Clinical course of neuromyelitis optica spectrum disorder in a moroccan cohort

Background: Neuromyelitis optica spectrum disorder (NMOSD) was suggested to be more frequent and have specific features among populations from Africa or North Africa. However, we could not find any large study about NMOSD in an African population in the medical literature. Objectives: To describe the characteristics of NMOSD in a Moroccan monocenter population. Patients and methods: A retrospective study was conducted. Patients from January 1999 to December 2015 fulfilling the 2015 International Consensus Criteria for NMOSD were included. Results: Sixty four patients fulfilled the criteria. Mean age at onset was 35.7 +/- 10.7 years, and the sex ratio was 1/3.57. First clinical event was represented by optic neuritis (38.1%), followed by myelitis (27.0%) and a Devic's syndrome (17.2%). Mean annualized relapse rate was 1.07 +/- 1.23 and mean EDSS at last visit was 5.1 +/- 2.8. Aquaporine 4 antibodies were positive in 47.1%. Brain lesions were found in 71.2%. Most patients (76.6%) received disease-modifying therapy, mainly cyclophosphamide (86.0%) and 49% remained relapse-free after treatment initiation Conclusion: Data from our study suggest more similarities between North African NMOSD patients and non Caucasian populations. More studies are needed to assess other pathological patterns and compare disease course to other populations.