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1.
Am J Transplant ; 17(1): 161-172, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27251361

RESUMO

Kidney transplant donors are not currently implicated in predicting BK polyomavirus (BKPyV) infection in kidney transplant recipients. It has been postulated, however, that BKPyV infection originates from the kidney allograft. Because BKPyV seroreactivity correlates with BKPyV replication and thus might mirror the infectious load, we investigated whether BKPyV seroreactivity of the donor predicts viremia and BKPyV-associated nephropathy (BKPyVAN) in the recipient. In a retrospective cohort of 407 living kidney donor-recipient pairs, pretransplantation donor and recipient sera were tested for BKPyV IgG levels and correlated with the occurrence of recipient BKPyV viremia and BKPyVAN within 1 year after transplantation. Donor BKPyV IgG level was strongly associated with BKPyV viremia and BKPyVAN (p < 0.001), whereas recipient BKPyV seroreactivity showed a nonsignificant inverse trend. Pairing of high-BKPyV-seroreactive donors with low-seroreactive recipients resulted in a 10-fold increased risk of BKPyV viremia (hazard ratio 10.1, 95% CI 3.5-29.0, p < 0.001). In multivariate analysis, donor BKPyV seroreactivity was the strongest pretransplantation factor associated with viremia (p < 0.001) and BKPyVAN (p = 0.007). The proportional relationship between donor BKPyV seroreactivity and recipient infection suggests that donor BKPyV seroreactivity reflects the infectious load of the kidney allograft and calls for the use of pretransplantation BKPyV serological testing of (potential) donors and recipients.


Assuntos
Vírus BK/patogenicidade , Nefropatias/diagnóstico , Transplante de Rim/efeitos adversos , Infecções por Polyomavirus/imunologia , Infecções Tumorais por Vírus/imunologia , Viremia/diagnóstico , Feminino , Seguimentos , Taxa de Filtração Glomerular , Humanos , Nefropatias/etiologia , Testes de Função Renal , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Infecções por Polyomavirus/sangue , Infecções por Polyomavirus/virologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Transplantados , Infecções Tumorais por Vírus/sangue , Infecções Tumorais por Vírus/virologia , Viremia/etiologia
2.
Epidemiol Infect ; 144(7): 1520-7, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26554756

RESUMO

Congenital cytomegalovirus infection (cCMV) may lead to symptoms at birth and long-term consequences. We present a nationwide, retrospective cohort study on the outcome of cCMV up to age 6 years. For this study we identified cCMV, using polymerase chain reaction, by analysing dried blood spots, which are taken shortly after birth for neonatal screening. The group of children with cCMV were compared to a group of children who were cCMV negative at birth. Data were collected about their health and development up to age 6 years. Parents of 73 693 children were invited to participate, and 32 486 (44·1%) gave informed consent for testing of their child's dried blood spot for CMV. Of the 31 484 dried blood spots tested, 156 (0·5%) were positive for cCMV. Of these, four (2·6%) children had been diagnosed with cCMV prior to this study. This unique retrospective nationwide study permits the estimation of long-term sequelae of cCMV up to the age of 6 years. The birth prevalence of cCMV in this study was 0·5%, which is in line with prior estimates. Most (97·4%) children with cCMV had not been diagnosed earlier, indicating under-diagnosis of cCMV.


Assuntos
Infecções por Citomegalovirus/epidemiologia , Citomegalovirus/fisiologia , Criança , Pré-Escolar , Infecções por Citomegalovirus/virologia , Teste em Amostras de Sangue Seco , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Triagem Neonatal , Países Baixos/epidemiologia , Reação em Cadeia da Polimerase , Prevalência , Projetos de Pesquisa , Estudos Retrospectivos
3.
J Virol ; 86(5): 2676-85, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22205739

RESUMO

Enterovirus 71 (EV71) is responsible for frequent large-scale outbreaks of hand, foot, and mouth disease worldwide and represent a major etiological agent of severe, sometimes fatal neurological disease. EV71 variants have been classified into three genogroups (GgA, GgB, and GgC), and the latter two are further subdivided into subgenogroups B1 to B5 and C1 to C5. To investigate the dual roles of recombination and evolution in the epidemiology and transmission of EV71 worldwide, we performed a large-scale genetic analysis of isolates (n = 308) collected from 19 countries worldwide over a 40-year period. A series of recombination events occurred over this period, which have been identified through incongruities in sequence grouping between the VP1 and 3Dpol regions. Eleven 3Dpol clades were identified, each specific to EV71 and associated with specific subgenogroups but interspersed phylogenetically with clades of coxsackievirus A16 and other EV species A serotypes. The likelihood of recombination increased with VP1 sequence divergence; mean half-lives for EV71 recombinant forms (RFs) of 6 and 9 years for GgB and GgC overlapped with those observed for the EV-B serotypes, echovirus 9 (E9), E30, and E11, respectively (1.3 to 9.8 years). Furthermore, within genogroups, sporadic recombination events occurred, such as the linkage of two B4 variants to RF-W instead of RF-A and of two C4 variants to RF-H. Intriguingly, recombination events occurred as a founding event of most subgenogroups immediately preceding their lineage expansion and global emergence. The possibility that recombination contributed to their subsequent spread through improved fitness requires further biological and immunological characterization.


Assuntos
Enterovirus Humano A/classificação , Enterovirus Humano A/genética , Infecções por Enterovirus/virologia , Evolução Molecular , Filogenia , Recombinação Genética , Enterovirus Humano A/isolamento & purificação , Humanos , Dados de Sequência Molecular , Proteínas Virais/genética
4.
J Infect Dis ; 204(5): 777-82, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21844304

RESUMO

A retrospective nationwide study on the use of intravenous (IV) zanamivir in patients receiving intensive care who were pretreated with oseltamivir in the Netherlands was performed. In 6 of 13 patients with a sustained reduction of the viral load, the median time to start IV zanamivir was 9 days (range, 4-11 days) compared with 14 days (range, 6-21 days) in 7 patients without viral load reduction (P = .052). Viral load response did not influence mortality. We conclude that IV zanamivir as late add-on therapy has limited effectiveness. The effect of an immediate start with IV zanamivir monotherapy or in combination with other drugs need to be evaluated.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana/tratamento farmacológico , Zanamivir/uso terapêutico , Adolescente , Adulto , Pré-Escolar , Estado Terminal , Quimioterapia Combinada , Humanos , Lactente , Infusões Intravenosas , Pessoa de Meia-Idade , Países Baixos , Oseltamivir/uso terapêutico , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Carga Viral , Zanamivir/administração & dosagem
5.
J Clin Microbiol ; 49(5): 2027-30, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21367992

RESUMO

CXCL13 in cerebrospinal fluid (CSF) could be an important component for diagnosing Lyme neuroborreliosis (LNB). Levels of intrathecal CXCL13 were determined for 58 LNB patients and 210 controls; sensitivity was 88% and specificity was 89% (cutoff, 250 pg of CXCL13/ml of CSF). Elevated levels of CXCL13 can aid in the diagnosis of LNB, but levels should be interpreted with care.


Assuntos
Líquido Cefalorraquidiano/química , Quimiocina CXCL13/líquido cefalorraquidiano , Técnicas de Laboratório Clínico/métodos , Neuroborreliose de Lyme/diagnóstico , Adulto , Criança , Pré-Escolar , Diagnóstico Diferencial , Humanos , Sensibilidade e Especificidade
6.
J Virol ; 84(18): 9292-300, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20610722

RESUMO

The relationship between virus evolution and recombination in species B human enteroviruses was investigated through large-scale genetic analysis of echovirus type 9 (E9) and E11 isolates (n = 85 and 116) from 16 European, African, and Asian countries between 1995 and 2008. Cluster 1 E9 isolates and genotype D5 and A E11 isolates showed evidence of frequent recombination between the VP1 and 3Dpol regions, the latter falling into 23 (E9) and 43 (E11) clades interspersed phylogenetically with 46 3Dpol clades of E30 and with those of other species B serotypes. Remarkably, only 2 of the 112 3Dpol clades were shared by more than one serotype (E11 and E30), demonstrating an extremely large and genetically heterogeneous recombination pool of species B nonstructural-region variants. The likelihood of recombination increased with geographical separation and time, and both were correlated with VP1 divergence, whose substitution rates allowed recombination half-lives of 1.3, 9.8, and 3.1 years, respectively, for E9, E11, and E30 to be calculated. These marked differences in recombination dynamics matched epidemiological patterns of periodic epidemic cycles of 2 to 3 (E9) and 5 to 6 (E30) years and the longer-term endemic pattern of E11 infections. Phylotemporal analysis using a Bayesian Markov chain Monte Carlo method, which placed recombination events within the evolutionary reconstruction of VP1, showed a close relationship with VP1 lineage expansion, with defined recombination events that correlated with their epidemiological periodicity. Whether recombination events contribute directly to changes in transmissibility that drive epidemic behavior or occur stochastically during periodic population bottlenecks is an unresolved issue vital to future understanding of enterovirus molecular epidemiology and pathogenesis.


Assuntos
Enterovirus Humano B/classificação , Enterovirus Humano B/genética , Infecções por Enterovirus/epidemiologia , Infecções por Enterovirus/virologia , Evolução Molecular , Recombinação Genética , África/epidemiologia , Ásia/epidemiologia , Análise por Conglomerados , Enterovirus Humano B/isolamento & purificação , Europa (Continente)/epidemiologia , Genótipo , Geografia , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , RNA Viral/genética , Homologia de Sequência , Fatores de Tempo
7.
Prenat Diagn ; 31(5): 419-25, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21351281

RESUMO

In this article, we review the virology, pathology, epidemiology and clinical spectrum of intrauterine human parvovirus B19 (B19V) infection, including intrauterine fetal death, non-immune hydrops fetalis, thrombocytopenia and neurological manifestations such as pediatric stroke and perivascular calcifications. In addition, we discuss the new insights into the neurodevelopmental outcome of intrauterine B19V infection. Current diagnosis and management of B19V infection is summarized, including a diagnostic and follow-up flowchart for practical clinical use.


Assuntos
Eritema Infeccioso , Morte Fetal , Parvovirus B19 Humano/fisiologia , Complicações Infecciosas na Gravidez/diagnóstico , Adulto , Transfusão de Sangue Intrauterina , Eritema Infeccioso/epidemiologia , Eritema Infeccioso/patologia , Eritema Infeccioso/terapia , Eritema Infeccioso/virologia , Feminino , Idade Gestacional , Humanos , Hidropisia Fetal/epidemiologia , Hidropisia Fetal/patologia , Hidropisia Fetal/virologia , Doenças do Sistema Nervoso/embriologia , Doenças do Sistema Nervoso/virologia , Gravidez , Complicações Infecciosas na Gravidez/virologia , Trombocitopenia/epidemiologia , Trombocitopenia/patologia , Trombocitopenia/virologia
8.
J Virol ; 83(5): 2109-18, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19091869

RESUMO

Globally, echovirus 30 (E30) is one of the most frequently identified enteroviruses and a major cause of meningitis. Despite its wide distribution, little is known about its transmission networks or the dynamics of its recombination and geographical spread. To address this, we have conducted an extensive molecular epidemiology and evolutionary study of E30 isolates collected over 8 years from a geographically wide sample base (11 European countries, Asia, and Australia). 3Dpol sequences fell into several distinct phylogenetic groups, interspersed with other species B serotypes, enabling E30 isolates to be classified into 38 recombinant forms (RFs). Substitutions in VP1 and 3Dpol regions occurred predominantly at synonymous sites (ratio of nonsynonymous to synonymous substitutions, 0.05) with VP1 showing a rapid substitution rate of 8.3 x 10(-3) substitutions per site per year. Recombination frequency was tightly correlated with VP1 divergence; viruses differing by evolutionary distances of >0.1 (or 6 years divergent evolution) almost invariably (>97%) had different 3Dpol groups. Frequencies of shared 3Dpol groups additionally correlated with geographical distances, with Europe and South Asia showing turnover of entirely distinct virus populations. Population turnover of E30 was characterized by repeated cycles of emergence, dominance, and disappearance of individual RFs over periods of 3 to 5 years, although the existence and nature of evolutionary selection underlying these population replacements remain unclear. The occurrence of frequent "sporadic" recombinants embedded within VP1 groupings of other RFs and the much greater number of 3Dpol groups than separately identifiable VP1 lineages suggest frequent recombination with an external diverse reservoir of non-E30 viruses.


Assuntos
Infecções por Echovirus/epidemiologia , Enterovirus Humano B/genética , Evolução Molecular , Epidemiologia Molecular , Ásia/epidemiologia , Austrália/epidemiologia , DNA Viral/genética , Infecções por Echovirus/virologia , Enterovirus Humano B/classificação , Europa (Continente)/epidemiologia , Variação Genética , Genoma Viral , Geografia , Humanos , Filogenia , Recombinação Genética , Análise de Sequência de DNA , Proteínas Estruturais Virais/genética
9.
Open Forum Infect Dis ; 6(3): ofz078, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30949528

RESUMO

BACKGROUND: BK polyomavirus (BKPyV)-associated nephropathy (BKPyVAN) is a major threat for kidney transplant recipients (KTRs). The role of specific BKPyV genotypes/serotypes in development of BKPyVAN is poorly understood. Pretransplantation serotyping of kidney donors and recipients and posttransplantation genotyping of viremic recipients, could reveal the clinical relevance of specific BKPyV variants. METHODS: A retrospective cohort of 386 living kidney donor-recipient pairs was serotyped before transplantation against BKPyV genotype I-IV viral capsid protein 1 antigen, using a novel BKPyV serotyping assay. Replicating BKPyV isolates in viremic KTRs after transplantation were genotyped using real-time polymerase chain reaction and confirmed by means of sequencing. BKPyV serotype and genotype data were used to determine the source of infection and analyze the risk of viremia and BKPyVAN. RESULTS: Donor and recipient BKPyV genotype and serotype distribution was dominated by genotype I (>80%), especially Ib, over II, III and IV. Donor serotype was significantly correlated with the replicating genotype in viremic KTRs (P < .001). Individual donor and recipient serotype, serotype (mis)matching and the recipient replicating BKPyV genotype were not associated with development of viremia or BKPyVAN after transplantation. CONCLUSIONS: BKPyV donor and recipient serotyping and genotyping indicates the donor origin of replicating BKPyV in viremic KTRs but provides no evidence for BKPyV genotype-specific virulence.

10.
J Clin Virol ; 41(1): 7-12, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18065263

RESUMO

BACKGROUND: Nursing home influenza outbreaks occur in spite of established vaccination programs, and require rapid and sensitive laboratory confirmation for timely intervention. OBJECTIVES: To evaluate diagnostic approaches for rapid confirmation of nursing home influenza outbreaks. STUDY DESIGN: Influenza virus real-time PCR and Directigen Flu A+B enzyme immunoassay were performed on nasopharyngeal swabs, nasopharyngeal washes and throat swabs collected from residents with clinical suspicion of influenza during seven probable nursing home outbreaks in 2004-2005 and 2005-2006. The efficacy of specimen sampling and transport management by Public Health Service outbreak team was evaluated. RESULTS: PCR detected influenza RNA in 80% (68/85) of specimens from 81% (38/47) residents, confirming six suspected outbreaks. Immunoassay sensitivity was highest on nasopharyngeal swabs (38%; 11/29) with a positive predictive value of 100% compared to PCR. Nasopharyngeal swabs were equally sensitive to nasopharyngeal washes by PCR. Nasopharyngeal wash sampling appeared unpractical due to common underlying disability of residents. Outbreak team support was associated with a shorter time to PCR diagnosis compared to outbreaks with no logistical support (mean, 28.2h vs. 84h; P=0.05). CONCLUSIONS: Influenza real-time PCR on nasopharyngeal swabs, obtained by Public Health Service outbreak teams, enabled rapid and sensitive confirmation of nursing home influenza outbreaks.


Assuntos
Surtos de Doenças , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Orthomyxoviridae/isolamento & purificação , Idoso , Idoso de 80 Anos ou mais , Antígenos Virais/análise , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/epidemiologia , Feminino , Humanos , Técnicas Imunoenzimáticas/métodos , Masculino , Pessoa de Meia-Idade , Países Baixos , Casas de Saúde , Orthomyxoviridae/química , Orthomyxoviridae/genética , Faringe/virologia , Valor Preditivo dos Testes , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade
11.
BJOG ; 115(1): 76-81, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18053103

RESUMO

OBJECTIVE: To examine (1) the incidence of fetal thrombocytopenia in hydropic fetuses with congenital B19 virus infection, (2) the effect of intrauterine platelet transfusions and (3) the correlation between fetal B19 viral load and severity of thrombocytopenia. DESIGN: Retrospective analysis of data from prospectively collected fetal blood samples. SETTING: Leiden University Medical Centre, the national centre for management of intrauterine fetal disease in the Netherlands. POPULATION: Thirty hydropic fetuses treated with intrauterine red blood cell and platelet transfusions for human B19 virus-induced severe fetal anaemia and thrombocytopenia over a 10-year period. METHODS: Fetal blood samples (n= 30) taken before and after intrauterine transfusion were investigated. No cases were excluded, and there was no loss to follow up. MAIN OUTCOME MEASURES: Parameters recorded were gestational age, experienced fetal movements, gravidity and parity, severity of fetal hydrops, severity of fetal anaemia and thrombocytopenia and megakaryocyte and reticulocyte counts. Survival and procedure-associated complications were documented. Quantitative B19 viral load measurements were performed on all fetal samples. RESULTS: Forty-six percent of all hydropic fetuses showed severe thrombocytopenia. No antenatal intracerebral haemorrhage or procedure-associated bleeding occurred. Overall, survival was 77%. Platelet counts increased following platelet transfusion and decreased significantly following red blood cell transfusion alone. No correlation was found between fetal viral loads and platelet counts. CONCLUSION: Thrombocytopenia was frequently encountered in fetal B19V infection, but fetal bleeding complications were not noted. Absence of a direct relationship between fetal B19 viral load and platelet counts suggests a temporal dissociation between these findings. Dilutional thrombocytopenia is frequently seen in the fetus following red blood cell transfusion alone. The clinical significance of this phenomenon is unclear. The risk of fluid overload by fetal platelet transfusion in a severely hydropic fetus should be weighed against the low incidence of fetal bleeding complications.


Assuntos
Anemia/complicações , Hidropisia Fetal/virologia , Infecções por Parvoviridae/complicações , Parvovirus B19 Humano , Trombocitopenia/virologia , Adulto , Plaquetas/virologia , Transfusão de Sangue Intrauterina/métodos , Feminino , Sangue Fetal/virologia , Hemoglobinas/análise , Humanos , Contagem de Leucócitos , Transfusão de Plaquetas/métodos , Gravidez , Estudos Prospectivos , Estudos Retrospectivos , Trombocitopenia/terapia , Carga Viral
12.
Ned Tijdschr Geneeskd ; 152(21): 1185-90, 2008 May 24.
Artigo em Holandês | MEDLINE | ID: mdl-18578441

RESUMO

Four pregnant women, aged 29, 32, 36 and 36 years, respectively, were diagnosed with Human parvovirus B19 (B19V) infection. Only the first woman had exanthema and fever. In the first three cases, the source of infection appeared to be another child; two of these children were infected during a school outbreak. All four foetuses were infected, but the first foetus was asymptomatic and healthy at birth. The second foetus had anaemia and increased blood flow in the middle cerebral artery; it received an intrauterine transfusion and was healthy at birth. The third foetus was almost immobile and had cardiomegaly and hydrops fetalis; it was dead upon induced birth. In the fourth case, pregnancy was uneventful until two days before parturition, when the mother reported a decrease in foetal movement. The infant was born and developed respiratory insufficiency after 8 hours. Imaging revealed multiple bilateral lesions in frontal, occipital and parietal white matter consistent with infarction. The infant died after 5 days. Infection with B19V is associated with a wide range of clinical presentations and outcomes. Effects may range from an uncomplicated pregnancy to severe hydrops fetalis or intrauterine foetal death. Maternal symptoms may be aspecific, which complicates early diagnosis. When maternal B19V infection is suspected, immediate investigation for recent B19V infection should be performed. Quantitative B19 viral load measurements may provide insight into the stage of infection and may guide foetal monitoring. Referral to a foetal therapy unit is essential for hydrops fetalis or severe foetal anaemia. Intrauterine transfusion with erythrocytes significantly improves foetal outcome. Despite a successful transfusion procedure, long-term neurodevelopment may be affected, and developmental follow up is advised.


Assuntos
Morte Fetal , Infecções por Parvoviridae/diagnóstico , Parvovirus B19 Humano , Complicações Infecciosas na Gravidez/diagnóstico , Resultado da Gravidez , Adulto , Feminino , Humanos , Hidropisia Fetal/virologia , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Infecções por Parvoviridae/terapia , Infecções por Parvoviridae/transmissão , Gravidez , Complicações Infecciosas na Gravidez/terapia , Diagnóstico Pré-Natal
13.
Bone Marrow Transplant ; 40(2): 137-43, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17530007

RESUMO

Reports on infectious complications following reduced intensity conditioning (RIC) before allogeneic stem cell transplantation (allo-SCT) are equivocal. This prospective follow-up study compared the impact of cytomegalovirus (CMV) infections following RIC with fludarabine, ATG and busulphan or conventional myeloablative conditioning (MAC). Forty-eight RIC and 59 MAC patients were enrolled. The occurrence and severity of CMV infections within 100 days following allo-SCT were assessed, using plasma CMV DNA load kinetics. CMV DNAemia was observed in 21 RIC (60%) and in 19 MAC (44%) patients at risk for CMV. The mean CMV DNAemia free survival time was comparable following RIC and MAC: 70 days (95% (confidence interval) CI: 59-80 days) and 77 days (95% CI: 68-86 days), respectively (P=0.24). Parameters indicative for the level of CMV reactivation, including the area under the curve of CMV DNA load over time as well as the onset, the peak values and duration of CMV infection episodes, the numbers and duration of CMV treatment episodes and recurrent infections, were not different in both groups. During follow-up, none of the patients developed CMV disease. RIC with fludarabine, ATG and busulphan demonstrated safety comparable to conventional MAC with regard to frequency and severity of CMV infections within 100 days following T cell-depleted allo-SCT.


Assuntos
Infecções por Citomegalovirus/etiologia , Transplante de Células-Tronco/efeitos adversos , Condicionamento Pré-Transplante/efeitos adversos , Adulto , Idoso , Infecções por Citomegalovirus/virologia , DNA Viral/sangue , Feminino , Seguimentos , Neoplasias Hematológicas/terapia , Humanos , Depleção Linfocítica/efeitos adversos , Masculino , Pessoa de Meia-Idade , Neoplasias/terapia , Estudos Prospectivos , Recidiva , Linfócitos T/imunologia , Condicionamento Pré-Transplante/métodos , Transplante Homólogo
14.
Bone Marrow Transplant ; 38(1): 41-6, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16715108

RESUMO

Detection of Varicella-Zoster virus (VZV) DNA in plasma can facilitate the early recognition of complicated VZV-infection in immunocompromised hosts. The correlation of VZV-DNA in plasma with clinical presentations of VZV-infection and subsequent aciclovir treatment in allogeneic stem cell transplant (allo-SCT) recipients was studied. In 81 consecutive VZV-IgG positive allo-SCT recipients, VZV-DNA was measured at regular time points (1, 2 and 4 months) following allo-SCT and patient records were screened for VZV-related symptoms and aciclovir treatment. Subsequently, possible VZV-cases were studied in detail for the course of VZV-DNA and treatment effects. During the initial screening, VZV-DNA was detectable in seven patients. The survey of VZV-related symptoms revealed five additional possible VZV-cases. In cases where suitable plasma samples were available (10 out of 12), VZV-DNA was present almost simultaneously with the first clinical manifestations. No evidence of a preceding phase detectable by VZV-DNA only could be observed. Treatment with aciclovir was associated with a prompt reduction of VZV-DNA load. Detection of VZV-DNA in plasma in allo-SCT recipients accurately reflected the clinical presentation of VZV-infection and treatment with aciclovir. VZV-DNA detection in plasma of allo-SCT recipients appears clinically relevant as this may support early recognition and therapeutic management of VZV-infections following allo-SCT.


Assuntos
DNA Viral/sangue , Herpes Zoster/diagnóstico , Herpesvirus Humano 3/genética , Transplante de Células-Tronco/efeitos adversos , Aciclovir/uso terapêutico , Adulto , Idoso , Anticorpos Antivirais/sangue , Antivirais/uso terapêutico , Estudos de Coortes , Feminino , Herpes Zoster/sangue , Herpes Zoster/tratamento farmacológico , Herpesvirus Humano 3/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Fatores de Tempo , Transplante Homólogo , Resultado do Tratamento , Viremia/sangue , Viremia/diagnóstico
15.
Bone Marrow Transplant ; 37(7): 693-8, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16501590

RESUMO

The efficacy and safety of oral valganciclovir was compared to ganciclovir i.v. in pre-emptive treatment of cytomegalovirus (CMV) in T-cell-depleted allogeneic stem cell transplant (allo-SCT) recipients. A therapeutic guideline was developed to allow the safe application of valganciclovir in allo-SCT recipients requiring CMV therapy. In total, 107 consecutive transplant recipients were evaluated. Cytomegalovirus DNA load in plasma was monitored longitudinally; details on antiviral therapy and treatment responses were analyzed retrospectively. Fifty-seven CMV treatment episodes were recorded in 34 patients: 20 with valganciclovir (900 mg twice-daily) and 37 with ganciclovir (5 mg/kg twice-daily). Median CMV DNA load reduction was 0.079 and 0.069 log10 copies/ml/day in the ganciclovir and valganciclovir group, respectively. Good response on CMV DNA load (reduction below 3.0 log10 copies/ml) was observed in 75.7% of ganciclovir and 80.0% of valganciclovir treatment episodes. Severe adverse effects were not observed and CMV-related disease did not occur. However, the percentage of patients receiving erythrocyte transfusion was higher in the group of patients receiving ganciclovir as compared to valganciclovir (41 versus 20%, P=0.116). In conclusion, pre-emptive treatment with valganciclovir and ganciclovir, led to similar reduction of CMV DNA load. Oral valganciclovir is an attractive and safe alternative for pre-emptive CMV treatment in T-cell-depleted allo-SCT recipients.


Assuntos
Infecções por Citomegalovirus/prevenção & controle , DNA Viral/sangue , Ganciclovir/análogos & derivados , Ganciclovir/administração & dosagem , Transplante de Células-Tronco , Carga Viral , Administração Oral , Adulto , Antivirais/administração & dosagem , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Injeções Intravenosas , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Transplante de Células-Tronco/efeitos adversos , Transplante de Células-Tronco/métodos , Condicionamento Pré-Transplante , Transplante Homólogo , Resultado do Tratamento , Valganciclovir
16.
J Clin Pathol ; 59(5): 537-41, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16489178

RESUMO

OBJECTIVE: To evaluate the role of quantitative measurement of Epstein-Barr virus (EBV) DNA in the clinical management of nasopharyngeal carcinoma (NPC) in a low tumour risk area (western Europe). METHODS: 22 consecutive Dutch NPC patients (11 europid) were studied. EBV DNA load in pretreatment and post-treatment plasma samples was determined. Three patients were also sampled at frequent intervals during treatment. RNA in situ hybridisation for the detection of EBV encoded RNAs (EBERs) was carried out on tumour biopsies of all cases. RESULTS: All patients with EBER positive NPC (20/22) showed a positive EBV DNA load in plasma at the time of diagnosis (median EBV DNA level, 4.1 log(10) copies/ml). Patients with EBER negative NPC had no detectable EBV DNA in plasma. After treatment, complete remission was achieved in all cases and concurrently EBV DNA in plasma became undetectable in all patients. In the three longitudinally evaluated cases, EBV DNA load gradually declined towards undetectable levels within three weeks after start of treatment. Two patients developed a distant metastasis with concomitant increases in EBV viral load. In addition, one EBER positive patient developed an EBER negative metastasis in the neck during follow up and in this case EBV DNA load remained undetectable at the time of recurrence. CONCLUSIONS: Plasma EBV DNA load measurement appears to be useful in a low tumour risk area. However, development of local recurrences may not always coincide with raised levels of EBV DNA.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma/virologia , DNA Viral/sangue , Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/virologia , Adulto , Idoso , Biomarcadores Tumorais/análise , Carcinoma/terapia , DNA Viral/análise , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/terapia , Recidiva Local de Neoplasia/virologia , Reação em Cadeia da Polimerase/métodos , Risco , Sensibilidade e Especificidade , Carga Viral
17.
J Clin Virol ; 84: 19-23, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27664778

RESUMO

BACKGROUND: Parvovirus B19 (B19V) DNA can be detected in blood over a long period after acute infection. Several reports associate the presence of B19V DNA with disease, irrespective of timing of the initial B19V infection. OBJECTIVES: This study aims to analyze the properties of B19V DNA in blood, differentiating between bare, non-infectious strands of DNA and B19V DNA in viable virions. STUDY DESIGN: Ten blood donors with asymptomatic acute B19V infection were followed and sampled up to 22 months after infection. The samples were treated with and without an endonuclease and tested for B19V DNA, to distinguish between DNA in virions and naked DNA. RESULTS: In the acute phase of infection, high levels of B19V DNA were detected, concurrent with B19V IgM antibodies. B19V DNA apparently was encapsidated, as indicated by resistance to endonuclease degradation. Subsequently, B19V DNA remained detectable for more than one year in all donors at low levels (<105 IU/mL). Approximately 150days after infection B19V DNA became degradable by an endonuclease, indicating that this concerned naked DNA. In some donors a second endonuclease-resistant peak occurred. DISCUSSION: Detection of B19V DNA in blood by PCR does not necessarily imply that B19V replication takes place and that infectious B19V virions are present. We propose that remnant B19V DNA strands can be released from tissues without active replication. This finding urges to reconsider an assumed role of B19V infection mainly based on B19V DNA detection in blood, a much debated subject in clinical syndromes such as myocarditis and arthritis.


Assuntos
Doadores de Sangue , DNA Viral/sangue , Infecções por Parvoviridae/diagnóstico , Parvovirus B19 Humano/genética , Parvovirus B19 Humano/isolamento & purificação , Anticorpos Antivirais/sangue , Artrite/diagnóstico , Artrite/virologia , DNA Viral/genética , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Miocardite/diagnóstico , Miocardite/virologia , Infecções por Parvoviridae/virologia , Parvovirus B19 Humano/imunologia , Reação em Cadeia da Polimerase , Fatores de Tempo , Replicação Viral
18.
Bone Marrow Transplant ; 36(1): 39-50, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15908981

RESUMO

Adenovirus (HAdV) infections are a frequent cause of morbidity and mortality after allogeneic human stem cell transplantation (HSCT). We report a retrospective single-centre study on 328 consecutive paediatric recipients of an allogeneic HSCT. During the first 6 months after HSCT, HAdV infection occurred in 37 children (cumulative incidence 12%). The highest incidence was found in young children up to 5 years of age, transplanted after 1994, with >2 log T-cell depletion of a graft of another than an HLA-genotypically identical related donor (actuarial frequency at 6 months 84%). Persistence of HAdV and spreading of the virus over multiple sites showed a trend towards the development of HAdV disease or death, but did not reach significance. Recovery of immunity after HSCT, that is, serum concentrations of IgM and peripheral blood counts of T cells and subsets, was delayed in children with an HAdV infection compared with noninfected children. In seven out of seven patients with HAdV DNA in serum and decreasing lymphocyte counts, the infection had a fatal course. Manipulation of cellular immunity either by tapering of immunosuppression, infusion of donor lymphocytes or immunotherapy using HAdV-specific T cells should be considered in graft recipients at risk for a severe HAdV infection.


Assuntos
Infecções por Adenovirus Humanos/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hospedeiro Imunocomprometido , Infecções por Adenovirus Humanos/imunologia , Infecções por Adenovirus Humanos/mortalidade , Adolescente , Fatores Etários , Criança , Pré-Escolar , DNA Viral/sangue , Feminino , Doenças Hematológicas/complicações , Doenças Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/mortalidade , Histocompatibilidade , Humanos , Imunidade Celular , Incidência , Lactente , Contagem de Linfócitos , Depleção Linfocítica , Masculino , Estudos Retrospectivos , Fatores de Risco , Transplante Homólogo
19.
Bone Marrow Transplant ; 35 Suppl 1: S73-6, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15812536

RESUMO

Human adenoviruses (HAdV) are a frequent cause of potentially fatal infections in patients after allogeneic stem cell transplantation, especially in children. Monitoring of serum/plasma by real-time quantitative PCR is a sensitive tool for the recognition of patients at risk of a potentially fatal infection and for the evaluation of the efficacy of treatment. Data from a retrospective study and from a prospective study demonstrate that recovery of immunity after transplantation is essential for the elimination of HAdV infection. The feasibility of several approaches for the manipulation of immunity in the immunocompromised host to prevent a fatal course of the infection is discussed.


Assuntos
Infecções por Adenovirus Humanos , Transplante de Células-Tronco , Infecções por Adenovirus Humanos/sangue , Infecções por Adenovirus Humanos/diagnóstico , Infecções por Adenovirus Humanos/tratamento farmacológico , Criança , Pré-Escolar , DNA Viral/sangue , Feminino , Humanos , Masculino , Estudos Retrospectivos , Transplante Homólogo
20.
J Clin Virol ; 63: 53-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25600606

RESUMO

BACKGROUND: Cytomegalovirus (CMV) infections occur worldwide and are usually asymptomatic in healthy individuals. In fetuses and immunocompromised persons, they can cause severe disease and disabilities. OBJECTIVE: To determine the CMV seroprevalence and risk factors for CMV infection in the Netherlands. STUDY DESIGN: In a cross-sectional population-based study (PIENTER-2, 2006-2007), sera and questionnaire data were collected from 6386 individuals. Sera were tested for CMV-specific IgG antibodies using enzyme-linked immunosorbent assay (ELISA). RESULTS: The CMV seroprevalence in the general population (6 months-79 years) was 45.6%. Age and country of origin were the most prominent independent risk factors. The seroprevalence was significantly lower in native Dutch and Western individuals (41.5%) than in non-Western individuals (76.7%). Multivariable logistic regression analysis showed that age, lower educational level, first-generation migrancy, and among native Dutch/Western individuals, female gender and having contact with young children, were independently associated with CMV seropositivity. The geometric mean concentrations of antibodies increased with age and were higher in women than in men. CONCLUSION: CMV seroprevalence in the Netherlands is relatively low compared to other countries. This is in line with our finding of a higher seroprevalence among migrants compared to the native population. The higher seroprevalence in women and individuals who have contact with young children is especially important for women of reproductive age. Preventing CMV infection in these women, through counseling on hygiene or possible future vaccination, may lead to a decrease of congenital CMV infections.


Assuntos
Controle de Doenças Transmissíveis/métodos , Infecções por Citomegalovirus/epidemiologia , Adolescente , Adulto , Idoso , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Estudos Transversais , Infecções por Citomegalovirus/prevenção & controle , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Lactente , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Fatores de Risco , Estudos Soroepidemiológicos , Inquéritos e Questionários , Adulto Jovem
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