Update on the diagnosis and treatment of neuromyelitis optica: Recommendations of the Neuromyelitis Optica Study Group (NEMOS)

Abstract

Neuromyelitis optica (NMO, Devic’s syndrome), long considered a clinical variant of multiple sclerosis, is now regarded as a distinct disease entity. Major progress has been made in the diagnosis and treatment of NMO since aquaporin-4 antibodies (AQP4-Ab; also termed NMO-IgG) were first described in 2004. In this review, the Neuromyelitis Optica Study Group (NEMOS) summarizes recently obtained knowledge on NMO and highlights new developments in its diagnosis and treatment, based on current guidelines, the published literature and expert discussion at regular NEMOS meetings. Testing of AQP4-Ab is essential and is the most important test in the diagnostic work-up of suspected NMO, and helps to distinguish NMO from other autoimmune diseases. Furthermore, AQP4-Ab testing has expanded our knowledge of the clinical presentation of NMO spectrum disorders (NMOSD). In addition, imaging techniques, particularly magnetic resonance imaging of the brain and spinal cord, are obligatory in the diagnostic workup. It is important to note that brain lesions in NMO and NMOSD are not uncommon, do not rule out the diagnosis, and show characteristic patterns. Other imaging modalities such as optical coherence tomography are proposed as useful tools in the assessment of retinal damage. Therapy of NMO should be initiated early. Azathioprine and rituximab are suggested as first-line treatments, the latter being increasingly regarded as an established therapy with long-term efficacy and an acceptable safety profile in NMO patients. Other immunosuppressive drugs, such as methotrexate, mycophenolate mofetil and mitoxantrone, are recommended as second-line treatments. Promising new therapies are emerging in the form of anti-IL6 receptor, anti-complement or anti-AQP4-Ab biologicals.

Present and Future Therapies in Neuromyelitis Optica Spectrum Disorders

“…Acute exacerbations of NMOSD are usually treated with high-dose intravenous (IV) methylprednisolone (IVMP) at a dose of 1000 mg for 3-5 days with or without oral tapering [8,[24][25][26]. It has been shown that each, a first, second, and third course of IVMP significantly improves clinical disability in patients with MS and NMOSD [34], and that early administration is associated with preservation of the retinal nerve fiber layer thickness in NMOSD [35].…”

“…Several clinical features highly distinctive for NMO and NMOSD have been identified, which include simultaneous LETM and optic neuritis (ON), bilateral ON, and intractable nausea with hiccups and vomiting [7]. Besides clinical evaluation, AQP4-IgG serology and MRI, cerebrospinal fluid diagnostics, evoked potentials, and optical coherence tomography guide diagnosis of NMO and NMOSD [8].…”

“…Several national and international guidelines describing diagnosis and treatment of NMOSD have been published [8,[24][25][26][27]], yet most therapeutic recommendations are still expert-based because until recently all studies reporting treatment outcomes had been conducted in a nonrandomized and often retrospective setting.…”

Immunotherapies for Neurological Manifestations in the Context of Systemic Autoimmunity

“…Spinal cord involvement due to ectopical calcinosis has been observed in only a few cases [112]. In cases where concurrent antiaquaporin 4-positive disease is present, treatment is according to the recommendations of the Neuromyelitis Optica Study Group [113].…”

Neuromyelitis optica does not impact periventricular venous density versus healthy controls: a 7.0 Tesla MRI clinical study

“…Prior to the discovery of a serum immunoglobulin G antibody targeting the aquaporine-4 water channel [5,6], it was often considered a variant of multiple sclerosis (MS) as the clinical presentation of these two distinct central nervous system (CNS) diseases may overlap [1]. Indeed, patients with NMOSD are still often misdiagnosed with MS in clinical practice [7,8].…”