-Background: Dengue infection may cause neurological manifestations such as encephalitis, myelitis, mononeuropathies, acute disseminated encephalomyelitis, and Guillain Barré syndrome (GBS). In endemic regions, the infection course can be oligosymptomatic making difficult the diagnosis of the neurological picture associated with dengue infection. Objective: To report dengue infection and GBS association, even in oligosymptomatic cases of this infection. Method: During the dengue epidemic in Rio de Janeiro city we looked for GBS cases, testing IgM antibodies for dengue and dengue polymerase chain reaction (PCR) in the cerebrospinal fluid (CSF) and serum. Results: We report seven cases (46.6%), presenting dengue positive IgM in serum but with poor or without clinical symptoms of the previous infection. Two of them had also positive IgM antibodies in CSF. Conclusion: These data show that search for dengue infection should be a routine in GBS cases living in endemic areas.Key WoRDS: dengue, polyradiculoneuritis, radiculoneuropathy, CSF, Guillain Barré syndrome. Dengue oligossintomática: causa potencial de síndrome de Guillain BarréResumo -Introdução: o vírus da dengue pode determinar várias manifestações neurológicas como: encefalite, mielite, mononeuropatias, encefalomielite disseminada aguda e a síndrome de Guillain Barré (SGB). em regiões endêmicas a infecção pode ser oligosintomática dificultando o diagnóstico neurológico associado a infecção por dengue. Objetivo: Relatar a associação entre SGB e o vírus da dengue, principalmente em formas oligosintomáticas da infecção. Método: Durante epidemia pelo vírus da dengue na cidade do Rio de Janeiro, casos de SGB foram selecionados e tiveram suas amostras de soro e líquido cefalorraqueano (LCR) testadas para anticorpos dengue IgM e PCR para dengue. Resultados: Descrevemos sete casos (46,6%) com diagnóstico de SGB, apresentando IgM positiva para dengue no soro, porém com poucos ou nenhum sintoma infeccioso prévio. Dois pacientes também apresentavam IgM positiva no LCR. Conclusão: estes dados sugerem que a pesquisa para o vírus da dengue deve ser realizada em todos os casos de SGB em áreas endêmicas.PALAvRAS-ChAve: dengue, polirradiculoneurite, radiculoneuropatia, líquido cefalorraqueano e síndrome de

Objectives: It was the aim of this study to evaluate if the quantitative intrathecal immunoglobulin G (IgG) synthesis correlates with the brain atrophy and the total lesion volume (TLV) in brain magnetic resonance imaging (MRI) of multiple sclerosis (MS) patients. Methods: A total of 50 patients with relapsing-remitting MS were included in this study. MRIs were performed and cerebrospinal fluid samples were collected during the diagnostic determination when patients were in remission without treatment. Results: At study baseline, IgG index values were elevated in 36 patients (72%), and oligoclonal IgG bands were positive in 42 of 50 patients (84%). Brain MRI was abnormal in 94% of patients, and, compared with healthy controls, brain atrophy was observed in MS patients. A positive correlation among IgG index, cerebrospinal fluid leukocyte count and TLV was observed; the Expanded Disability Status Scale correlated positively with TLV and the number of lesions, although a significant relationship between disability and brain atrophy was not demonstrated. Conclusions: Although new parameters will be necessary in longitudinal studies to characterize the axonal injury in various stages of the disease, the data suggest that the high intrathecal IgG synthesis may predict a greater brain lesion burden.

-Cytokines and intrathecal IgG synthesis were determined in the cerebrospinal fluid (CSF) and sera to evaluate inflammatory activity in multiple sclerosis (MS) patients during clinical remission. Although the disease was stable, there had been a significant increase of pro i n f l a m m a t o ry cytokines such as TNFα and IFNγ in the CSF and serum, with no significant changes of IL12 and IL10 production. The changes in t h e cytokine production patterns were associated with an increase of leukocytes in the CSF, as well as the pre sence of oligoclonal bands suggesting intrathecal IgG synthesis. These results suggest that even when the disease is clinically silent, one can observe inflammatory activity in these MS patients.KEY WORDS: multiple sclerosis; cerebrospinal fluid; cytokines; intrathecal IgG synthesis.Citocinas e síntese intratecal de IgG em pacientes com esclerose múltipla durante remissão clínica RESUMO -Os níveis de citocinas e síntese intratecal de IgG foram dosados no líquido cefalorr a q u i d i a n o (LCR) e soro, com o objetivo de avaliar a atividade inflamatória em pacientes com esclerose múltipla durante remissão clínica. Foram detectados níveis elevados de citocinas pró-inflamatórias (TNFα e IFNγ) no LCR e s o ro, sem alterações significativas na produção de IL12 e IL10. O perfil de produção das citocinas pró-inflamatórias estava associado ao aumento de leucócitos no LCR, assim como a presença de bandas oligoclonais IgG sugerindo síntese intratecal de IgG. Estes resultados sugerem que mesmo quando a doença está clinicamente silenciosa, a atividade inflamatória está presente nestes pacientes. PALAVRAS-CHAVE: esclerose múltipla, líquido cefalorraquidiano, citocinas, IgG síntese intratecal.

Objective: The pathological hallmarks of multiple sclerosis (MS) lesions are inflammation, demyelination, axon loss and gliosis. The aim of this study was to verify the relation of brain lesion load and volume of the cerebral hemisphere determined by brain MRI with intrathecal antibody synthesis. Methods: A longitudinal study of 54 Brazilian patients with the relapsing-remitting form of MS was undertaken after an average of 6.3 ± 2.7 years of treatment. MRI scans were performed, and cerebrospinal fluid samples were collected both during the diagnostic process and after treatment with β-interferon or glatiramer acetate. Results: A positive correlation between the IgG index and total lesion volume was identified. Intrathecal IgG against Epstein-Barr virus (EBV) was observed in 21 patients. The number of contrast-enhanced lesions observed in these patients was correlated with intrathecal IgM synthesis. Brain atrophy was observed early in the disease, with the number of relapses inversely correlated with brain volume. Conclusion: The high intrathecal IgG synthesis observed in these relapsing-remitting MS patients is associated with the brain lesion burden and the presence of antibodies to EBV, whereas intrathecal IgM synthesis is associated with the activity of the disease, as revealed by MRI.