NMO IgG positive antibodies in NMO patients had a lower rate in the Caribbean area - where the population has a predominant African ancestry - than in Caucasian Europeans, suggesting the influence of a possible ethnic factor in the pathogenesis of the disease, but they confer a worse course with more attacks, more disability and MRI lesions.

We studied cranial magnetic resonance imaging (MRI) lesions in three women with acute attacks of recurrent longitudinally extensive transverse myelitis (r-LETM), recurrent-optic neuritis (r-ON) and r-LETM-CNS. Neuromyelitis Optica -immunoglobulin (IgG) antibody was positive in all cases. Brain MRI (1.5 Tesla) was performed according to protocol from consortium MS centre. We described the cranial lesions in brain MRI of acute relapses. These lesions were different from MS, most had an asymptomatic course which disappeared with time, protocol from consortium of MS centre criteria for brain MRI and seropositivity of NMO-IgG are useful tools for differentiate acute lesions of NMO/MS.

Neuromyelitis optica (NMO), an uncommon central nervous system (CNS) demyelinating disease, produces transverse myelitis and severe optic neuritis. IgG-NMO autoantibody, a specific immunoglobulin binding aquaporin-4 water channel protein, confirms that NMO is a different entity to multiple sclerosis. Parallel to cytokine down-regulations found in serum of relapsing-NMO (rNMO) patients, it has been reported that IgG-NMO may also confer a worse course of the disease in r-NMO Caribbean patients. In this study, we were interested in exploring the influence of IgG-NMO autoantibody on S100β levels and clinical parameters from serum of r-NMO patients. Serum samples from 24 rNMO patients and 10 controls were evaluated. The reduction of S100β observed in r-NMO patients was not significant compared to controls; and no differences were present regarding IgG-NMO immunoreactivity. At the same time, a significant correlation was also observed between IgG-NMO autoantibody serum detection and EDSS (Expanded Disability Status Scale) in rNMO. These results corroborate a differential regulation of IgG-NMO autoantibodies on the S100β glial marker and on the disability present in rNMO patients.