Influence of natalizumab on resting-state connectivity in patients with multiple sclerosis.

Background: Changes in brain connectivity occur in patients with multiple sclerosis (MS), even in patients under disease-modifying therapies. Using magnetic resonance imaging (MRI) to asses patients treated with disease-modifying therapies, such as natalizumab, can elucidate the mechanisms involved in clinical deterioration in MS. Objectives: To evaluate differences in resting-state functional connectivity among MS patients treated with natalizumab, MS patients not treated with natalizumab, and controls. Design: Single-center retrospective cross-sectional study. Methods: Twenty-three MS patients being treated with natalizumab were retrospectively compared with 23 MS patients who were naïve for natalizumab, and were using first-line medications (interferon-ß and/or glatiramer acetate), and 17 gender- and age-matched control subjects. The MS patient groups were also matched for time since diagnosis and hyperintense lesion volume on FLAIR. All participants underwent brain MRI using a 3 Tesla scanner. Independent component analysis and dual regression were used to identify resting-state functional connectivity using the FMRIB Software Library. Results: In comparison to controls, the MS patients treated with natalizumab presented decreased connectivity in the left orbitofrontal cortex, in the anterior cingulate and orbitofrontal cortex network. The patients not treated with natalizumab presented increased connectivity in the secondary visual, sensorimotor, and ventral attention networks in comparison to controls.Compared to patients treated with natalizumab, the patients not using natalizumab presented increased connectivity in the left Heschl's gyrus and in the right superior frontal gyrus in the ventral attention network. Conclusion: Differences in brain connectivity between MS patients not treated with natalizumab, healthy controls, and patients treated with natalizumab may be secondary to suboptimal neuronal compensation due to prior less efficient treatments, or due to a compensation in response to maladaptive plasticity.

Clinical Characteristics of Patients With Neuromyelitis Optica Spectrum Disorders With Early Onset.

Neuromyelitis optica spectrum disorder is a severe and disabling disease that manifests with severe relapses of optic neuritis, longitudinally extensive myelitis, and/or brainstem syndromes. The disease is complex and, although onset typically occurs in middle age, children and adolescents may be affected. The present study adds to the literature through detailed clinical data from 36 Brazilian patients with neuromyelitis optica spectrum disorder starting before age 21. This was a retrospective assessment of medical records from 14 specialized units in Brazil. The results showed that the course of neuromyelitis optica spectrum disorder was worse in patients with disease onset before the age of 12 years. Gender and ethnic background did not influence disability accumulation. Over a median period of 8 years, 14% of the patients who presented the initial symptoms of neuromyelitis optica spectrum disorder before the age of 21 years died. In conclusion, the present study adds to the reports from other authors examining the severity of early-onset neuromyelitis optica spectrum disorder.

Clinical characteristics of 153 Brazilian patients with neuromyelitis optica spectrum disorder (NMOSD).

BACKGROUND: The 2015 criteria for diagnosing neuromyelitis optica spectrum disorder (NMOSD) have encouraged several groups across the world to report on their patients using these criteria. The disease typically manifests with severe relapses of optic neuritis, longitudinally extensive myelitis and/or brainstem syndromes, often leading to severe disability. Some patients are seropositive for antibodies against aquaporin-4 (AQP4), others are positive for anti-myelin oligodendrocyte glycoprotein (MOG), while a few are negative for both biomarkers. The disease is complex, and only now are specific therapeutic clinical trials being carried out. The present study adds to the literature through detailed clinical data from 153 medical records of Brazilian patients. METHODS: Retrospective assessment of medical records from nine specialized units in Brazil. RESULTS: NMOSD was more prevalent in females (4.1:1), who had significantly fewer relapses than males (p = 0.007) but presented similar levels of disability over time. African ancestry was associated with higher levels of disability throughout the disease course (p < 0.001), although the number of relapses was similar to that observed in white patients. Concomitant autoimmune diseases were relatively rare in this population (6.5%). Positivity for anti-AQP4 antibodies was identified in 62% of the patients tested, while 3% presented anti-MOG antibodies. Anti-AQP4 antibodies were not associated to worse disease course. The last medical record showed that six patients had died and 13 were wheelchair-bound. Seventy percent of the patients did not respond to first-line therapy (azathioprine and/or corticosteroids), and five patients continued to relapse even after four different courses of treatment. CONCLUSION: The present study adds to the reports from other countries presenting original data on Brazilian patients diagnosed with NMOSD according to the 2015 criteria.

Anti-Musk Positive Myasthenia Gravis and Three Semiological Cardinal Signs.

Myasthenia gravis (MG) is a relatively uncommon disorder with an annual incidence of approximately 7 to 9 new cases per million. The prevalence is about 70 to 165 per million. The prevalence of the disease has been increasing over the past five decades. This is thought to be due to better recognition of the condition, aging of the population, and the longer life span of affected patients. MG causes weakness, predominantly in bulbar, facial, and extra-ocular muscles, often fluctuating over minutes to weeks, in the absence of wasting, sensory loss, or reflex changes. The picture of fluctuating, asymmetric external ophthalmoplegia with ptosis and weak eye closure is virtually diagnostic of myasthenia. We report an atypical MG case with three semiological cardinal signs.