disease group, the median International Autoimmune Hepatitis score was 12.5 (range: 11-19) after reevaluation and review of the post-transplantation course was helpful to confirm the diagnosis with the occurrence of active graft hepatitis in nine patients, with autoantibodies in five patients. The vascular group was characterized by lesions of obliterative portal venopathy and ISC in all native livers. Diagnosis of NAFLD was based on the clinical background of obesity and/or type 2 diabetes and the presence of steatosis or steatohepatitis in native livers and graft biopsies. A definite aetiological diagnosis can be achieved in the majority of patients initially diagnosed with CC. Autoimmune liver disease emerged as the main aetiology (14 of 26 patients, 54%) and frequently recurred on the grafted liver (nine cases). In all cases a precise diagnosis is obviously of practical interest for better management of post-transplant survey and treatment.


Asunto(s)
Cirrosis Hepática/patología , Trasplante de Hígado , Hígado/patología , Adolescente , Adulto , Anciano , Biopsia , Diagnóstico Diferencial , Hígado Graso/complicaciones , Hígado Graso/patología , Hígado Graso/cirugía , Femenino , Estudios de Seguimiento , Hepatitis Autoinmune/complicaciones , Hepatitis Autoinmune/patología , Hepatitis Autoinmune/cirugía , Humanos , Cirrosis Hepática/etiología , Cirrosis Hepática/cirugía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
19.
Gastroenterol Clin Biol ; 29(5): 573-6, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15980754

RESUMEN

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.


Asunto(s)
Afinidad de Anticuerpos , Hepatitis A/diagnóstico , Hepatitis A/inmunología , Inmunoglobulina G/inmunología , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Niño , Diagnóstico Diferencial , Femenino , Humanos , Inmunoglobulina G/análisis , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Pruebas Serológicas
20.
J Med Virol ; 76(2): 271-8, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15834883

RESUMEN

Investigation of hepatitis A virus (HAV) outbreaks often implies nucleotide sequence analysis. As an alternative method for the identification of related strains, single strand conformation polymorphism method (SSCP) was compared to sequence analysis. Twenty-three strains from sporadic and outbreak cases were studied retrospectively. SSCP, sequence identity and phylogenetic analyses were conducted on a 267 bp fragment of the VP1-2A variable region. The results of SSCP pattern comparison and sequence identity were highly correlated (r = 0.92, P < 0.001). If SSCP showed similar patterns, the VP1-2A fragments had a high and significant probability to have a sequence identity over 99.6%. Results were concordant for outbreak strains. The only discordant result concerned a cluster of three sporadic cases evidenced by phylogenetic analysis while SSCP showed similar patterns for only two of these three cases. A prospective SSCP analysis of a recent HAV outbreak confirmed the reliability of this technique. SSCP may thus provide a rapid and cost-effective tool for preliminary investigation of HAV outbreaks, before undertaking exhaustive nucleotide sequence analysis.


Asunto(s)
Brotes de Enfermedades , Virus de la Hepatitis A/clasificación , Virus de la Hepatitis A/genética , Hepatitis A/epidemiología , Hepatitis A/virología , Polimorfismo Conformacional Retorcido-Simple , Adolescente , Adulto , Niño , Preescolar , Cisteína Endopeptidasas/genética , Femenino , Virus de la Hepatitis A/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Filogenia , Estudios Retrospectivos , Análisis de Secuencia de ADN , Proteínas Virales/genética , Proteínas Estructurales Virales/genética
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