Clinical features and outcome of multifocal motor neuropathy: a single-center follow-up study
10.3760/cma.j.cn113694-20250416-00214
- VernacularTitle:多灶性运动神经病的临床特征及治疗转归：一项单中心随访研究
- Author:
Siqi SHANG
1
;
Kai QIAO
1
;
Jian SUN
1
;
Chong SUN
1
;
Chongbo ZHAO
1
;
Jie LIN
1
Author Information
1. 复旦大学附属华山医院神经内科 复旦大学附属华山医院罕见病中心 国家神经疾病医学中心，上海 200040
- Publication Type:Journal Article
- Keywords:
Multifocal motor neuropathy;
Gangliosides;
Immunoglobulins, intravenous;
Plasma exchange;
Rituximab
- From:
Chinese Journal of Neurology
2025;58(9):946-955
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the clinical characteristics, treatment status, and disease outcomes of Chinese patients with multifocal motor neuropathy (MMN).Methods:Inpatients with MMN who were admitted to Huashan Hospital, Shanghai Medical College, Fudan University between January 2014 and April 2024 were enrolled. Baseline information, clinical features, and treatment history were recorded. Disability and functional impairment were assessed using the Inflammatory Neuropathy Cause and Treatment (INCAT) scale.Results:A total of 39 MMN patients were included and classified according to the 2010 European Federation of Neurological Societies/Peripheral Nerve Society criteria: definite MMN (27 cases), probable MMN (3 cases), and possible MMN (9 cases). At onset, 29 cases (29/39, 74.4%) had unilateral upper limb involvement, 5 cases (5/39, 12.8%) had unilateral lower limb involvement, 1 case (1/39, 2.6%) had bilateral lower limb involvement, and 4 cases (4/39, 10.3%) had simultaneous upper and lower limb involvement. By the last follow-up, follow-up duration was 3.4 (5.4) years (range: 0-14.3 years), disease duration was 8.3 (5.9) years (range: 1.2-31.3 years); 27 patients (27/39, 69.2%) exhibited increased limb involvement compared to onset. Segmental conduction block was detected in 35 cases (35/39, 89.7%). Anti-GM1 IgM antibodies were positive in 14 cases (14/31, 45.2%), and cerebrospinal fluid protein-cell dissociation was observed in 6 cases (6/32, 18.8%). Among them, 38 patients were treated with intravenous immunoglobulin (IVIG) during the disease course. Among the 24 patients followed up for>1 year after IVIG initiation, long-term efficacy (≥1 year), medium-short-term efficacy (<1 year), and no efficacy were observed in 16.7% (4/24), 62.5% (15/24), and 20.8% (5/24) of cases, respectively. Patients with persistently positive anti-GM1 IgM antibodies tended to have medium-short-term relief. Cyclophosphamide was used in 7 cases, with long-term improvement in 1 case. One patient achieved sustained improvement after two courses of rituximab. No benefit was observed with plasma exchange, corticosteroids, or other immunosuppressants. The median INCAT score at disease onset was 1 (range: 0-4), while the median pre-immunotherapy INCAT score was 3 (range: 0-5), and at the last follow-up after treatment, the median INCAT score remained 3 (range: 0-5). A statistically significant increase in INCAT scores was observed from disease onset to pretreatment ( U=229.000, P<0.001). However, no statistically significant difference was found between pretreatment and posttreatment INCAT scores ( U=491.500, P=0.880). Conclusions:MMN is a slowly progressive immune-mediated peripheral neuropathy. Early diagnosis and treatment with IVIG are crucial. Evidence for the efficacy of cyclophosphamide and rituximab remains limited.
