Frequency of new asymptomatic MRI lesions during attacks and follow-up of patients with NMOSD in a real-world setting

Moving towards a new era for the treatment of neuromyelitis optica spectrum disorders

Neuromyelitis optica spectrum disorders (NMOSD) include a rare group of autoimmune conditions that primarily affect the central nervous system. They are characterized by inflammation and damage to the optic nerves, brain and spinal cord, leading to severe vision impairment, locomotor disability and sphynteric disturbances. In the majority of cases, NMOSD arises due to specific serum immunoglobulin G (IgG) autoantibodies targeting aquaporin 4 (AQP4-IgG), which is the most prevalent water-channel protein of the central nervous system. Early diagnosis and treatment are crucial to manage symptoms and prevent long-term disability in NMOSD patients. NMOSD were previously associated with a poor prognosis. However, recently, a number of randomized controlled trials have demonstrated that biological therapies acting on key elements of NMOSD pathogenesis, such as B cells, interleukin-6 (IL-6) pathway, and complement, have impressive efficacy in preventing the occurrence of clinical relapses. The approval of the initial drugs marks a revolutionary advancement in the treatment of NMOSD patients, significantly transforming therapeutic options and positively impacting their prognosis. In this review, we will provide an updated overview of the key immunopathological, clinical, laboratory, and neuroimaging aspects of NMOSD. Additionally, we will critically examine the latest advancements in NMOSD treatment approaches. Lastly, we will discuss key aspects regarding optimization of treatment strategies and their monitoring.

Asymptomatic spinal lesions in patients with AQP4-IgG-positive NMOSD: A real-world cohort study

OBJECTIVE

This study aims to explore the frequency and influencing factors of asymptomatic spinal lesions (ASLs) and their impact on subsequent relapses in patients with AQP4-IgG-positive NMOSD (AQP4-NMOSD) in a real-world setting.

METHODS

We retrospectively reviewed clinical information and spinal MRI data from AQP4-NMOSD patients who had at least one spinal cord MRI during their follow-ups. Kaplan-Meier curves and Cox proportional hazards models were employed to ascertain potential predictors of remission ASLs and to investigate factors associated with subsequent relapses.

RESULTS

In this study, we included 129 patients with AQP4-NMOSD and reviewed 173 spinal MRIs during attacks and 89 spinal MRIs during remission. Among these, 6 ASLs (3.5%) were identified during acute attacks, while 8 ASLs (9%) were found during remission. Remission ASLs were linked to the use of immunosuppressive agents, particularly conventional ones, whereas no patients using rituximab developed ASLs (p = 0.005). Kaplan-Meier curve analysis indicated that patients with ASLs had a significantly higher relapse risk (HR = 4.658, 95% CI: 1.519-14.285, p = 0.007) compared to those without. Additionally, the use of mycophenolate mofetil (HR = 0.027, 95% CI: 0.003-0.260, p = 0.002) and rituximab (HR = 0.035, 95% CI: 0.006-0.203, p < 0.001) significantly reduced the relapse risk. However, after accounting for other factors, the presence of ASLs did not exhibit a significant impact on subsequent relapses (HR = 2.297, 95% CI: 0.652-8.085, p = 0.195).

INTERPRETATION

ASLs may be observed in patients with AQP4-NMOSD. The presence of ASLs may signify an underlying inflammatory activity due to insufficient immunotherapy. The administration of immunosuppressive agents plays a key role in the presence of remission ASLs and the likelihood of subsequent relapses.