Neuromyelitis Optica Spectrum Disorders in Black African: Experience of Togo (2015-2020)

Abstract

Introduction Neuromyelitis optica spectrum disorders (NMOSD) would disproportionately affect blacks within mixed populations. However, they are rarely reported in black African. The objective of this work was to report the experience of Togo, a West African country in terms of NMOSD. Methods This is a series of six cases diagnosed between 2015 and 2020 in the only three neurology departments in Togo. The diagnosis of NMOSD was made according to the criteria of the International Panel for NMO Diagnosis (2015) and the patients had a minimum clinical follow-up of 6 months after the diagnosis. The search for anti-aquaporin 4 (AQP4) antibodies was performed by immunofluorescence on transfected cells. Results The mean age was 25.33 years and the sex ratio female/male was 5/1. The average time between the first attack and the diagnosis was 122.83 days. Clinically, there was isolated medullary involvement (2/6), simultaneous opticomedullary involvement (3/6), and area postrema syndrome (1/6). Five patients were anti-AQP4 positive. All six patients had extensive longitudinal myelitis. At 6 months of follow-up, there was one case of death and one case of blindness. Conclusion The rarity of NMOSD cases in Togo could be linked to an underestimation. To better characterize the NMOSDs of the black African population, multicenter and multidisciplinary studies are necessary.