RESUMO
Dengue virus (DENV) infects approximately 390 million persons every year in more than 100 countries. Reports of neurological complications are more frequently. The objective of this narrative review is to bring up the advances in the dengue neuropathogenesis. DENV can access the nervous system through blood-brain barrier disturbance mediated by cytokine. The blood-cerebrospinal fluid (CSF) barrier seems to be also involved, considering the presence of the virus in the CSF of patients with neurological manifestations. As for neurotropism, several studies showed the presence of RNA and viral antigens in brain tissue and CSF in humans. In murine model, different virus mutations were associated to neurovirulence. Despite the advances in the dengue neuropathogenesis, it is still necessary to determine a more appropriate animal model and increase the number of cases of autopsy. The detection of neurovirulence markers may contribute to establish a prognosis, the disease control and vaccine development.
O vírus da dengue (DENV) infecta anualmente cerca de 390 milhões de indivíduos em mais de 100 países. Complicações neurológicas estão se tornando frequentes. O objetivo desta revisão narrativa é abordar os avanços sobre neuropatogênese na dengue. O DENV invade o sistema nervoso central através do distúrbio da barreira hemato-encefálica, mediado por citocina. A barreira hemato-liquórica (LCR) parece também estar envolvida, considerando a presença do vírus no LCR. Estudos demonstraram RNA e antígenos virais no tecido cerebral e LCR de indivíduos infectados pelo DENV, confirmando o neurotropismo viral. Em modelo murino, diferentes mutações virais foram associadas a neurovirulência. Apesar dos avanços no conhecimento da neuropatogênese da dengue, ainda são necessários a determinação de um modelo animal mais adequado e aumento do número de casos de autopsia. A determinação de marcadores de neurovirulência pode contribuir para o estabelecimento de prognóstico, controle da doença e no desenvolvimento de vacina.
Assuntos
Animais , Humanos , Doenças do Sistema Nervoso Central/virologia , Vírus da Dengue , Dengue/complicações , Sistema Nervoso Central/virologia , Modelos Animais de Doenças , Vírus da Dengue/genética , Dengue/virologia , Ilustração Médica , MutaçãoRESUMO
The purpose of this study was to use the polymerase chain reaction [PCR] technique to detect herpes simplex virus genome in cerebrospinal fluid [CSF], together with enzyme immunoassay and antigen immunoblotting [AIB] to detect antibodies against herpes simplex virus, in 41 patients with encephalitis and similar infectious diseases of the central nervous system. None of the patients had the diagnosis of herpes simplex encephalitis. Cerebrospinal fluid and matched serum specimens were obtained within the first week of clinical symptoms. Oligoclonal IgG bands were found by isoelectric focusing in the cerebrospinal fluid of 20/41 patients of whom 9 had local synthesis and 11 had a systemic immune response. Antibody specific to herpes simplex virus was found by enzyme-linked immunosorbent assay [ELISA] in 10/33 patients tested. Herpes simplex virus-specific antibodies were found in the cerebrospinal fluid by antigen immunoblotting in 5/31 patients investigated, but these were of low affinity. There was no correlation between findings on ELISA and either the clinical diagnosis, the presence of oligoclonal IgG by isoelectric focusing, or the detection of specific antibodies by antigen immunoblotting. Careful interpretation of specific antibodies is necessary for they may result from non-specific activation by an unrelated agent. Polymerase chain reaction for herpes simplex virus deoxyribonucleic acid [DNA] may be used to help in the diagnosis of early cases of HSE and should also be considered in cases presenting with atypical clinical features and inconclusive results from laboratory tests
Assuntos
Humanos , Masculino , Feminino , Simplexvirus/isolamento & purificação , Doenças do Sistema Nervoso Central/virologia , Simplexvirus/imunologia , Anticorpos Antivirais , Reação em Cadeia da Polimerase , Immunoblotting , Técnicas ImunoenzimáticasRESUMO
As meningoencefalites por vírus determinam um padrao de hipercelularidade liquórica tipo linfomonocitário e seus agentes etiológicos sao pouco conhecidos no Brasil. Aspectos da patogenia das viroses que acometem o sistema nervoso central sao analisados desde o momento da infecçao. Os mecanismos de defesa antiviral do hospedeiro, a chegada dos vírus ao sistema nervoso central, suas distintas formas de invasao do tecido nervoso, bem como o acometimento deste tecido e a imunidade a nível local, sao abordados neste trabalho de revisao.