Differential diagnosis between NMOSD and MS: a retrospective study based on clinical and imaging features

Neuromyelitis optica spectrum disorders (NMOSD) and multiple sclerosis (MS) are both inflammatory demyelinating diseases of the central nervous system, sharing many similarities in clinical manifestations. However, they differ significantly in terms of etiology, pathological mechanisms, treatment, and prognosis. Since early clinical differentiation can be challenging, achieving an accurate diagnosis at the initial stage of disease onset is particularly critical. Therefore, a thorough analysis of patients' clinical characteristics is of great importance in assisting clinicians with early diagnosis and treatment, ultimately contributing to improved patient outcomes.

Clinical data were collected for patients who were first diagnosed with NMOSD or MS at the General Hospital and the Cardiovascular and Cerebrovascular Hospital of Ningxia Medical University between January 2018 and January 2022. Collected information included demographic data, past medical history, initial clinical symptoms, physical examination findings, laboratory tests, imaging studies, and three types of evoked potentials. Patients were followed up for relapse during remission, presence of residual symptoms, medication use, and scores on the Extended Disability Status Scale (EDSS). The clinical characteristics of the two diseases were summarized and the results subjected to statistical analysis.

This study conducted a comparative analysis across multiple indicators, comprehensively revealing significant differences in the clinical characteristics of NMOSD and MS. The results showed that the proportion of female patients was significantly higher in the NMOSD group (86.2%) compared with the MS group (69.0%), with a statistically significant difference (p = 0.035). In terms of clinical manifestations, NMOSD patients more frequently presented with comorbid autoimmune diseases, initial symptoms, and neurological signs at admission, all of which were more severe and common than in MS patients, with statistically significant differences. The severity of neurological dysfunction in NMOSD patients during the acute phase was also markedly greater than that observed in MS patients, as confirmed by comparisons of the EDSS scores. Laboratory examinations further demonstrated fundamental differences between NMOSD and MS in cerebrospinal fluid characteristics, specific antibodies, and other serological markers, providing important evidence for differential diagnosis. In addition, imaging and electrophysiological findings indicated that MS lesions were predominantly located in the brain, whereas NMOSD lesions mainly involved the optic nerve and spinal cord. Notably, NMOSD patients exhibited more extensive spinal cord involvement and more frequent impairment of the visual pathway.

Although NMOSD and MS share many similarities in clinical symptoms, they differ substantially in their fundamental characteristics, as reflected in demographic features, clinical manifestations, laboratory and imaging findings, as well as prognosis. Compared with MS, NMOSD patients are typically older at disease onset, have a higher proportion of females, and experience more frequent relapses and greater disability. In terms of imaging, MS lesions are predominantly distributed in the brain, whereas NMOSD mainly involves the optic nerve and spinal cord. Therefore, early differentiation between the two diseases in clinical practice is essential for developing targeted treatment strategies and ultimately improving patient outcomes.