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1.
Nature ; 596(7871): 276-280, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34237773

RESUMO

The SARS-CoV-2 B.1.617 lineage was identified in October 2020 in India1-5. Since then, it has become dominant in some regions of India and in the UK, and has spread to many other countries6. The lineage includes three main subtypes (B1.617.1, B.1.617.2 and B.1.617.3), which contain diverse mutations in the N-terminal domain (NTD) and the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein that may increase the immune evasion potential of these variants. B.1.617.2-also termed the Delta variant-is believed to spread faster than other variants. Here we isolated an infectious strain of the Delta variant from an individual with COVID-19 who had returned to France from India. We examined the sensitivity of this strain to monoclonal antibodies and to antibodies present in sera from individuals who had recovered from COVID-19 (hereafter referred to as convalescent individuals) or who had received a COVID-19 vaccine, and then compared this strain with other strains of SARS-CoV-2. The Delta variant was resistant to neutralization by some anti-NTD and anti-RBD monoclonal antibodies, including bamlanivimab, and these antibodies showed impaired binding to the spike protein. Sera collected from convalescent individuals up to 12 months after the onset of symptoms were fourfold less potent against the Delta variant relative to the Alpha variant (B.1.1.7). Sera from individuals who had received one dose of the Pfizer or the AstraZeneca vaccine had a barely discernible inhibitory effect on the Delta variant. Administration of two doses of the vaccine generated a neutralizing response in 95% of individuals, with titres three- to fivefold lower against the Delta variant than against the Alpha variant. Thus, the spread of the Delta variant is associated with an escape from antibodies that target non-RBD and RBD epitopes of the spike protein.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/imunologia , COVID-19/virologia , Convalescença , Evasão da Resposta Imune/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/epidemiologia , Vacinas contra COVID-19/administração & dosagem , Epitopos/química , Epitopos/genética , Epitopos/imunologia , França , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética
2.
Clin Infect Dis ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38193816

RESUMO

DTG/3TC has a high genetic barrier against the development of HIV drug resistance. We report two cases of R263K + M184 V mutations during DTG/3TC failure followed by viral suppression after adherence intervention without treatment change that we attribute to residual drug activity, reduced viral fitness, and robust immune competence.

3.
Small ; : e2404167, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39011971

RESUMO

Nucleic acids are important biomarkers in cancer and viral diseases. However, their ultralow concentration in biological/clinical samples makes direct target detection challenging, because it leads to slow hybridization kinetics with the probe and its insufficient signal-to-noise ratio. Therefore, RNA target detection is done by molecular (target) amplification, notably by RT-PCR, which is a tedious multistep method that includes nucleic acid extraction and reverse transcription. Here, a direct method based on ultrabright dye-loaded polymeric nanoparticles in a sandwich-like hybridization assay with magnetic beads is reported. The ultrabright DNA-functionalized nanoparticle, equivalent to ≈10 000 strongly emissive rhodamine dyes, is hybridized with the magnetic bead to the RNA target, providing the signal amplification for the detection. This concept (magneto-fluorescent sandwich) enables high-throughput detection of DNA and RNA sequences of varied lengths from 48 to 1362 nt with the limit of detection down to 0.3 fm using a plate reader (15 zeptomoles), among the best reported for optical sandwich assays. Moreover, it allows semi-quantitative detection of SARS-CoV-2 viral RNA directly in clinical samples without a dedicated RNA extraction step. The developed technology, combining ultrabright nanoparticles with magnetic beads, addresses fundamental challenges in RNA detection; it is expected to accelerate molecular diagnostics of diseases.

4.
Emerg Infect Dis ; 29(3): 669-671, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36823716

RESUMO

We report a case of severe tick-borne encephalitis in a pregnant woman, leading to a prolonged stay in the intensive care unit. She showed minor clinical improvement >6 months after her presumed infection. The patient was not vaccinated, although an effective vaccine is available and not contraindicated during pregnancy.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos , Vacinas , Humanos , Feminino , Gravidez , Gestantes
5.
J Med Virol ; 95(7): e28936, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37404001

RESUMO

Transplant recipients display poor responses to SARS-CoV-2 mRNA vaccines. In this retrospective study, we investigate torque teno virus (TTV) viral load (VL), a ubiquitous virus reflecting global immune response levels, as a predictive factor of vaccine response in kidney transplant recipients (KTR). Four hundred and fifty-nine KTR having received two SARS-CoV-2 mRNA vaccine doses were enrolled, and 241 of them subsequently received a third vaccine dose. Antireceptor-binding domain (RBD) IgG response was assessed after each vaccine dose and TTV VL was measured in pre-vaccine samples. Prevaccine TTV VL > 6.2 log10 copies (cp)/mL was independently associated with nonresponse to two doses (odds ratio (OR) = 6.17, 95% confidence interval (CI95) = 2.42-15.78) as well as to three doses (OR = 3.62, 95% CI95 = 1.55-8.49). In nonresponders to the second dose, high TTV VL in prevaccine samples or measured before the third dose were equally predictive of lower seroconversion rates and antibody titers. High TTV VL before and during SARS-CoV-2 vaccination schedules are predictive of poor vaccine response in KTR. This biomarker should be further evaluated regarding other vaccine responses.


Assuntos
COVID-19 , Transplante de Rim , Torque teno virus , Humanos , Torque teno virus/genética , Vacinas contra COVID-19 , Transplantados , Carga Viral , Estudos Retrospectivos , COVID-19/prevenção & controle , SARS-CoV-2 , Anticorpos Antivirais
6.
J Neuroradiol ; 50(5): 470-481, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36657613

RESUMO

BACKGROUND AND PURPOSE: Cerebral hypoperfusion has been reported in patients with COVID-19 and neurological manifestations in small cohorts. We aimed to systematically assess changes in cerebral perfusion in a cohort of 59 of these patients, with or without abnormalities on morphological MRI sequences. METHODS: Patients with biologically-confirmed COVID-19 and neurological manifestations undergoing a brain MRI with technically adequate arterial spin labeling (ASL) perfusion were included in this retrospective multicenter study. ASL maps were jointly reviewed by two readers blinded to clinical data. They assessed abnormal perfusion in four regions of interest in each brain hemisphere: frontal lobe, parietal lobe, posterior temporal lobe, and temporal pole extended to the amygdalo-hippocampal complex. RESULTS: Fifty-nine patients (44 men (75%), mean age 61.2 years) were included. Most patients had a severe COVID-19, 57 (97%) needed oxygen therapy and 43 (73%) were hospitalized in intensive care unit at the time of MRI. Morphological brain MRI was abnormal in 44 (75%) patients. ASL perfusion was abnormal in 53 (90%) patients, and particularly in all patients with normal morphological MRI. Hypoperfusion occurred in 48 (81%) patients, mostly in temporal poles (52 (44%)) and frontal lobes (40 (34%)). Hyperperfusion occurred in 9 (15%) patients and was closely associated with post-contrast FLAIR leptomeningeal enhancement (100% [66.4%-100%] of hyperperfusion with enhancement versus 28.6% [16.6%-43.2%] without, p = 0.002). Studied clinical parameters (especially sedation) and other morphological MRI anomalies had no significant impact on perfusion anomalies. CONCLUSION: Brain ASL perfusion showed hypoperfusion in more than 80% of patients with severe COVID-19, with or without visible lesion on conventional MRI abnormalities.


Assuntos
COVID-19 , Masculino , Humanos , Pessoa de Meia-Idade , Marcadores de Spin , COVID-19/complicações , Imageamento por Ressonância Magnética , Perfusão , Circulação Cerebrovascular
7.
Am J Transplant ; 22(11): 2675-2681, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35713984

RESUMO

The cilgavimab-tixagevimab combination retains a partial in vitro neutralizing activity against the current SARS-CoV-2 variants of concern (omicron BA.1, BA.1.1, and BA.2). Here, we examined whether preexposure prophylaxis with cilgavimab-tixagevimab can effectively protect kidney transplant recipients (KTRs) against the omicron variant. Of the 416 KTRs who received intramuscular prophylactic injections of 150 mg tixagevimab and 150 mg cilgavimab, 39 (9.4%) developed COVID-19. With the exception of one case, all patients were symptomatic. Hospitalization and admission to an intensive care unit were required for 14 (35.9%) and three patients (7.7%), respectively. Two KTRs died of COVID-19-related acute respiratory distress syndrome. SARS-CoV-2 sequencing was carried out in 15 cases (BA.1, n = 5; BA.1.1, n = 9; BA.2, n = 1). Viral neutralizing activity of the serum against the BA.1 variant was negative in the 12 tested patients, suggesting that this prophylactic strategy does not provide sufficient protection against this variant of concern. In summary, preexposure prophylaxis with cilgavimab-tixagevimab at the dose of 150 mg of each antibody does not adequately protect KTRs against omicron. Further clarification of the optimal dosing can assist in our understanding of how best to harness its protective potential.


Assuntos
COVID-19 , Transplante de Rim , Humanos , SARS-CoV-2 , Transplante de Rim/efeitos adversos , Anticorpos Neutralizantes , Anticorpos Antivirais
8.
J Infect Dis ; 223(4): 600-609, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33249438

RESUMO

BACKGROUND: Neurological manifestations are common in patients with coronavirus disease 2019 (COVID-19), but little is known about pathophysiological mechanisms. In this single-center study, we examined neurological manifestations in 58 patients, including cerebrospinal fluid (CSF) analysis and neuroimaging findings. METHODS: The study included 58 patients with COVID-19 and neurological manifestations in whom severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse-transcription polymerase chain reaction screening and on CSF analysis were performed. Clinical, laboratory, and brain magnetic resonance (MR) imaging data were retrospectively collected and analyzed. RESULTS: Patients were mostly men (66%), with a median age of 62 years. Encephalopathy was frequent (81%), followed by pyramidal dysfunction (16%), seizures (10%), and headaches (5%). CSF protein and albumin levels were increased in 38% and 23%, respectively. A total of 40% of patients displayed an elevated albumin quotient, suggesting impaired blood-brain barrier integrity. CSF-specific immunoglobulin G oligoclonal band was found in 5 patients (11%), suggesting an intrathecal synthesis of immunoglobulin G, and 26 patients (55%) presented identical oligoclonal bands in serum and CSF. Four patients (7%) had a positive CSF SARS-CoV-2 reverse-transcription polymerase chain reaction. Leptomeningeal enhancement was present on brain MR images in 20 patients (38%). CONCLUSIONS: Brain MR imaging abnormalities, especially leptomeningeal enhancement, and increased inflammatory markers in CSF are frequent in patients with neurological manifestations related to COVID-19, whereas SARS-CoV-2 detection in CSF remained scanty.


Assuntos
Encefalopatias/líquido cefalorraquidiano , Encéfalo/diagnóstico por imagem , COVID-19/complicações , Idoso , Biomarcadores/líquido cefalorraquidiano , Barreira Hematoencefálica/diagnóstico por imagem , Barreira Hematoencefálica/patologia , Encefalopatias/diagnóstico por imagem , Encefalopatias/virologia , COVID-19/líquido cefalorraquidiano , COVID-19/diagnóstico por imagem , Feminino , França , Humanos , Inflamação/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
J Infect Dis ; 224(6): 983-988, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-33693749

RESUMO

We measured anti-spike (S), nucleoprotein (N), and neutralizing antibodies in sera from 308 healthcare workers with a positive reverse-transcription quantitative polymerase chain reaction result for severe acute respiratory syndrome coronavirus 2 and with mild disease, collected at 2 timepoints up to 6 months after symptom onset. At month 1, anti-S and -N antibody levels were higher in male participants aged >50 years and participants with a body mass index (BMI) >25 kg/m2. At months 3-6, anti-S and anti-N antibodies were detected in 99% and 59% of individuals, respectively. Anti-S antibodies and neutralizing antibodies declined faster in men than in women, independent of age and BMI, suggesting an association of sex with evolution of the humoral response.


Assuntos
Anticorpos Neutralizantes/sangue , COVID-19/imunologia , Caracteres Sexuais , Adulto , Anticorpos Antivirais/sangue , Feminino , Células HEK293 , Pessoal de Saúde , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/imunologia
10.
J Infect Dis ; 224(9): 1489-1499, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34282461

RESUMO

BACKGROUND: Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces a complex antibody response that varies by orders of magnitude between individuals and over time. METHODS: We developed a multiplex serological test for measuring antibodies to 5 SARS-CoV-2 antigens and the spike proteins of seasonal coronaviruses. We measured antibody responses in cohorts of hospitalized patients and healthcare workers followed for up to 11 months after symptoms. A mathematical model of antibody kinetics was used to quantify the duration of antibody responses. Antibody response data were used to train algorithms for estimating time since infection. RESULTS: One year after symptoms, we estimate that 36% (95% range, 11%-94%) of anti-Spike immunoglobulin G (IgG) remains, 31% (95% range, 9%-89%) anti-RBD IgG remains, and 7% (1%-31%) of anti-nucleocapsid IgG remains. The multiplex assay classified previous infections into time intervals of 0-3 months, 3-6 months, and 6-12 months. This method was validated using data from a seroprevalence survey in France, demonstrating that historical SARS-CoV-2 transmission can be reconstructed using samples from a single survey. CONCLUSIONS: In addition to diagnosing previous SARS-CoV-2 infection, multiplex serological assays can estimate the time since infection, which can be used to reconstruct past epidemics.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/sangue , COVID-19/imunologia , Testes Sorológicos/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Formação de Anticorpos , Especificidade de Anticorpos , COVID-19/epidemiologia , Feminino , França/epidemiologia , Humanos , Imunoglobulina G/sangue , Cinética , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/imunologia , Sensibilidade e Especificidade , Estudos Soroepidemiológicos , Adulto Jovem
11.
Clin Infect Dis ; 73(7): e1762-e1765, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32986807

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a newly discovered virus for which remdesivir is the only antiviral available. We report the occurrence of a mutation in RdRP (D484Y) following treatment with remdesivir in a 76-year-old female with post-rituximab B-cell immunodeficiency and persistent SARS-CoV-2 viremia. A cure was achieved after supplementation with convalescent plasma.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , RNA Polimerase Dependente de RNA , Monofosfato de Adenosina/análogos & derivados , Idoso , Alanina/análogos & derivados , Linfócitos B , COVID-19/terapia , Feminino , Humanos , Imunização Passiva , Mutação , SARS-CoV-2 , Soroterapia para COVID-19
12.
Emerg Infect Dis ; 27(1)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33261718

RESUMO

We investigated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific antibodies and T-cell responses against SARS-CoV-2 and human coronavirus (HCoV) 229E and OC43 in 11 SARS-CoV-2 serodiscordant couples in Strausbourg, France, in which 1 partner had evidence of mild coronavirus disease (COVID-19) and in 10 unexposed healthy controls. Patients with confirmed COVID-19 were considered index patients and their partners close contacts. All index patients displayed positive SARS-CoV-2-specific antibody and T-cell responses that lasted up to 102 days after symptom onset. All contacts remained seronegative for SARS-CoV-2; however, 6 reported COVID-19 symptoms within a median of 7 days after their partners, and 4 of those showed a positive SARS-CoV-2-specific T-cell response against 3 or 4 SARS-CoV-2 antigens that lasted up to 93 days after symptom onset. The 11 couples and controls displayed positive T-cell responses against HCoV-229E or HCoV-OC43. These data suggest that exposure to SARS-CoV-2 can induce virus-specific T-cell responses without seroconversion.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/epidemiologia , COVID-19/transmissão , Família , SARS-CoV-2/imunologia , Linfócitos T/fisiologia , Adulto , Idoso , COVID-19/sangue , Teste para COVID-19 , Estudos de Casos e Controles , Feminino , França/epidemiologia , Humanos , Imunidade Celular , Masculino , Pessoa de Meia-Idade , Soroconversão , Testes Sorológicos
13.
Am J Transplant ; 21(8): 2871-2875, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33961334

RESUMO

The exact duration of viable SARS-CoV-2 shedding in kidney transplant recipients (KTRs) remains unclear. Here, we retrospectively investigated this issue using cell cultures of SARS-CoV-2 RT-PCR-positive nasopharyngeal samples (n = 40) obtained from 16 KTRs with symptomatic COVID-19 up to 39 days from symptom onset. A length of viable SARS-CoV-2 shedding >3 weeks from the onset of symptoms was identified in four KTRs (25%). These results suggest that a significant proportion of KTRs can shed viable SARS-CoV-2 for at least 3 weeks, which may favor the emergence of new variants. Based on these data, we recommend prolonging the isolation of KTRs with COVID-19 until negative SARS-CoV-2 RT-PCR testing.


Assuntos
COVID-19 , Transplante de Rim , Humanos , Transplante de Rim/efeitos adversos , Nasofaringe , Estudos Retrospectivos , SARS-CoV-2 , Transplantados
14.
Am J Transplant ; 21(1): 329-337, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32741096

RESUMO

BK virus (BKV) replication occurs frequently in kidney transplant recipients (KTR), potentially leading to BKV-associated nephropathy (BKVAN) and graft loss. Patients with high titers of BKV-neutralizing antibodies (NAbs) are protected against BKV replication, and intravenous immunoglobulin (IVIg) infusion can increase NAb titers. We investigated whether early IVIg administration prevents BKV replication in patients with low NAb titers (<4 log10 against the BKV-specific genotype). Based on NAb titers on the day of transplantation, KTR followed in the Strasbourg University Hospital (n = 174) were retrospectively divided into the following 3 risk categories for BKV replication: (1) patients with low NAb titers ("high-risk") who received IVIg for the first 3 posttransplant months (n = 44), (2) patients with low NAb titers ("high-risk") who did not undergo IVIg treatment (n = 41), and (3) patients with high NAb titers ("low-risk") who did not receive IVIg (n = 89). At 12 posttransplant months, the incidence of BKV viremia in the high-risk group treated with IVIg (6.8%) was similar to that observed in the low-risk group (10.1%) and markedly lower than that of the untreated high-risk group (36.6%; P < .001). Similar results were observed with regard to BKVAN. We conclude that IVIg may be a valuable strategy for preventing BKV replication.


Assuntos
Vírus BK , Transplante de Rim , Infecções por Polyomavirus , Infecções Tumorais por Vírus , Humanos , Imunoglobulinas Intravenosas , Transplante de Rim/efeitos adversos , Infecções por Polyomavirus/tratamento farmacológico , Infecções por Polyomavirus/prevenção & controle , Estudos Retrospectivos , Infecções Tumorais por Vírus/prevenção & controle , Viremia/tratamento farmacológico , Viremia/etiologia , Viremia/prevenção & controle
15.
J Antimicrob Chemother ; 76(9): 2400-2406, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34100068

RESUMO

BACKGROUND: Successful 2-drug regimens (2DRs) for HIV were made possible by the availability of drugs combining potency and tolerability with a high genetic barrier to resistance. How these deal with resistance development/re-emergence, compared with 3DRs, is thus of paramount importance. MATERIALS AND METHODS: A national survey including patients who were either naive or experienced with any 2DR or 3DR but failing integrase strand transfer inhibitor (INSTI)-containing regimens [two consecutive plasma viral load (VL) values >50 copies/mL] was conducted between 2014 and 2019. Genotypic resistance tests were interpreted with the v28 ANRS algorithm. RESULTS: Overall, 1104 patients failing any INSTI-containing regimen (2DRs, n = 207; 3DRs, n = 897) were analysed. Five hundred and seventy-seven (52.3%) patients were infected with a B subtype and 527 (47.3%) with non-B subtypes. Overall, 644 (58%) patients showed no known integrase resistance mutations at failure. In multivariate analysis, factors associated with the emergence of at least one integrase mutation were: high VL at failure (OR = 1.24 per 1 log10 copies/mL increase); non-B versus B subtype (OR = 1.75); low genotypic sensitivity score (GSS) (OR = 0.10 for GSS = 2 versus GSS = 0-0.5); and dolutegravir versus raltegravir (OR = 0.46). Although 3DRs versus 2DRs reached statistical significance in univariate analysis (OR = 0.59, P = 0.007), the variable is not retained in the final model. CONCLUSIONS: This study is one of the largest studies characterizing integrase resistance in patients failing any INSTI-containing 2DR or 3DR in routine clinical care and reveals factors associated with emergence of integrase resistance that should be taken into consideration in clinical management. No difference was evidenced between patients receiving a 2DR or a 3DR.


Assuntos
Infecções por HIV , Inibidores de Integrase de HIV , Integrase de HIV , HIV-1 , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , Integrase de HIV/genética , Inibidores de Integrase de HIV/farmacologia , Inibidores de Integrase de HIV/uso terapêutico , HIV-1/genética , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Humanos , Mutação , Piridonas , Raltegravir Potássico/uso terapêutico
16.
Eur Radiol ; 31(5): 2944-2955, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33155106

RESUMO

OBJECTIVES: To compare brain MRI findings in progressive multifocal leukoencephalopathy (PML) associated to rituximab and natalizumab treatments and HIV infection. MATERIALS AND METHODS: In this retrospective, multicentric study, we analyzed brain MRI exams from 72 patients diagnosed with definite PML: 32 after natalizumab treatment, 20 after rituximab treatment, and 20 HIV patients. We compared T2- or FLAIR-weighted images, diffusion-weighted images, T2*-weighted images, and contrast enhancement features, as well as lesion distribution, especially gray matter involvement. RESULTS: The three PML entities affect U-fibers associated with low signal intensities on T2*-weighted sequences. Natalizumab-associated PML showed a punctuate microcystic appearance in or in the vicinity of the main PML lesions, a potential involvement of the cortex, and contrast enhancement. HIV and rituximab-associated PML showed only mild contrast enhancement, punctuate appearance, and cortical involvement. The CD4/CD8 ratio showed a trend to be higher in the natalizumab group, possibly mirroring a more efficient immune response. CONCLUSION: Imaging features of rituximab-associated PML are different from those of natalizumab-associated PML and are closer to those observed in HIV-associated PML. KEY POINTS: • Nowadays, PML is emerging as a complication of new effective therapies based on monoclonal antibodies. • Natalizumab-associated PML shows more inflammatory signs, a perivascular distribution "the milky way," and more cortex involvement than rituximab- and HIV-associated PML. • MRI differences are probably related to higher levels of immunosuppression in HIV patients and those under rituximab therapy.


Assuntos
Infecções por HIV , Leucoencefalopatia Multifocal Progressiva , Encéfalo/diagnóstico por imagem , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Leucoencefalopatia Multifocal Progressiva/induzido quimicamente , Leucoencefalopatia Multifocal Progressiva/diagnóstico por imagem , Imageamento por Ressonância Magnética , Natalizumab/efeitos adversos , Estudos Retrospectivos , Rituximab/efeitos adversos
17.
Am J Transplant ; 20(11): 3162-3172, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32777130

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread widely, causing coronavirus disease 2019 (COVID-19) and significant mortality. However, data on viral loads and antibody kinetics in immunocompromised populations are lacking. We aimed to determine nasopharyngeal and plasma viral loads via reverse transcription-polymerase chain reaction and SARS-CoV-2 serology via enzyme-linked immunosorbent assay and study their association with severe forms of COVID-19 and death in kidney transplant recipients. In this study, we examined hospitalized kidney transplant recipients with nonsevere (n = 21) and severe (n = 19) COVID-19. SARS-CoV-2 nasopharyngeal and plasma viral load and serological response were evaluated based on outcomes and disease severity. Ten recipients (25%) displayed persistent viral shedding 30 days after symptom onset. The SARS-CoV-2 viral load of the upper respiratory tract was not associated with severe COVID-19, whereas the plasma viral load was associated with COVID-19 severity (P = .010) and mortality (P = .010). All patients harbored antibodies during the second week after symptom onset that persisted for 2 months. We conclude that plasma viral load is associated with COVID-19 morbidity and mortality, whereas nasopharyngeal viral load is not. SARS-CoV-2 shedding is prolonged in kidney transplant recipients and the humoral response to SARS-CoV-2 does not show significant impairment in this series of transplant recipients.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/virologia , Transplante de Rim , Pandemias , SARS-CoV-2/imunologia , Carga Viral , Idoso , COVID-19/epidemiologia , Comorbidade , Ensaio de Imunoadsorção Enzimática , Feminino , França/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/virologia , Taxa de Sobrevida/tendências
18.
J Antimicrob Chemother ; 75(1): 183-193, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31641777

RESUMO

OBJECTIVES: Patients with primary HIV-1 infection (PHI) are a particular population, giving important insight about ongoing evolution of transmitted drug resistance-associated mutation (TDRAM) prevalence, HIV diversity and clustering patterns. We describe these evolutions of PHI patients diagnosed in France from 2014 to 2016. METHODS: A total of 1121 PHI patients were included. TDRAMs were characterized using the 2009 Stanford list and the French ANRS algorithm. Viral subtypes and recent transmission clusters (RTCs) were also determined. RESULTS: Patients were mainly MSM (70%) living in the Paris area (42%). TDRAMs were identified among 10.8% of patients and rose to 18.6% when including etravirine and rilpivirine TDRAMs. Prevalences of PI-, NRTI-, first-generation NNRTI-, second-generation NNRTI- and integrase inhibitor-associated TDRAMs were 2.9%, 5.0%, 4.0%, 9.4% and 5.4%, respectively. In a multivariable analysis, age >40 years and non-R5 tropic viruses were associated with a >2-fold increased risk of TDRAMs. Regarding HIV diversity, subtype B and CRF02_AG (where CRF stands for circulating recombinant form) were the two main lineages (56% and 20%, respectively). CRF02_AG was associated with higher viral load than subtype B (5.83 versus 5.40 log10 copies/mL, P=0.004). We identified 138 RTCs ranging from 2 to 14 patients and including overall 41% from the global population. Patients in RTCs were younger, more frequently born in France and more frequently MSM. CONCLUSIONS: Since 2007, the proportion of TDRAMs has been stable among French PHI patients. Non-B lineages are increasing and may be associated with more virulent CRF02_AG strains. The presence of large RTCs highlights the need for real-time cluster identification to trigger specific prevention action to achieve better control of the epidemic.


Assuntos
Farmacorresistência Viral/genética , Monitoramento Epidemiológico , Variação Genética , Infecções por HIV/epidemiologia , HIV-1/genética , Adulto , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Evolução Molecular , Feminino , França/epidemiologia , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Filogenia , Análise de Sequência de DNA , Minorias Sexuais e de Gênero , Carga Viral , Virulência
19.
PLoS Pathog ; 14(10): e1007368, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30335851

RESUMO

Infection with human BK polyomavirus, a small double-stranded DNA virus, potentially results in severe complications in immunocompromised patients. Here, we describe the in vivo variability and evolution of the BK polyomavirus by deep sequencing. Our data reveal the highest genomic evolutionary rate described in double-stranded DNA viruses, i.e., 10(-3)-10(-5) substitutions per nucleotide site per year. High mutation rates in viruses allow their escape from immune surveillance and adaptation to new hosts. By combining mutational landscapes across viral genomes with in silico prediction of viral peptides, we demonstrate the presence of significantly more coding substitutions within predicted cognate HLA-C-bound viral peptides than outside. This finding suggests a role for HLA-C in antiviral immunity, perhaps through the action of killer cell immunoglobulin-like receptors. The present study provides a comprehensive view of viral evolution and immune escape in a DNA virus.


Assuntos
Vírus BK/genética , Antígenos HLA-C/metabolismo , Mutação , Transplante de Órgãos , Fragmentos de Peptídeos/metabolismo , Infecções por Polyomavirus/virologia , Substituição de Aminoácidos , Vírus BK/imunologia , Genoma Viral , Antígenos HLA-C/genética , Antígenos HLA-C/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Filogenia , Infecções por Polyomavirus/genética , Infecções por Polyomavirus/imunologia
20.
Am J Obstet Gynecol ; 223(6): 914.e1-914.e15, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32553908

RESUMO

BACKGROUND: Despite the mainly reassuring outcomes for pregnant women with coronavirus disease 2019 reported by previous case series with small sample sizes, some recent reports of severe maternal morbidity requiring intubation and of maternal deaths show the need for additional data about the impact of coronavirus disease 2019 on pregnancy outcomes. OBJECTIVE: This study aimed to report the maternal characteristics and clinical outcomes of pregnant women with coronavirus disease 2019. STUDY DESIGN: This retrospective, single-center study includes all consecutive pregnant women with confirmed (laboratory-confirmed) or suspected (according to the Chinese management guideline [version 7.0]) coronavirus disease 2019, regardless of gestational age at diagnosis, admitted to the Strasbourg University Hospital (France) from March 1, 2020, to April 3, 2020. Maternal characteristics, laboratory and imaging findings, and maternal and neonatal outcomes were extracted from medical records. RESULTS: The study includes 54 pregnant women with confirmed (n=38) and suspected (n=16) coronavirus disease 2019. Of these, 32 had an ongoing pregnancy, 1 had a miscarriage, and 21 had live births: 12 vaginal and 9 cesarean deliveries. Among the women who gave birth, preterm deliveries were medically indicated for their coronavirus disease 2019-related condition for 5 of 21 women (23.8%): 3 (14.3%) before 32 weeks' gestation and 2 (9.5%) before 28 weeks' gestation. Oxygen support was required for 13 of 54 women (24.1%), including high-flow oxygen (n=2), noninvasive (n=1) and invasive (n=3) mechanical ventilation, and extracorporeal membrane oxygenation (n=1). Of these, 3, aged 35 years or older with positive test result for severe acute respiratory syndrome coronavirus 2 using reverse transcription polymerase chain reaction, had respiratory failure requiring indicated delivery before 29 weeks' gestation. All 3 women were overweight or obese, and 2 had an additional comorbidity. CONCLUSION: Coronavirus disease 2019 in pregnancy was associated with maternal morbidity and preterm birth. Its association with other well-known risk factors for severe maternal morbidity in pregnant women with no infection, including maternal age above 35 years, overweight, and obesity, suggests further studies are required to determine whether these risk factors are also associated with poorer maternal outcome in these women.


Assuntos
COVID-19/complicações , Complicações Infecciosas na Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , SARS-CoV-2 , Aborto Espontâneo/epidemiologia , Adulto , COVID-19/fisiopatologia , COVID-19/terapia , Cesárea/estatística & dados numéricos , Comorbidade , Feminino , França/epidemiologia , Hospitais Universitários , Humanos , Recém-Nascido , Morbidade , Obesidade/epidemiologia , Oxigênio/administração & dosagem , Gravidez , Complicações na Gravidez/epidemiologia , Resultado da Gravidez , Respiração Artificial/estatística & dados numéricos , Estudos Retrospectivos
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