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1.
J Infect Dis ; 226(5): 812-821, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-35230450

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleocapsid antigen (N-Ag) can be detected in the blood of patients with coronavirus disease 2019 (COVID-19). We used a highly sensitive and specific assay to explore the presence of N-Ag in urine during the course of COVID-19 and its relationship with the severity of disease. METHODS: We studied urinary and plasma N-Ag using a highly sensitive immunoassay in 82 patients with SARS-CoV-2 infection proved by polymerase chain reaction. RESULTS: In the first and second weeks of COVID-19, hospitalized patients tested positive for urinary N-Ag (81.25% and 71.79%, respectively) and plasma N-Ag (93.75% and 94.87%, respectively). High urinary N-Ag levels were associated with the absence of SARS-CoV-2 nucleocapsid antibodies, admission in intensive care units, high C-reactive protein levels, lymphopenia, eosinopenia, and high lactate dehydrogenase levels. Higher accuracy was observed for urinary N-Ag as a predictor of severe COVID-19 than for plasma N-Ag. CONCLUSIONS: Our study demonstrates that N-Ag is present in the urine of patients hospitalized in the early phase of COVID-19. As a direct marker of SARS-CoV-2, urinary N-Ag reflects the dissemination of viral compounds in the body. Urinary N-Ag may be a useful marker for disease severity in SARS-CoV-2 infections.


Assuntos
COVID-19 , Anticorpos Antivirais , Antígenos Virais , Proteínas do Nucleocapsídeo de Coronavírus , Humanos , Nucleocapsídeo/análise , SARS-CoV-2 , Sensibilidade e Especificidade
2.
Euro Surveill ; 27(25)2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35748300

RESUMO

BackgroundWest Nile virus (WNV) and Usutu virus (USUV), two closely related flaviviruses, mainly follow an enzootic cycle involving mosquitoes and birds, but also infect humans and other mammals. Since 2010, their epidemiological situation may have shifted from irregular epidemics to endemicity in several European regions; this requires confirmation, as it could have implications for risk assessment and surveillance strategies.AimTo explore the seroprevalence in animals and humans and potential endemicity of WNV and USUV in Southern France, given a long history of WNV outbreaks and the only severe human USUV case in France in this region.MethodsWe evaluated the prevalence of WNV and USUV in a repeated cross-sectional study by serological and molecular analyses of human, dog, horse, bird and mosquito samples in the Camargue area, including the city of Montpellier, between 2016 and 2020.ResultsWe observed the active transmission of both viruses and higher USUV prevalence in humans, dogs, birds and mosquitoes, while WNV prevalence was higher in horses. In 500 human samples, 15 were positive for USUV and 6 for WNV. Genetic data showed that the same lineages, WNV lineage 1a and USUV lineage Africa 3, were found in mosquitoes in 2015, 2018 and 2020.ConclusionThese findings support existing literature suggesting endemisation in the study region and contribute to a better understanding of USUV and WNV circulation in Southern France. Our study underlines the importance of a One Health approach for the surveillance of these viruses.


Assuntos
Culicidae , Infecções por Flavivirus , Saúde Única , Febre do Nilo Ocidental , Animais , Aves/virologia , Estudos Transversais , Culicidae/virologia , Cães/virologia , Flavivirus/genética , Infecções por Flavivirus/epidemiologia , Infecções por Flavivirus/veterinária , França/epidemiologia , Cavalos/virologia , Humanos , Estudos Soroepidemiológicos , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/genética
3.
J Infect Dis ; 223(4): 562-567, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33206973

RESUMO

We assessed the expression of CD169, a type I interferon-inducible receptor, on monocytes (monocyte CD169 [mCD169]) in 53 adult patients admitted to the hospital during the coronavirus disease 2019 (COVID-19) outbreak for a suspicion of severe acute respiratory syndrome coronavirus 2 infection. Monocyte CD169 was strongly overexpressed in 30 of 32 (93.7%) confirmed COVID-19 cases, compared with 3 of 21 (14.3%) patients in whom the diagnosis of COVID-19 was finally ruled out. Monocyte CD169 was associated with the plasma interferon-alpha level and thrombocytopenia. Monocyte CD169 testing may be helpful for the rapid triage of suspected COVID-19 patients during an outbreak.


Assuntos
COVID-19/diagnóstico , Monócitos/metabolismo , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Idoso , Biomarcadores/metabolismo , COVID-19/metabolismo , Diagnóstico Precoce , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/virologia , Curva ROC
4.
Clin Infect Dis ; 72(6): 1026-1032, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32067040

RESUMO

BACKGROUND: Immune control of Epstein-Barr virus (EBV) infection is impaired in individuals with HIV. We explored maternal factors associated with EBV acquisition in HIV-exposed uninfected (HEU) infants and the relationship between EBV infection and serious adverse events (SAEs) during the first year of life. METHODS: 201 HEU infants from Uganda enrolled in the ANRS 12174 trial were tested for antiviral capsid antigen (anti-VCA) antibodies at week 50. Date of infection was estimated by testing EBV DNA at weeks 1, 6, 14, 26, 38, and 50 postpartum on dried blood spots. RESULTS: Eighty-seven (43%) infants tested positive for anti-VCA IgG at week 50. Among the 59 infants positive for EBV DNA, 25% were infected within the first 26 weeks. Almost half (12%) were infected before week 14. Shedding of EBV in breast milk was associated with EBV DNA in maternal plasma (P = .009), HIV RNA detection (P = .039), and lower CD4 count (P = .001) and correlated with plasma EBV DNA levels (P = .002). EBV infant infection at week 50 was associated with shedding of EBV in breast milk (P = .009) and young maternal age (P = .029). Occurrence of a clinical SAE, including malaria and pneumonia, was associated with higher levels of EBV DNA in infants (P = .010). CONCLUSIONS: By assessing EBV infection in HEU infants we observed that infection during the first year is determined by HIV and EBV maternal factors and that EBV DNA levels were higher among infants with clinical SAEs. CLINICAL TRIALS REGISTRATION: NCT00640263.


Assuntos
Infecções por Vírus Epstein-Barr , Infecções por HIV , Anticorpos Antivirais , Fatores Biológicos , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/epidemiologia , Feminino , HIV , Infecções por HIV/complicações , Herpesvirus Humano 4 , Humanos , Lactente , Uganda/epidemiologia
5.
Clin Infect Dis ; 72(10): 1701-1708, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32516409

RESUMO

BACKGROUND: Human encephalitis represents a medical challenge from a diagnostic and therapeutic point of view. We investigated the cause of 2 fatal cases of encephalitis of unknown origin in immunocompromised patients. METHODS: Untargeted metatranscriptomics was applied on the brain tissue of 2 patients to search for pathogens (viruses, bacteria, fungi, or protozoans) without a prior hypothesis. RESULTS: Umbre arbovirus, an orthobunyavirus never previously identified in humans, was found in 2 patients. In situ hybridization and reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) showed that Umbre virus infected neurons and replicated at high titers. The virus was not detected in cerebrospinal fluid by RT-qPCR. Viral sequences related to Koongol virus, another orthobunyavirus close to Umbre virus, were found in Culex pipiens mosquitoes captured in the south of France where the patients had spent some time before the onset of symptoms, demonstrating the presence of the same clade of arboviruses in Europe and their potential public health impact. A serological survey conducted in the same area did not identify individuals positive for Umbre virus. The absence of seropositivity in the population may not reflect the actual risk of disease transmission in immunocompromised individuals. CONCLUSIONS: Umbre arbovirus can cause encephalitis in immunocompromised humans and is present in Europe.


Assuntos
Agamaglobulinemia , Encefalite , Orthobunyavirus , Vírus , Animais , Europa (Continente) , França/epidemiologia , Humanos , Orthobunyavirus/genética
6.
J Med Virol ; 93(5): 3069-3076, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33554363

RESUMO

The implementation of rapid diagnostic tests (RDTs) may enhance the efficiency of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing, as RDTs are widely accessible and easy to use. The aim of this study was to evaluate the performance of a diagnosis strategy based on a combination of antigen and immunoglobulin M (IgM) or immunoglobulin G (IgG) serological RDTs. Plasma and nasopharyngeal samples were collected between 14 March and 11 April 2020 at hospital admission from 45 patients with reverse transcription polymerase chain reaction (RT-PCR) confirmed COVID-19 and 20 negative controls. SARS-CoV-2 antigen (Ag) was assessed in nasopharyngeal swabs using the Coris Respi-Strip. For IgM/IgG detection, SureScreen Diagnostics and Szybio Biotech RDTs were used in addition to laboratory assays (Abbott Alinity i SARS-CoV-2 IgG and Theradiag COVID-19 IgM enzyme-linked immunosorbent assay). Using the Ag RDT, 13 out of 45 (29.0%) specimens tested positive, the sensitivity was 87.0% for cycle threshold (Ct ) values ≤25% and 0% for Ct values greater than 25. IgG detection was associated with high Ct values and the amount of time after the onset of symptoms. The profile of isolated IgM on RDTs was more frequently observed during the first and second week after the onset of symptoms. The combination of Ag and IgM/IgG RDTs enabled the detection of up to 84.0% of COVID-19 confirmed cases at hospital admission. Antigen and antibody-based RDTs showed suboptimal performances when used alone. However when used in combination, they are able to identify most COVID-19 patients admitted in an emergency department.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/virologia , Ensaio de Imunoadsorção Enzimática , Feminino , Hospitalização , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Testes Sorológicos/métodos
7.
J Viral Hepat ; 27(5): 540-543, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31895489

RESUMO

Diagnostic of acute hepatitis A virus (HAV) infection is based on the detection of anti-HAV IgM without testing for the pathogen itself. We evaluated the usefulness of HAV RNA testing for confirmation of acute hepatitis A and to provide indications about the level of HAV replication in HIV-positive and HIV-negative subjects during an unprecedented outbreak of HAV observed in France in 2017. HAV RNA was detected in 38 out of 41 (92.6%) subjects with a clinical diagnosis of acute hepatitis A, whereas nine cases tested positive for anti-HAV IgM in whom the diagnosis of acute hepatitis A was not retained were found negative for HAV RNA. All subjects in the control group were also tested negative for HAV RNA. HAV viremia was correlated to ALT peak (r = .64; P < .0001). HIV-infected patients have similar HAV RNA levels but were less likely to have prolonged international normalized ratio of prothrombin time when compared to the HIV-uninfected group (P = .016), suggesting a less severe course of acute hepatitis. HAV RNA was detected in the serum of most of the patients with acute hepatitis A, indicating that the direct detection of HAV can be used to confirm hepatitis A in patients tested positive for anti-HAV IgM antibodies. Nucleic acid tests should serve more broadly during the diagnosis workup of acute hepatitis A to improve the predictive values of HAV in vitro diagnostic tests and to confirm acute hepatitis A in patients tested positive with IgM with moderate or low S/CO values.


Assuntos
Hepatite A/diagnóstico , RNA Viral/sangue , Testes Diagnósticos de Rotina , Surtos de Doenças , França , Hepatite A/epidemiologia , Anticorpos Anti-Hepatite A/sangue , Humanos , Imunoglobulina M/sangue
8.
J Clin Lab Anal ; 33(3): e22719, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30474140

RESUMO

BACKGROUND: Little is known about the involvement of herpes simplex virus (HSV) or Mycobacterium tuberculosis (MTB) as potentially curable causes of central nervous system (CNS) infections in sub-Saharan Africa. OBJECTIVE: In this study, we developed a PCR assay dedicated to simultaneous testing of HSV1/HSV2 and MTB in Burkina Faso, a country where HSV is neglected as a cause of CNS infection and where TB prevalence is high. METHODS: A consensus HSV1/HSV2 set of primers and probe were designed and combined to primers and probe targeting the IS6110 repetitive insertion sequence of MTB. Analytical performances of the assay were evaluated on reference materials. Cerebrospinal fluid (CSF) collected from subjects with aseptic meningitis was tested for HSV1/HSV2 and MTB DNA. RESULTS: The UL29 gene was chosen as a highly conserved region targeted by the HSV1/HSV2 nucleic acid test. The lower limits of detection were estimated to be 2.45 copies/µL for HSV1, 1.72 copies/µL for HSV2, and 2.54 IS6110 copies per µL for MTB. The PCR was used in 202 CSF collected from subjects suspected of aseptic meningitis. Five samples (2.46%) tested positive, including two children positive for HSV1 (0.99%) and three adults tested positive for MTB (1.47%). CONCLUSION: Using an in-house real-time PCR assay, we showed that both HSV and MTB are etiologic pathogens contributing to aseptic meningitis in Burkina Faso. This molecular test may have clinical utility for early diagnosis for those treatable CNS infections.


Assuntos
DNA Bacteriano/líquido cefalorraquidiano , DNA Viral/líquido cefalorraquidiano , Herpes Simples/diagnóstico , Meningite Asséptica/diagnóstico , Tipagem Molecular/métodos , Tuberculose Meníngea/diagnóstico , Adulto , Burkina Faso , Criança , Herpesvirus Humano 1/genética , Herpesvirus Humano 2/genética , Humanos , Limite de Detecção , Meningite Asséptica/microbiologia , Meningite Asséptica/virologia , Mycobacterium tuberculosis/genética
10.
J Transl Med ; 16(1): 296, 2018 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-30359283

RESUMO

BACKGROUND: Subclinical mastitis (SCM) is relatively common in lactating women and may be associated with HIV shedding in breast milk. The potential association between HIV infection and breast milk immunologic factors and immune response to SCM needs to be addressed. METHODS: In this cross-sectional study, SCM (Na/K ratio > 1) was tested in 165 mature breast milk samples collected from 40 HIV-infected women who didn't transmit HIV to their child by breastfeeding and 43 HIV-uninfected women enrolled in an interventional cohort in South-Africa (Vertical Transmission Study). The level of 33 immune markers related to Th1/Th2 related response, inflammation and bacterial exposure were compared in ART-naive HIV-infected versus HIV-uninfected women. The associations between HIV infection and SCM on the concentration of immune factors were tested separately by Wilcoxon rank-sum test and corrected for false discovery rate. To control for potential confounder effects and take into account the clustering of breast milk samples from a single woman, multivariate mixed linear models adjusted on child age at the time of sampling were performed for each immune factor. RESULTS: Subclinical mastitis was detected in 15 (37.5%) HIV-infected women and 10 (23.3%) HIV-uninfected women. In the absence of SCM, the breast milk levels of IP-10 and MIG were higher and IL1-RA lower in HIV-infected women than in HIV-uninfected women (respectively p < 0.001, p = 0.001, p = 0.045). In HIV-uninfected women, SCM was characterized by a robust immune response with higher concentrations of a broad panel of Th1 and inflammatory related immune markers than in samples without SCM. By contrast, in HIV-infected women a limited number of immune markers were increased and lower increases were observed in samples with SCM than without SCM. CONCLUSION: HIV infection in ART-naïve women was associated with elevated breast milk levels of IP-10 and MIG, which areTh1-related cytokines induced by IFN-γ. During SCM, a lower and narrower immune response was observed in HIV-infected than HIV-uninfected women, suggesting that HIV infection affects the capacity of the mammary gland to respond to SCM.


Assuntos
Infecções por HIV/complicações , Mastite/complicações , Mastite/imunologia , Adolescente , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Leite Humano/imunologia , Estatísticas não Paramétricas , Adulto Jovem
11.
Bull World Health Organ ; 96(11): 750-759, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30455530

RESUMO

OBJECTIVE: To estimate population-wide hepatitis B and C seroprevalence using dried blood spot samples acquired for human immunodeficiency virus (HIV) surveillance as part of the 2010-2011 Demographic and Health Survey in Burkina Faso. METHODS: We used the database acquired during the multistage, clustered, population-based survey, in which 15 377 participants completed questionnaires and provided dried blood spot samples for HIV testing. We extracted sociodemographic and geographic data including age, sex, ethnicity, education, wealth, marital status and region for each participant. We performed hepatitis B and C assays on 14 886 HIV-negative samples between March to October 2015, and calculated weighted percentages of hepatitis seroprevalence for each variable. FINDINGS: We estimated seroprevalence as 9.1% (95% confidence interval, CI: 8.5-9.7) for the hepatitis B surface antigen and 3.6% (95% CI: 3.3-3.8) for hepatitis C virus antibodies, classifying Burkina Faso as highly endemic for hepatitis B and low-intermediate for hepatitis C. The seroprevalence of hepatitis was higher in men than in women, and varied significantly for both with age, education, ethnicity and region. Extremely high HCV-Ab seroprevalence (13.2%; 95% CI: 10.6-15.7) was identified in the Sud-Ouest region, in particular within the youngest age group (15-20 years), indicating an ongoing epidemic. CONCLUSION: Our population-representative hepatitis seroprevalence estimates in Burkina Faso advocate for the inclusion of hepatitis serological tests and risk factor questionnaire items in future surveys, the results of which are crucial for the development of appropriate health policies and infection control programmes.


Assuntos
Hepatite B/epidemiologia , Hepatite C/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Burkina Faso/epidemiologia , Estudos Transversais , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Características de Residência , Fatores de Risco , Estudos Soroepidemiológicos , Distribuição por Sexo , Fatores Socioeconômicos , Adulto Jovem
12.
BMC Infect Dis ; 18(1): 622, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30514229

RESUMO

BACKGROUND: Nucleic acid tests performed on blood samples collected on Dried Blood Spot (DBS) and detection of HCV core antigen (HCVcAg) are two approaches that may facilitate access to HCV diagnosis in low and middle incomes countries. In this study we evaluate HCV RNA and HCV antigen testing on DBS in HIV/HCV co-infected peoples who inject drugs in Vietnam. METHOD: One hundred and four HIV/HCV seropositive patients managed in outpatient care at the Haiphong Viet Tiep hospital were included in this study from February to March, 2014 (ANRS 12262 study). RESULTS: Eighty-six subjects were tested positive for HCV RNA in serum, median (IQR): 6.9 log10 IU/ml (5.6-7.4 log10 IU/ml). Genotypes consisted of 57 G1 (69%), 3 G3 (4%), and 22 G6 (27%). HCV RNA was detected on DBS specimens in 79 out 86 subjects with chronic hepatitis C (sensitivity 92.5%; 95% CI: 85.1-96.9%). HCV RNA level on DBS and serum was moderately correlated (r = 0.24; p = 0.05) suggesting a degradation of HCV RNA due to transportation and storage conditions. HCVcAg was detected in 75/86 dB specimens (sensitivity: 87.2%; 95% CI: 78.3-93.4%), with a strong positive relationship between DBS HCVcAg and serum HCV RNA levels (r = 0.80; P < 0.0001). CONCLUSIONS: Quantification of HCVcAg on DBS appears to benefit from substantial stability under prolonged storage conditions but with a lower analytical sensitivity compared to DBS HCV RNA testing. Detection of HCV RNA on DBS is an interesting approach for confirming viral replication in HCV seropositive persons but the impact of pre-analytical conditions on the integrity of HCV RNA needs to be controlled.


Assuntos
Teste em Amostras de Sangue Seco/métodos , Infecções por HIV/virologia , Hepatite C/virologia , RNA Viral/análise , Abuso de Substâncias por Via Intravenosa/virologia , Proteínas do Core Viral/análise , Viremia/diagnóstico , Adulto , Coinfecção , Estudos Transversais , Testes Diagnósticos de Rotina , Usuários de Drogas , Feminino , Genótipo , HIV/genética , Infecções por HIV/sangue , Infecções por HIV/complicações , Hepacivirus/genética , Hepatite C/sangue , Hepatite C/complicações , Hepatite C/diagnóstico , Humanos , Testes Imunológicos , Injeções , Masculino , RNA Viral/sangue , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Abuso de Substâncias por Via Intravenosa/sangue , Abuso de Substâncias por Via Intravenosa/complicações , Vietnã , Proteínas do Core Viral/sangue , Proteínas do Core Viral/genética , Viremia/sangue , Viremia/genética
14.
J Clin Microbiol ; 54(6): 1641-1643, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27008874

RESUMO

The impact of HIV-1 DNA coamplification during HIV-1 RNA quantification on dried blood spots (DBS) was explored. False-positive HIV RNA detection (22/62, 35%) was associated with high HIV-1 DNA levels. Specificity of HIV-1 RNA assays on DBS should be evaluated following manufacturer protocols on samples with HIV-1 DNA levels of ≥1,000 copies/10(6) peripheral blood mononuclear cells.


Assuntos
DNA Viral/sangue , Erros de Diagnóstico , Infecções por HIV/virologia , HIV-1/isolamento & purificação , RNA Viral/sangue , Manejo de Espécimes/métodos , Carga Viral/métodos , Dessecação , Monitoramento de Medicamentos/métodos , Reações Falso-Positivas , Infecções por HIV/tratamento farmacológico , Humanos
15.
Blood ; 122(17): 3030-3, 2013 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-23940281

RESUMO

A high prevalence of monoclonal gammopathy (MG) has been observed in HIV-infected patients. We explored the conditions associated with long-term persistence of serum monoclonal protein (M protein) in HIV-infected patients on antiretroviral therapy (ART). Of 21 patients with MG, M protein disappeared in 12 patients (58%) over 5 years of ART. Higher level of serum γ-globulin and higher percentages of circulating plasmablasts and plasma cells were observed in patients with persistent MG compared with patients with transient MG. MG persistence was associated with the cumulative time of detectable plasma HIV RNA after ART initiation, detection of Epstein-Barr virus (EBV) DNA in plasma, and a high level of EBV DNA in B cells. Poor control of HIV replication and detectable EBV replication in plasma were both associated with long-term MG persistence in patients on ART. In the case of viral control, MG associated with HIV infection is usually transient.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade , DNA Viral/antagonistas & inibidores , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Infecções por HIV/tratamento farmacológico , Paraproteinemias/tratamento farmacológico , Replicação Viral/efeitos dos fármacos , Adulto , Coinfecção , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/virologia , Feminino , Glicoproteínas/sangue , Glicoproteínas/genética , Glicoproteínas/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , Herpesvirus Humano 4/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Paraproteinemias/imunologia , Paraproteinemias/virologia , Plasmócitos/efeitos dos fármacos , Plasmócitos/imunologia , Plasmócitos/virologia , Fatores de Tempo , Carga Viral/efeitos dos fármacos , gama-Globulinas/genética , gama-Globulinas/imunologia
16.
J Med Virol ; 86(1): 30-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24114930

RESUMO

Individuals infected with HIV have higher circulating Epstein-Barr virus (EBV) DNA load compared to healthy carriers. This study investigated whether level of spontaneous immunoglobulin secreting cells, one of the major hallmarks of HIV infection, is associated with an increase of EBV DNA load in PBMCs and the spontaneous EBV lytic cycle ex vivo in patients infected with HIV. Spontaneous virus production by cells infected with EBV and EBV DNA loads in PBMCs from which CD8(+) T-cells were removed were measured in 20 HIV-aviremic and 14 HIV-viremic patients. The number of circulating immunoglobulin-secreting cells (Ig-SCs) and CD8(+) T-lymphocyte activation were also investigated. Patients with detectable HIV RNA in plasma exhibited higher spontaneous ex vivo EBV secretion and higher levels of EBV DNA in PBMCs than their aviremic counterparts. In the two groups observed, a positive correlation was found between PBMCs EBV DNA viral load and Ig-SCs, CD38(bright) expression on CD8(+) T-cells and EBV DNA load in cell culture supernatants. These findings suggest that B-cell polyclonal activation and B-cell terminal differentiation into Ig-SCs may fuel EBV DNA reservoir and promote EBV production ex vivo in patients infected with HIV.


Assuntos
Células Produtoras de Anticorpos/imunologia , Infecções por Vírus Epstein-Barr/virologia , Infecções por HIV/complicações , Infecções por HIV/imunologia , Herpesvirus Humano 4/isolamento & purificação , Carga Viral , Adulto , Células Cultivadas , DNA Viral/análise , DNA Viral/genética , Feminino , HIV/isolamento & purificação , Humanos , Leucócitos Mononucleares/virologia , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue
17.
J Med Virol ; 86(5): 851-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24265067

RESUMO

Epstein-Barr virus (EBV) genome quantitation in whole blood is used widely for therapeutic monitoring of EBV-associated disorders in immunosuppressed individuals and in patients with EBV-associated lymphoma. However, the most appropriate biological material to be used for EBV DNA quantitation remains a subject of debate. This study compare the detection rate and levels of EBV DNA from whole blood, plasma, enriched B-cells, and B-cell short-term culture supernatant using quantitative real-time PCR. Samples were collected from 33 subjects with either HIV infection or B-cell lymphoma. Overall, EBV DNA was detected in 100% of enriched B-cell samples, in 82% of B-cell culture supernatants, in 57% of plasma, and 42% of whole blood samples. A significant correlation for EBV viral load was found between enriched B-cell and B-cell culture supernatant material (ρ = 0.92; P < 0.0001), but no significant correlation existed between EBV DNA levels in whole blood and enriched B-cells (ρ = -0.02; P = 0.89), whole blood and plasma (ρ = 0.24; P = 0.24), or enriched B-cells and plasma (ρ = 0.08; P = 0.77). Testing of enriched B-cells appeared to be the most sensitive method for detection of EBV DNA as well as for exploration of the cellular reservoir. Quantitation of EBV DNA in plasma and B-cell culture supernatant may be of interest to assess EBV reactivation dynamics and response to treatment as well as to decipher EBV host-pathogen interactions in various clinical scenarios.


Assuntos
Linfócitos B/virologia , Sangue/virologia , Técnicas de Laboratório Clínico/métodos , DNA Viral/isolamento & purificação , Infecções por Vírus Epstein-Barr/diagnóstico , Infecções por Vírus Epstein-Barr/virologia , Carga Viral , Técnicas de Cultura de Células , Meios de Cultura , Monitoramento de Medicamentos/métodos , Infecções por HIV/complicações , Humanos , Linfoma de Células B/virologia , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade , Virologia/métodos
18.
Am J Trop Med Hyg ; 110(1): 127-132, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38011730

RESUMO

Leptospirosis is presumably an important cause of non-malarial fever in West Africa. In this study, outpatients consulting in primary care clinics during the rainy season were tested for leptospirosis, and clinical characteristics associated with leptospirosis cases were explored. Patients with fever ≥ 39°C were recruited in nine primary health care centers in Bobo Dioulasso (Burkina Faso). Diagnosis of malaria was ruled out using a rapid diagnostic test (RDT; SD Bioline Malaria®). Leptospirosis cases were defined as patients who tested positive for Leptospira IgM (Leptocheck-WB RDT and Leptospira IgM ELISA assay, Panbio) or DNA in plasma (LipL32 polymerase chain reaction [PCR]). Among 350 patients, 202 tested positive for malaria and were excluded, and 148 met the eligibility criteria and were included. Among these, 26 subjects were considered to be leptospirosis cases: 23 tested positive for Leptospira IgM (15.5%) and three tested positive by PCR (2.2%). Headaches, abdominal symptoms, and myalgia were frequently reported without any difference between leptospirosis cases and negative cases. Cough was more frequently observed among subjects testing positive for leptospirosis (P = 0.02). Water exposure, presence of a skin injury, and walking barefoot were associated with a Leptospira-positive test. All leptospirosis cases recovered without sequelae. A significant portion of outpatients with non-malarial febrile illness during the rainy season in Burkina Faso had epidemiological factors associated with leptospirosis and tested positive for Leptospira. The favorable outcome of leptospirosis cases was reassuring; this could be due in particular to the young age of the patients.


Assuntos
Leptospira , Leptospirose , Malária , Humanos , Burkina Faso/epidemiologia , Pacientes Ambulatoriais , Estações do Ano , Leptospirose/diagnóstico , Leptospirose/epidemiologia , Malária/diagnóstico , Malária/epidemiologia , Leptospira/genética , Anticorpos Antibacterianos , Imunoglobulina M , Atenção Primária à Saúde
19.
Artigo em Inglês | MEDLINE | ID: mdl-38735369

RESUMO

OBJECTIVES: Widespread testing and treatment are essential to eliminate hepatitis B virus (HBV) infection as a public health concern. However, in resource-limited countries, access to HBV PCR is limited. In this study, we developed a quantitative HBV PCR assay on open molecular platforms and evaluate its performance in diagnosing clinically significant HBV DNA thresholds as defined by the WHO (2000 IU/mL, 20 000 IU/mL, and 200 000 IU/mL). METHODS: We implemented our HBV PCR test in seven African and Asian countries and France, using either an in-house laboratory method or a European conformity for in vitro diagnostic (CE-IVD) marked version of the PCR (Generic HBV Charge Virale, Biocentric). Results were compared with reference tests (Roche Cobas AmpliPrep/Cobas TaqMan and Abbott RealTime on Abbott m2000). RESULTS: There was a good agreement between the HBV DNA results of 1015 samples tested by the PCR on open polyvalent platforms and the results from reference tests (mean difference (bias ± standard deviation [SD]): -0.3 ± 0.7 log10 IU/mL and -0.2 ± 0.9 log10 IU/mL when compared with Roche and Abbott tests, respectively). Kappa-Cohen agreements between the HBV PCR on open polyvalent platforms and the Roche/Abbott assays appeared almost perfect for HBV DNA levels ranged from >20 000 to 200 000 IU/mL and >200 000 IU/mL, substantial and moderate for HBV DNA levels ranged from 2000 to 20 000 IU/mL when compared with Abbott and Roche, respectively. The assay's performance was consistent across genotypes A, B, C, D, and E. DISCUSSION: This field evaluation showed that our HBV PCR test is a valuable alternative to proprietary PCR systems. PCR assays on open platforms contribute to expanding clinical laboratory solutions for diagnosing individuals who meet the viral load criteria for antiviral therapy (>20 000 IU/mL) and mother-to-child prophylaxis (>200 000 IU/mL).

20.
J Clin Immunol ; 33(1): 22-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22914896

RESUMO

BACKGROUND: Despite the use of combined antiretroviral therapy, HIV-infected individuals have a higher risk of developing B-cell lymphoma compared to the general population. We aim to explore whether lymphocyte activation, increase in Th1 response as well as markers of EBV reactivation, may precede lymphoma diagnosis. METHODS: Thirteen cases and 26 controls matched on CD4(+) T-cell count and HIV plasma viral load were identified. Samples were collected 0 to 5 years prior to B-cell lymphoma diagnosis. Seven out of 13 (54 %) and 16/26 (61.5 %) of cases and controls were receiving antiretroviral therapy at the time of sampling, respectively. CD8(+) T-cell activation and Th1 cytokine concentrations were measured before lymphoma onset, together with IgG antibodies directed against viral capsid antigen (VCA) and serum levels of EBV DNA. RESULTS: A higher level of CD8(+) T-cell activation was observed in patients developing lymphoma. Four out of seven Th1 cytokine serum concentrations were significantly higher in patients with lymphoma than in the control group: IL-2R, IL-12p40/70, IFN-γ-inducible protein 10 (IP-10) and monokine induced by IFN-γ (MIG). Anti-VCA IgG level were significantly higher in cases than in controls. Four cases (30 %) but no controls had detectable EBV DNA in serum. CONCLUSION: A higher level of T-cell activation, Th1 cytokine serum concentration and markers of EBV replication, preceded B-cell lymphoma diagnosis. This may suggest that viral antigen stimulation is associated with the genesis of lymphoma in HIV-infected patients.


Assuntos
Linfoma de Burkitt/imunologia , Citocinas/metabolismo , Doença de Hodgkin/imunologia , Ativação Linfocitária/imunologia , Subpopulações de Linfócitos T/imunologia , Células Th1/imunologia , Células Th1/virologia , Regulação para Cima/imunologia , Adulto , Linfoma de Burkitt/diagnóstico , Linfoma de Burkitt/virologia , Estudos de Casos e Controles , Comorbidade , Citocinas/biossíntese , Infecções por HIV/imunologia , Infecções por HIV/metabolismo , Infecções por HIV/patologia , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/imunologia , Doença de Hodgkin/diagnóstico , Doença de Hodgkin/virologia , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/virologia , Células Th1/metabolismo
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