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2.
PLoS One ; 17(9): e0275254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36166463

RESUMO

OBJECTIVE: To assess in ART-naïve pregnant women randomized to efavirenz- versus raltegravir-based ART (IMPAACT P1081) whether pretreatment drug resistance (PDR) with minority frequency variants (<20% of individual's viral quasispecies) affects antiretroviral treatment (ART)-suppression at term. DESIGN: A case-control study design compared PDR minority variants in cases with virologic non-suppression (plasma HIV RNA >200 copies/mL) at delivery to randomly selected ART-suppressed controls. METHODS: HIV pol genotypes were derived from pretreatment plasma specimens by Illumina sequencing. Resistance mutations were assessed using the HIV Stanford Database, and the proportion of cases versus controls with PDR to their ART regimens was compared. RESULTS: PDR was observed in 7 participants (11.3%; 95% CI 4.7, 21.9) and did not differ between 21 cases and 41 controls (4.8% vs 14.6%, p = 0.4061). PDR detected only as minority variants was less common (3.2%; 95% CI 0.2, 11.7) and also did not differ between groups (0% vs. 4.9%; p = 0.5447). Cases' median plasma HIV RNA at delivery was 347c/mL, with most (n = 19/22) showing progressive diminution of viral load but not ≤200c/mL. Among cases with viral rebound (n = 3/22), none had PDR detected. Virologic non-suppression at term was associated with higher plasma HIV RNA at study entry (p<0.0001), a shorter duration of ART prior to delivery (p<0.0001), and randomization to efavirenz- (versus raltegravir-) based ART (p = 0.0085). CONCLUSIONS: We observed a moderate frequency of PDR that did not significantly contribute to virologic non-suppression at term. Rather, higher pretreatment plasma HIV RNA, randomization to efavirenz-based ART, and shorter duration of ART were associated with non-suppression. These findings support early prenatal care engagement of pregnant women and initiation of integrase inhibitor-based ART due to its association with more rapid suppression of plasma RNA levels. Furthermore, because minority variants appeared infrequent in ART-naïve pregnant women and inconsequential to ART-suppression, testing for minority variants may be unwarranted.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Inibidores de Integrase de HIV , HIV-1 , Alcinos , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Antirretrovirais/uso terapêutico , Benzoxazinas , Estudos de Casos e Controles , Ciclopropanos , Farmacorresistência Viral/genética , Feminino , Infecções por HIV/tratamento farmacológico , Inibidores de Integrase de HIV/uso terapêutico , HIV-1/genética , Humanos , Preparações Farmacêuticas , Gravidez , Gestantes , RNA , Raltegravir Potássico/uso terapêutico , Carga Viral
3.
Clin Infect Dis ; 74(11): 2001-2009, 2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34467974

RESUMO

BACKGROUND: We aimed to assess if maternal human immunodeficiency virus (HIV) drug resistance is associated with an increased risk of HIV vertical transmission and to describe the dynamics of drug resistance in HIV-infected infants. METHODS: This was a case-control study of PROMISE study participants. "Cases" were mother-infant pairs with HIV vertical transmission during pregnancy or breastfeeding and "controls" were mother-infant pairs without transmission matched 1:3 by delivery date and clinical site. Genotypic HIV drug resistance analyses were performed on mothers' and their infants' plasma at or near the time of infant HIV diagnosis. Longitudinal analysis of genotypic resistance was assessed in available specimens from infants, from diagnosis and beyond, including antiretroviral therapy (ART) initiation and last study visits. RESULTS: Our analyses included 85 cases and 255 matched controls. Maternal HIV drug resistance, adjusted for plasma HIV RNA load at infant HIV diagnosis, enrollment CD4 count, and antepartum regimens, was not associated with in utero/peripartum HIV transmission. In contrast, both maternal plasma HIV RNA load and HIV drug resistance were independent risk factors associated with vertical transmission during breastfeeding. Furthermore, HIV drug resistance was selected across infected infants during infancy. CONCLUSIONS: Maternal HIV drug resistance and maternal viral load were independent risk factors for vertical transmission during breastfeeding, suggesting that nevirapine alone may be insufficient infant prophylaxis against drug-resistant variants in maternal breast milk. These findings support efforts to achieve suppression of HIV replication during pregnancy and suggest that breastfeeding infants may benefit from prophylaxis with a greater barrier to drug resistance than nevirapine alone.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Complicações Infecciosas na Gravidez , Fármacos Anti-HIV/uso terapêutico , Aleitamento Materno , Estudos de Casos e Controles , Resistência a Medicamentos , Feminino , HIV , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Nevirapina/uso terapêutico , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , RNA/uso terapêutico
4.
AIDS Res Hum Retroviruses ; 37(7): 534-541, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33794657

RESUMO

Hepatitis E virus (HEV) is thought to be common in the United States with increased prevalence in those with concomitant hepatitis C virus (HCV) or HCV/HIV coinfection. Little is known regarding true prevalence, incidence, and antibody seroreversion in these populations. We sought to define these rates among HCV and HCV/HIV coinfected persons in the Washington, DC area. Two longitudinal cohorts of HCV and HCV/HIV coinfected subjects from the Washington, DC area were evaluated. Multiple HEV test modalities were deployed including immunoglobulin G (IgG) and immunoglobulin M (IgM) antibody testing, evaluation of antibody avidity, HEV RNA testing, and HEV enzyme-linked immune absorbent spot (ELISPOT) analysis. A total of 379 individuals were evaluated including 196 who were HCV monoinfected and 183 HCV/HIV coinfected. Anti-HEV IgG was detected and confirmed in 18.7% of the cohort at baseline. None demonstrated anti-HEV IgM positive or HEV RNA positive results. Proportions of HEV antibody prevalence did not significantly differ between groups. Longitudinal follow-up samples were available for 226 individuals with a mean follow-up time of 24 months. Seroreversion was noted in 1.8%. One HCV/HIV infected person seroconverted to HEV IgG positivity in the followed cohort. About 40% of the positive population demonstrated high avidity suggestive of more remote exposure. Interferon gamma ELISPOT was performed in 70 subjects and false negative and false positive HEV enzyme-linked immunosorbent assay antibodies were identified. In HIV-infected persons in the United States HEV exposure and seroconversion is frequent enough that HEV should be considered in the differential diagnosis of acute hepatitis. Seroreversion may lead to underestimation of true infection risk.


Assuntos
Coinfecção , Infecções por HIV , Hepatite C , Hepatite E , Coinfecção/epidemiologia , Infecções por HIV/complicações , Hepacivirus , Hepatite C/complicações , Hepatite C/epidemiologia , Hepatite E/complicações , Hepatite E/epidemiologia , Humanos , RNA Viral
5.
Virus Genes ; 55(5): 707-712, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31346975

RESUMO

Hepatitis B virus (HBV) exhibits a high degree of heterogeneity with at least 10 genotypes (A-J) identified to date. Intergenotypic recombination is relatively common. Previously, we investigated HBV drug resistance in HIV/HBV co-infected individuals in Ghana. After identifying multiple circulating genotypes and a novel D/E recombinant, we sought to determine if additional individuals were also infected with recombinant HBV. Partial genome sequences from three individuals were initially identified as genotype A4. Full-length HBV genomes were obtained using rolling circle amplification followed by PCR and shown to cluster with known A/E recombinant viruses. Similar recombination breakpoints were observed in these three individuals suggesting local spread of this novel recombinant HBV in Ghana.


Assuntos
Genótipo , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Hepatite B/virologia , Recombinação Genética , Adulto , Análise por Conglomerados , Feminino , Gana , Vírus da Hepatite B/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Sequenciamento Completo do Genoma
6.
Dig Dis Sci ; 63(3): 645-652, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29330726

RESUMO

BACKGROUND AND AIMS: The prevalence of naturally occurring HCV-NS5A resistance-associated substitutions (RAS) to DAA drugs might affect the response to treatment in HCV/HIV coinfected subjects. There are limited data on the frequency of HCV-NS5A naturally occurring drug-RAS at baseline in HCV/HIV coinfected patients when ultra-deep sequencing methodologies are applied. METHODS: HCV-NS5A-RAS were evaluated among 25 subjects in each group. Patients were matched by age, gender, and hepatic fibrosis stage category to control for selection bias. RESULTS: Within subtype 1a, RAS were observed in 28% of HCV monoinfected and 48% of HCV/HIV coinfected subjects. More patients in the HCV/HIV coinfected group had clinically relevant mutations to DAA directed at NS5A. CONCLUSION: While the clinical significance of this observation may be limited in highly drug adherent populations, some HCV/HIV coinfected persons may be at greater risk of viral resistance if suboptimal dosing occurs.


Assuntos
Coinfecção/virologia , Farmacorresistência Viral/genética , Infecções por HIV/virologia , Hepacivirus/genética , Hepatite C/virologia , Proteínas não Estruturais Virais/genética , Adulto , Antivirais , Benzofuranos , Estudos de Casos e Controles , Combinação de Medicamentos , Feminino , Hepatite C/tratamento farmacológico , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imidazóis , Masculino , Pessoa de Meia-Idade , Quinoxalinas
7.
Virus Genes ; 53(4): 538-547, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28567562

RESUMO

Globally, there are approximately 240 million people chronically infected with hepatitis B virus (HBV)-a major cause of hepatocellular carcinoma. Ten different HBV genotypes (A-J) have been identified with distinct geographic distributions. Novel variants generated by recombination between different HBV genotypes have been documented worldwide and represent an important element of genetic variability with possible clinical implications. Here, the complete genome sequence of an HBV genotype D/E recombinant from Ghana is reported. The full-length sequence was obtained using rolling circle amplification followed by PCR and sequenced using next-generation sequencing (NGS). A consensus sequence was extracted from the NGS data and underwent phylogenetic analysis to determine genotype, as well as the recombination pattern. Subsequently, the sequence was compared to recombinants described previously in Africa. Based on MCMC phylogenetic analysis, SimPlot recombination analyses, and intragroup genetic distance, the isolate 007N full-length genome is unique compared to other reported D/E recombinants in Africa.


Assuntos
Vírus da Hepatite B/genética , Hepatite B/virologia , Recombinação Genética , África , Genoma Viral , Genótipo , Vírus da Hepatite B/classificação , Vírus da Hepatite B/isolamento & purificação , Humanos , Filogenia
8.
Antivir Ther ; 22(1): 13-20, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27167598

RESUMO

BACKGROUND: The presence of HBV resistance mutations upon initiation or during antiretroviral therapy (ART) in HIV-coinfected patients is an important determinant of treatment response. The main objective of the study was to determine the prevalence of HBV resistance mutations in antiretroviral treatment-naive and treatment-experienced HBV-HIV-coinfected Ghanaian patients with detectable HBV viraemia. METHODS: HBV-HIV-coinfected patients who were ART-naive or had received at least 9 months of lamivudine (3TC)-containing ART were enrolled in a cross-sectional study. Demographic and clinical data were collected and HBV DNA quantified. Partial HBV sequences were amplified by PCR and sequenced bi-directionally to obtain a 2.1-2.2 kb fragment for phylogenetic analysis of HBV genotypes and evaluation of drug resistance mutations. RESULTS: Of the 100 HBV-HIV-coinfected study patients, 75 were successfully PCR-amplified, and 63 were successfully sequenced. Of these 63 patients, 27 (42.9%) were ART-experienced and 58 (92.1%) had HBV genotype E. No resistance mutations were observed in the 36 ART-naive patients, while 21 (77.8%) of 27 treatment-experienced patients had resistance mutations. All patients with resistance mutations had no tenofovir in their regimens, and 80% of them had HIV RNA <40 copies/ml. The 3TC resistance mutations rtL180M and rtM204V were observed in 10 (47.6%) of the 21 patients, while 5 patients (23.8%) had rtV173L, rtL180M and rtM204V mutations. CONCLUSIONS: A high proportion of HBV-HIV-coinfected patients with detectable viraemia on 3TC-containing ART had resistance mutations despite good ART adherence as determined by HIV RNA suppression. This study emphasizes the need for dual therapy as part of a fully suppressive ART in all HBV-HIV-coinfected patients in Ghana.


Assuntos
Coinfecção/tratamento farmacológico , Coinfecção/virologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Vírus da Hepatite B/genética , Hepatite B/tratamento farmacológico , Hepatite B/virologia , Fármacos Anti-HIV/uso terapêutico , Antivirais/uso terapêutico , Estudos Transversais , DNA Viral/sangue , DNA Viral/genética , Farmacorresistência Viral/genética , Genótipo , Gana , Infecções por HIV/complicações , Hepatite B/complicações , Vírus da Hepatite B/efeitos dos fármacos , Humanos , Lamivudina/uso terapêutico , Mutação , Carga Viral
9.
J Gen Virol ; 97(7): 1615-1624, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27031988

RESUMO

Occult hepatitis B is defined by the presence of hepatitis B virus (HBV) DNA in the absence of hepatitis B surface antigen (HBsAg). Occult HBV is associated with the development of hepatocellular carcinoma, reactivation during immune suppression, and virus transmission. Viral mutations contribute significantly to the occult HBV phenotype. Mutations in the 'a' determinant of HBsAg are of particular interest, as these mutations are associated with immune escape, vaccine escape and diagnostic failure. We examined the effects of selected occult HBV-associated mutations identified in a population of HIV-positive South Africans on HBsAg production in vitro. Mutations were inserted into two different chronic HBV backbones and transfected into a hepatocyte-derived cell line. HBsAg levels were quantified by enzyme-linked immunosorbent assay (ELISA), while the detectability of mutant HBsAg was determined using an HA-tagged HBsAg expression system. Of the seven mutations analysed, four (S132P, C138Y, N146D and C147Y) resulted in decreased HBsAg expression in one viral background but not in the second viral background. One mutation (N146D) led to a decrease in HBsAg detected as compared to HA-tag, indicating that this mutation compromises the ability of the ELISA to detect HBsAg. The contribution of occult-associated mutations to the HBsAg-negative phenotype of occult HBV cannot be determined adequately by testing the effect of the mutation in a single viral background, and rigorous analysis of these mutations is required.


Assuntos
DNA Viral/genética , Antígenos de Superfície da Hepatite B/sangue , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B Crônica/diagnóstico , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Soropositividade para HIV/complicações , Hepatite B Crônica/virologia , Humanos , Neoplasias Hepáticas/virologia , Mutagênese Sítio-Dirigida , Mutação/genética , África do Sul
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