Systemic Lupus Erythematosus with Neuromyelitis Optica

Systemic lupus erythematosus (SLE) is an autoimmune disease that can have detrimental effects on many different systems in the body, including the central nervous system. Neuropsychiatric SLE (NPSLE) refers to several different neurological and/or behavioral clinical syndromes, and has been reported as having a prevalence rate of approximately 30−40%, while manifestation of myelitis or optic neuritis of NPSLE is rare (~1%). Myelitis and optic neuritis are easily identifiable since myelitis is frequently transverse, and manifests as severe disturbances in both motor and sensory pathways, while optic neuritis is often both bilateral and severe. At least 85% of patients experience relapses in the form of optic neuritis, transverse myelitis, or both. Furthermore, some cases of NPSLE with optic neuritis are often complicated by myelitis. Interestingly, the characteristics of myelitis or optic neuritis in NPSLE are quite similar to neuromyelitis optica (NMO), a disease characterized by bilateral optic neuropathy and transverse myelopathy. In fact, magnetic resonance imaging (MRI) of patients with NPSLE has demonstrated longitudinal spinal involvement showing cord swelling and hyperintense lesions in central regions. These findings are also typically observed in MRIs of patients with NMO. Additionally, anti-aquaporin 4 (AQP4) antibodies have been discovered in patients with NMO and with NPSLE with myelitis and/or optic neuritis. Therefore, complications that are often encountered with NMO should be considered when treating cases of NPSLE with myelitis and/or optic neuritis. Moreover, since the treatment of NMO closely resembles the therapeutic approaches taken for NPSLE, corticosteroids alone or in combination with immunosuppressants could prove effective in reducing incidents of relapse. Some patients, however, may be refractory to steroid therapy; in such cases, plasma exchange may have priority over other second-line therapeutic strategies, such as intravenous immunoglobulin and rituximab, because of treatment approaches typically employed in NMO. In this review, I will discuss pathological similarities between NPSLE with myelitis and/or optic neuritis and NMO with the aim of demonstrating that our knowledge of NMO should be considered when treating NPSLE with myelitis and/or optic neuritis.