Fabíola Rachid Malfetano

The Role of Demyelination in Neuromyelitis Optica Damage: Diffusion-Tensor MR Imaging Study

PURPOSE To test the hypothesis that white matter damage in neuromyelitis optica (NMO) is more extensive than previously described and likely includes involvement of normal-appearing white matter and to explore by using diffusion-tensor (DT) imaging whether white matter lesions are not only related to wallerian degeneration but are also caused by demyelination. MATERIALS AND METHODS Seventeen patients with NMO (mean age, 45 years; 14 women) were compared with 17 sex- and age-matched control subjects. The institutional review board approved the study, and all subjects gave written informed consent. In addition to conventional magnetic resonance imaging sequences, DT imaging was performed along 30 noncollinear directions by using a 1.5-T imager. For tract-based spatial statistics (TBSS) analysis, the white matter skeleton was created, and a permutation-based inference with 5000 permutations with a threshold of P less than .05 to enable the identification of abnormalities in fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD) was used. Partial correlation was applied to identify whether the number of clinical relapses and disease duration were correlated with all TBSS parameters. RESULTS TBSS showed multiple areas with significant FA decrease in patients with NMO, mainly located in the corona radiata, uncinate fasciculus, corpus callosum, optic radiation, internal and external capsules, and cerebral peduncles. The mean FA, RD, and AD in the abnormal voxels located on the corpus callosum were, respectively, 0.69 ± 0.03 (standard deviation), 0.39 × 10(23) mm(2)/sec ± 0.04, and 1.53 × 10(23) mm(2)/sec ± 0.04 in patients with NMO compared with 0.75 ± 0.02, 0.33 × 10(23) mm(2)/sec ± 0.03, and 1.57 × 10(23) mm(2)/sec ± 0.04 in control subjects (P < .0001, P < .0001, and P = .007, respectively). There was a highly significant inverse correlation between FA and RD (r = 20.976, P < .0001). CONCLUSION The use of TBSS allowed the identification of extensive white matter damage in patients with NMO. Multiple white matter tracts were involved, including the pyramidal tract, optic radiation, and corpus callosum, likely related to both demyelination and wallerian degeneration.

Acute disseminated encephalomyelitis: clinical features, HLA DRB1*1501, HLA DRB1*1503, HLA DQA1*0102, HLA DQB1*0602, and HLA DPA1*0301 allelic association study

We evaluated the frequency, demographic, clinical, disability evolution and genetic association of HLA DRB1*1501, DRB1*1503, DQA1*0102, DQB1*0602 and DPA1*0301 alleles in patients diagnosed as acute disseminated encephalomyelitis (ADEM) among a population of CNS demyelinating diseases. Fifteen patients (8.4%) of our series were diagnosed as ADEM. The mean age onset was 35.23 years (range 12 to 77), 53.3% were male and follow-up range was 8.5 to 16 years. Two cases (13.3%) had a preceding infection before neurological symptoms, one presented a parainfectious demyelinating, and one case had been submitted to hepatitis B vaccination four weeks before the clinical onset. The EDSS range was 3.0 to 9.5. Eight patients (53.3%) presented MRI with multiple large lesions. CSF was normal in 73.3%. The severe disability observed at EDSS onset improved in 86.66% patients. The genetic susceptibility for ADEM was significantly associated with the HLA DQB1*0602, DRB1*1501 and DRB1*1503 alleles (<0.05) in monophasic ADEM.

Brain MRI abnormalities in Brazilian patients with neuromyelitis optica.

Brain abnormalities in neuromyelitis optica (NMO) have been reported previously, but the pathophysiological mechanism and clinical relevance of these abnormalities are poorly understood. We assessed the prevalence and patterns of brain MRI abnormalities in a Brazilian cohort of patients with NMO. Conventional brain MRI and medical records from 24 Brazilian patients with NMO were retrospectively evaluated. Brain MRI were classified into four subgroups: normal, non-specific lesions, multiple sclerosis (MS)-like lesions, and typical lesions. Brain lesions were detected in 19 patients (79.2%). Fourteen patients (58.3%) had non-specific lesions, three (12.5%) had MS-like lesions, and two (8.3%) had typical lesions. Differences between these subgroups with respect to the Expanded Disability Status Scale (EDSS) scores (p=0.86) were not significant. This study demonstrates a high prevalence of brain abnormalities in Brazilian patients with NMO; however, we did not find a significant relationship between these abnormalities and EDSS scores.

Multiple sclerosis outcome and morbi-mortality of a Brazilian cohort patients

We studied the clinical and evolution characteristics of multiple sclerosis (MS) patients followed since the onset of HUCFF/UFRJ in 1978. The diagnosis of MS was based on Posers et al. and MC Donalds et al. criteria. From 188 patients, 122 were included. Eighty-five were females. The mean age onset was 32.2 years-old (range 6.0 to 61.0+/-10.3), mainly Caucasians (82/67%). The relapsing-remitting course (MSRR) was more frequent (106/86.8%). Monosymptomatic onset was significantly more frequent in Caucasians than in Afro-Brazilians (p<0.05). Seventeen patients had benign form of MS and these patients presented association with MSRR when compared with severe form (p=0.01). The mortality rate was 2.12% (4 patients died). This study was similar to other Brazilian series with regard to sex and age, and lack of correlation between EDSS and number of relapses; it confirmed south-southeast African-descendants gradient distribution and association between first mono-symptomatic relapses and Caucasian; we found lower frequency of benign forms.

Immune system markers of neuroinflammation in patients with clinical diagnose of neuromyelitis optica

Neuromyelitis optica (NMO) is an inflammatory, demyelinating disease of the central nervous system characterized by the association of a serious myelitis and unilateral or bilateral optic neuritis. The present study aimed to analyze the immunological parameters of NMO patients with diagnosis established based on Wingerchuck et al. (1999) criteria. Production of IgG and IgA antibodies to antigens of MBP, PLP 95-116, MOG 92-106, and the cytokines interleukin-4 (IL-4) and interferon-gamma (INF-gamma) were assessed by Elisa assay. The cohort was formed by 28 NMO patients and a matched healthy control group. NMO patients had significant high levels of IgG to MOG (p<0.0001), PLP (p=0.0002) and MBP (p<0.0001), and solely IgA to MBP (p<0.0001). INF-gamma (p=0.61) levels were similar to healthy controls. Increased production of IL-4 (p=0.0084) indicates an important role for this cytokine in the activation of Th2 regulatory cells and of the IgA producers B lymphocyte indicating activation of humoral immunity.

Natalizumab adverse events are rare in patients with multiple sclerosis

OBJECTIVE To assess the prevalence and the profile of adverse events (AE) of natalizumab in patients with multiple sclerosis (MS). METHODS Data collection from neurologists attending to patients with MS at specialized units in Brazil. RESULTS Data from 103 patients attending the infusion centers of 16 MS units in 9 Brazilian states were included in the study. The total number of infusions was 1,042. Seventy-nine patients (76.7%) did not present any AE. Twenty-four patients (23.3%) presented only mild AE. There were three major AE, including two deaths. These three occurrences, although not necessarily being drug-related, must be taken into consideration. CONCLUSION The profile of AEs for natalizumab shows that 97% of patients have none or only mild AE. However, still due to safety worries, the use of this medication should be restricted to MS units under the care of specialized neurologists.

Clinical response to interferon beta and glatiramer acetate in multiple sclerosis patients: a Brazilian cohort

INTRODUCTION Many patients with multiple sclerosis (MS) are currently receiving treatment with interferon beta (IFNb) and glatiramer acetate (GA). Identifying nonresponders patients is important to define therapy strategies. Several criteria for treatment response to IFNb and GA have been proposed. OBJECTIVE It was to investigate the response to treatment with IFNb-1a, IFNb-1b and GA among relapsing-remitting multiple sclerosis (RRMS) patients. METHODS We analyzed treatment response to IFNb and GA in ninety-one RRMS patients followed for at least one year. Clinical response was established by clinical criteria based on relapses, disability progression or both. RESULTS We observed a proportion of nonresponders, ranging from 3.3 to 42.9%, depending on the stringency of the criteria used. CONCLUSIONS Our sample of Brazilian patients with MS has similarities when compared to other studies and there was no statistically significant difference regarding age, gender, ethnicity or disease duration between responders and nonresponders.

The CIITA genetic polymorphism rs4774*C in combination with the HLA-DRB1*15:01 allele as a putative susceptibility factor to multiple sclerosis in Brazilian females

The objective of this study was to investigate the association between the HLA alleles at the DQA1, DQB1 and DRB1 loci, the CIITA genetic polymorphisms -168A/G and +1614G/C, and susceptibility to multiple sclerosis (MS) in a sample from Rio de Janeiro State, Brazil. Furthermore, we wished to determine whether any of these associations might be more significant in women compared with men. DNA samples from 52 relapsing-remitting MS (RRMS) patients and 126 healthy controls matched for sex and age were analyzed. We identified a significant HLA-DRB1*15:01-MS association that was female-specific (Odds Ratio (OR) = 4.78; p = 0.001). Furthermore, we observed that the +1614G/C mutation in combination with the HLA-DRB1*15:01 allele increased susceptibility to MS in females (OR = 4.55; p = 0.01). Together, these findings highlight the polygenic nature of MS.

Default-mode network and deep gray-matter analysis in neuromyelitis optica patients

OBJECTIVE The aim of our study was to detect functional changes in default-mode network of neuromyelitis optica (NMO) patients using resting-state functional magnetic resonance images and the evaluation of subcortical gray-matter structures volumes. MATERIALS AND METHODS NMO patients (n=28) and controls patients (n=19) were enrolled. We used the integrated registration and segmentation tool, part of FMRIBs Software Library (FSL) to segment subcortical structures including the thalamus, caudate nucleus, putamen, hippocampus and amygdalae. Resting-state functional magnetic resonance images were post-processed using the Multivariate Exploratory Linear Optimized Decomposition into Independent Components, also part of FSL. Average Z-values extracted from the default-mode network were compared between patients and controls using t-tests (P values <0.05 were considered statistically significant). RESULTS There were areas of increased synchronization in the default-mode network of patients compared to controls, notably in the precuneus and right hippocampus (corrected P<0.01). The frontal area had decreased synchronization in patients compared to controls (corrected P<0.01). There were no observed differences between patients and controls in subcortical volumes or average Z-values values for default-mode network. CONCLUSION The hyperactivity of certain default-mode network areas may reflect cortical compensation for subtle structural damage in NMO patients.