Duration of viremia and fecal shedding of the virus in hepatitis A infected children

La infección por el virus de hepatitis A (HAV) es endémica en Argentina. El uso de técnicas moleculares permitió extender la detección del RNA del HAV en suero y heces en pacientes con diferentes presentaciones clínicas. Comparamos la sensibilidad del protocolo de RT-PCR que usamos con cebadores dirigidos a distintas regiones del genoma, resultando la detección de la región VP3 C terminal la más sensible. Se obtuvieron prospectivamente muestras de suero y materia fecal de 20 niños con hepatitis aguda autolimitada por HAV. El RNA del HAV fue detectado en 18/20 niños en muestras basales y en 19/20 sumando una muestra posterior. El RNA del HAV fue detectable en 9/20 pacientes hasta 30 días en suero; en materia fecal en 2/20 hasta 60 días y en 1/20 hasta 90 días. La secuencia genómica para la región VP1/2A en 8 muestras demostró que todas pertenecían al subgenotipo IA, aunque eran diferentes entre sí. Solo en 1/11 niños con falla hepática fulminante fue posible la detección del RNA del HAV utilizando la región VP3 C terminal y el genotipo fue I. La reciente introducción de la vacunación universal en niños de 1 año de edad en Argentina podría disminuir drásticamente la circulación del virus emergiendo nuevas fuentes de infección y permitiendo la introducción de nuevos genotipos. Las técnicas moleculares aplicadas al estudio de la historia natural de la infección y a la vigilancia epidemiológica contribuyen al control y la toma de decisiones eficientes en políticas de Salud Pública.Hepatitis A virus (HAV) infection is endemic in Argentina. Molecular tools have allowed HAV RNA detection to be extent to sera and feces from patients with different clinical backgrounds. We compare the sensitivity of the RT-PCR protocol we follow using primers targeting different genomic regions and VP3 C terminal was the most sensitive. Sequential sera and fecal samples were obtained from 20 children with acute self limited Hepatitis A. HAV RNA was detectable in 18/20 children if sera and stool specimens were collected at the onset of symptoms and in 19/20 if a later sample was considered. HAV RNA was detectable in serum from 9/20 patients until day 30 and in feces from 2 patients until day 60 and until day 90 in one. Genomic sequences from VP1/2A region in 8 samples showed they all belong to subgenotype IA although they were different between them. HAV RNA was detectable only in 1/11 sera from children with acute liver failure when VP3 C terminal fragment was searched and it belonged to genotype I. Universal vaccination in one year old children was recently implemented in Argentina and it will dramatically enable the decrease of the viral circulation, making new sources of infection emerge and allowing the introduction of new genotypes. The application of molecular tools to the study of the natural history of infection and to the epidemiologic surveillance may contribute to efficient control and lead to rational decisions in public health policies.Fil: Munné, María Silvina. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Cañero Velasco, María C. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Moreiro, Rita. Hospital Nacional de Pediatría J. P. Garrahan. Laboratorio; Argentina.Fil: Vladimirsky, Sara. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Otegui, Lucio. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Castro, Raúl. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Brajterman, Leonardo. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Soto, Sonia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Mutti, Jorge. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Nucifora, Silvia. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Lara, Elena. Hospital Municipal del Niño de San Justo. Laboratorio Central; Argentina.Fil: Sosa, Anibal. Hospital Municipal del Niño de San Justo. Laboratorio Central; Argentina.Fil: Godoy, Patricia. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Ciocca, Mirta. Hospital Nacional de Pediatría J. P. Garrahan. Unidad de Hígado; Argentina.Fil: Cuarterolo, Miriam. Hospital Nacional de Pediatría J. P. Garrahan. Unidad de Hígado; Argentina.Fil: Quarleri, Jorge F. Facultad de Medicina. Centro Nacional de Referencia para el SIDA; Argentina.Fil: González, Jorge E. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina

Duration of viremia and fecal shedding of the virus in hepatitis A infected children

La infección por el virus de hepatitis A (HAV) es endémica en Argentina. El uso de técnicas moleculares permitió extender la detección del RNA del HAV en suero y heces en pacientes con diferentes presentaciones clínicas. Comparamos la sensibilidad del protocolo de RT-PCR que usamos con cebadores dirigidos a distintas regiones del genoma, resultando la detección de la región VP3 C terminal la más sensible. Se obtuvieron prospectivamente muestras de suero y materia fecal de 20 niños con hepatitis aguda autolimitada por HAV. El RNA del HAV fue detectado en 18/20 niños en muestras basales y en 19/20 sumando una muestra posterior. El RNA del HAV fue detectable en 9/20 pacientes hasta 30 días en suero; en materia fecal en 2/20 hasta 60 días y en 1/20 hasta 90 días. La secuencia genómica para la región VP1/2A en 8 muestras demostró que todas pertenecían al subgenotipo IA, aunque eran diferentes entre sí. Solo en 1/11 niños con falla hepática fulminante fue posible la detección del RNA del HAV utilizando la región VP3 C terminal y el genotipo fue I. La reciente introducción de la vacunación universal en niños de 1 año de edad en Argentina podría disminuir drásticamente la circulación del virus emergiendo nuevas fuentes de infección y permitiendo la introducción de nuevos genotipos. Las técnicas moleculares aplicadas al estudio de la historia natural de la infección y a la vigilancia epidemiológica contribuyen al control y la toma de decisiones eficientes en políticas de Salud Pública.Hepatitis A virus (HAV) infection is endemic in Argentina. Molecular tools have allowed HAV RNA detection to be extent to sera and feces from patients with different clinical backgrounds. We compare the sensitivity of the RT-PCR protocol we follow using primers targeting different genomic regions and VP3 C terminal was the most sensitive. Sequential sera and fecal samples were obtained from 20 children with acute self limited Hepatitis A. HAV RNA was detectable in 18/20 children if sera and stool specimens were collected at the onset of symptoms and in 19/20 if a later sample was considered. HAV RNA was detectable in serum from 9/20 patients until day 30 and in feces from 2 patients until day 60 and until day 90 in one. Genomic sequences from VP1/2A region in 8 samples showed they all belong to subgenotype IA although they were different between them. HAV RNA was detectable only in 1/11 sera from children with acute liver failure when VP3 C terminal fragment was searched and it belonged to genotype I. Universal vaccination in one year old children was recently implemented in Argentina and it will dramatically enable the decrease of the viral circulation, making new sources of infection emerge and allowing the introduction of new genotypes. The application of molecular tools to the study of the natural history of infection and to the epidemiologic surveillance may contribute to efficient control and lead to rational decisions in public health policies.Fil: Munné, María Silvina. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Cañero Velasco, María C. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Moreiro, Rita. Hospital Nacional de Pediatría J. P. Garrahan. Laboratorio; Argentina.Fil: Vladimirsky, Sara. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Otegui, Lucio. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Castro, Raúl. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Brajterman, Leonardo. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Soto, Sonia. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina.Fil: Mutti, Jorge. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Nucifora, Silvia. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Lara, Elena. Hospital Municipal del Niño de San Justo. Laboratorio Central; Argentina.Fil: Sosa, Anibal. Hospital Municipal del Niño de San Justo. Laboratorio Central; Argentina.Fil: Godoy, Patricia. Hospital Municipal del Niño de San Justo. Unidad de Gastroenterología y Hepatología; Argentina.Fil: Ciocca, Mirta. Hospital Nacional de Pediatría J. P. Garrahan. Unidad de Hígado; Argentina.Fil: Cuarterolo, Miriam. Hospital Nacional de Pediatría J. P. Garrahan. Unidad de Hígado; Argentina.Fil: Quarleri, Jorge F. Facultad de Medicina. Centro Nacional de Referencia para el SIDA; Argentina.Fil: González, Jorge E. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas. Laboratorio Nacional de Referencia de Hepatitis Virales; Argentina

Unsuccessful therapy with adefovir and entecavir-tenofovir in a patient with chronic hepatitis B infection with previous resistance to lamivudine: a fourteen-year evolution of hepatitis B virus mutations

<p>Abstract</p> <p>Background</p> <p>Complex mutants can be selected under sequential selective pressure by HBV therapy. To determine hepatitis B virus genomic evolution during antiviral therapy we characterized the HBV quasi-species in a patient who did no respond to therapy following lamivudine breakthrough for a period of 14 years.</p> <p>Case Presentation</p> <p>The polymerase and precore/core genes were amplified and sequenced at determined intervals in a period of 14 years. HBV viral load and HBeAg/Anti-HBe serological profiles as well as amino transferase levels were also measured. A mixture of lamivudine-resistant genotype A2 HBV strains harboring the rtM204V mutation coexisted in the patient following viral breakthrough to lamivudine. The L180M+M204V dominant mutant displayed strong lamivudine-resistance. As therapy was changed to adefovir, then to entecavir, and finally to entecavir-tenofovir the viral load showed fluctuations but lamivudine-resistant strains continued to be selected, with minor contributions to the HBV quasi-species composition of additional resistance-associated mutations. At the end of the 14-year follow up period, high viral loads were predominant, with viral strains harboring the lamivudine-resistance signature rtL180M+M204V. The precore/core frame A1762T and G1764A double mutation was detected before treatment and remaining in this condition during the entire follow-up. Specific entecavir and tenofovir primary resistance-associated mutations were not detected at any time. Plasma concentrations of tenofovir indicated adequate metabolism of the drug.</p> <p>Conclusions</p> <p>We report the selection of HBV mutants carrying well-defined primary resistance mutations that escaped lamivudine in a fourteen-year follow-up period. With the exception of tenofovir resistance mutations, subsequent unselected primary resistance mutations were detected as minor populations into the HBV quasispecies composition during adefovir or entecavir monotherapies. Although tenofovir is considered an appropriate therapeutic alternative for the treatment of entecavir-unresponsive patients, its use was not effective in the case reported here.</p

HIV-1 tropism dynamics and phylogenetic analysis from longitudinal ultra-deep sequencing data of CCR5- and CXCR4-using variants.

Coreceptor switch from CCR5 to CXCR4 is associated with HIV disease progression. The molecular and evolutionary mechanisms underlying the CCR5 to CXCR4 switch are the focus of intense recent research. We studied the HIV-1 tropism dynamics in relation to coreceptor usage, the nature of quasispecies from ultra deep sequencing (UDPS) data and their phylogenetic relationships.Here, we characterized C2-V3-C3 sequences of HIV obtained from 19 patients followed up for 54 to 114 months using UDPS, with further genotyping and phylogenetic analysis for coreceptor usage. HIV quasispecies diversity and variability as well as HIV plasma viral load were measured longitudinally and their relationship with the HIV coreceptor usage was analyzed. The longitudinal UDPS data were submitted to phylogenetic analysis and sampling times and coreceptor usage were mapped onto the trees obtained.Although a temporal viral genetic structuring was evident, the persistence of several viral lineages evolving independently along the infection was statistically supported, indicating a complex scenario for the evolution of viral quasispecies. HIV X4-using variants were present in most of our patients, exhibiting a dissimilar inter- and intra-patient predominance as the component of quasispecies even on antiretroviral therapy. The viral populations from some of the patients studied displayed evidences of the evolution of X4 variants through fitness valleys, whereas for other patients the data favored a gradual mode of emergence.CXCR4 usage can emerge independently, in multiple lineages, along the course of HIV infection. The mode of emergence, i.e. gradual or through fitness valleys seems to depend on both virus and patient factors. Furthermore, our analyses suggest that, besides becoming dominant after population-level switches, minor proportions of X4 viruses might exist along the infection, perhaps even at early stages of it. The fate of these minor variants might depend on both viral and host factors

Astrocyte Apoptosis and HIV Replication Are Modulated in Host Cells Coinfected with Trypanosoma cruzi

The protozoan Trypanosoma cruzi is the etiological agent of Chagas disease. In immunosuppressed individuals, as it occurs in the coinfection with human immunodeficiency virus (HIV), the central nervous system may be affected. In this regard, reactivation of Chagas disease is severe and often lethal, and it accounts for meningoencephalitis. Astrocytes play a crucial role in the environment maintenance of healthy neurons; however, they can host HIV and T. cruzi. In this report, human astrocytes were infected in vitro with both genetically modified-pathogens to express alternative fluorophore. As evidenced by fluorescence microscopy and flow cytometry, HIV and T. cruzi coexist in the same astrocyte, likely favoring reciprocal interactions. In this context, lower rates of cell death were observed in both T. cruzi monoinfected-astrocytes and HIV-T. cruzi coinfection in comparison with those infected only with HIV. The level of HIV replication is significantly diminished under T. cruzi coinfection, but without affecting the infectivity of the HIV progeny. This interference with viral replication appears to be related to the T. cruzi multiplication rate or its increased intracellular presence but does not require their intracellular cohabitation or infected cell-to-cell contact. Among several Th1/Th2/Th17 profile-related cytokines, only IL-6 was overexpressed in HIV-T. cruzi coinfection exhibiting its cytoprotective role. This study demonstrates that T. cruzi and HIV are able to coinfect astrocytes thus altering viral replication and apoptosis

In Vitro Detection of Dissimilar Amounts of Hepatitis C Virus (HCV) Subtype-Specific RNA Genomes in Mixes Prepared from Sera of Persons Infected with a Single HCV Genotype

The level of in vitro detection of viral genomes in mixes with two different hepatitis C virus (HCV) subtypes was investigated by artificially mixing previously measured subtype-specific HCV RNA genomes. The RNAs in these mixtures were reverse transcribed and then PCR amplified by using two sets of primers corresponding to the 5′ untranslated region and digested with endonucleases to analyze the restriction fragment length polymorphism patterns. This approach facilitated detection of a wider range of type-specific HCV genomes than originally described, beyond equimolar concentrations of contributing HCV subtypes. Moreover, by using computerized image analysis, this study also demonstrated that the true contribution of each virus type—and consequently of mixed infections—may be underestimated when only visual observation is carried out. These results may be useful for comparing data obtained from this and other currently used methodologies

Maximum likelihood phylogenetic tree of C2-V3-C3 nucleotide sequences from patients included in the study.

<p>Patient-related clusters are identified in different colors as indicated at the bottom of the figure. The vertical size of the clusters is proportional to the number of reads in the cluster and the horizontal size of the clusters shows their maximum genetic depth. Bootstrap values are given on branches. Branch lengths are proportional to the number of nucleotide substitutions per aligned site (bar = 0.1 substitutions).</p

Intra-patient relative abundance of R5 and X4-using variants identified over time.

<p>Longitudinal analysis of the relative abundance (y left axis: percentage) of R5 (blue range) and X4 (red range) variants at different time points (x axis: sampling times in months). At the first sampling time, the most abundant variant is identified by darker color and named as “R5.1” or “X4.1”, accordingly. Colors become clearer according to the decrease in their relative abundance. “R5.ot” and “X4.ot” include those viral variants with very low relative abundance. For subsequent sampling times, the color palette is respected following the first one in order to allow correlating the longitudinal variation of the viral variants first identified. HIV viral load are represented (y right axis; as log copies/ml). The V3 amino acid sequence (and between brackets, their relative false positive rate by geno2pheno) of the most common variants in each patient is shown.</p

Bootstrap (<i>B</i>) and Shimodaira-Hasegawa (<i>SH</i>) supports observed inside single-patient datasets¹.

1<p>Mean (<i>MN</i>), median (<i>MD</i>), standard deviation (<i>SD</i>).</p