P057 - Remarkable response of seropositive neuromyelitis optica to rituximab therapy – First report from kingdom of Bahrain

Abstract

Background Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the central nervous system that causes severe optic neuritis and myelitis attacks. Humoral immunity seems to have a prominent role in the pathogenesis of the disease. Recently the nature and understanding of NMO have been revolutionized by two factors (1) the identification of both a NMO IgG as a sensitive and specific diagnostic marker and (2) the identification of both specific radiological and pathologic features of the disease. Also with the limited treatment options, recently positive results reported with the use of the anti-CD20 monoclonal antibody rituximab are promising. Objectives We present 2 cases, first to be reported in Kingdom of Bahrain, of NMO with positive NMO IgG and favorable response to Rituximab. Methods and results Case # 1: 56 year old female patient. She had on 2008 left optic neuritis with residual visual loss. On September 2011 she had right optic neuritis. For both she received Methylprednisolone plus therapy for 4 days with partial response and residual visual loss. On October 2011, she developed severe myelitis with severe spastic paraplegia (grade 0–1) and urinary retention. The patient became bed bound. Her initial MRI of brain showed few scattered lesions for which the patient was diagnosed as multiple sclerosis and maintained on Betaferon injection as a disease modifying therapy. The repeated MRI showed long segment lesion of the spinal cord and her blood test was positive to NMO IgG. The patient did not respond to steroid or IVIg therapy. However, she responded remarkably well to Rituximab injection. In 3 months she is fully independent in her movements with almost normal power and continent. Case # 2: 43 year old female patient. On 2009, she developed a right optic neuritis that responded well to steroid therapy. 2 years later she developed spastic Paraparesis due to myelitis, she responded partially to steroid therapy and was put on Avonex injection as her MRI brain showed changes was diagnosed as MS in private hospital. However, one year later, she developed another sever myelitis that made her wheelchair bound with bladder involvement. Her MRI showed fairly long segment involvement of spinal cord. Her serum test showed positive NMO IgG. I gave her Rituximab injection therapy on which she showed remarkable improvement. In 3 months she is able to walk by herself and she independent in her ADL and bladder continent. Conclusion The remarkable recovery of these 2 patients from their severe disability in this case report support other reports of the effectiveness of Rituximab in the treatment of NMO and the humoral immunity nature of the illness. These are the first cases of NMO with positive IgG to be reported from Bahrain. NMO is not often seen in Bahrain despite high prevalence of MS.