意义未明的单克隆丙种球蛋白血症相关周围神经病的临床和神经电生理特点研究

The Clinical and Electrophysiological Characteristics of Monoclonal Gammopathy of Unknown Significance Associated Peripheral Neuropathy

目的分析意义未明的单克隆丙种球蛋白血症(MGUS)相关周围神经病(PN)的临床及电生理特点。方法收集21例2016至2019年在复旦大学附属华山医院神经内科和血液科确诊的MGUS-PN患者临床资料,按是否表达抗髓鞘相关糖蛋白抗体(MAG)分为:MAG阳性IgM MGUS-PN组(9例),MAG阴性IgM MGUS-PN组(4例)和非IgMMGUS-PN组(8例)。总结、分析患者的临床特点和神经电生理特点,比较MGUS-PN亚型间的临床特点。结果(1)MAG阳性IgM MGUS-PN组均为男性,平均起病年龄(57.9±7.5)岁。临床表现:9例均有四肢远端麻木,伴肢体无力5例,Romberg征阳性5例。电生理表现:脱髓鞘伴轴索改变5例,以轴索改变为主3例。(2)MAG阴性IgM MGUS-PN组中男性2例,平均起病年龄(68.0±8.9)岁。临床表现:四肢远端麻木4例,伴肢体无力3例,Romberg征阳性2例;电生理表现:脱髓鞘改变为主3例。(3)非IgM MGUS-PN组均为男性(IgA 2例,IgG 6例),平均起病年龄(48.5±12.9)岁。临床表现:肢体远端麻木感7例,伴肢体无力6例,Romberg征阳性4例;电生理表现:脱髓鞘损害5例,轴索损害1例,根性损害1例。结论MGUS-PN多为中老年起病,病程呈慢性进展性。肢体远端感觉受累为主要为临床表现,伴或不伴肢体无力。MGUS-PN各亚型在病程和起病年龄上稍有不同,神经电生理特点无差异。

Aim To investigate the clinical and electrophysiological characteristics of monoclonal gammopathy of unknown significance associated peripheral neuropathy(MGUS-PN).Methods Retrospectively analyzing the clinical and electrophysiological characteristics of MGUS-PN patients from Huashan Hospital,Fudan University between 2016 and 2019.Results Twenty-one patients with MGUS-PN were summarized.Of thirteen IgM MGUS-PN patients,nine presented with positive anti-myelin associated glycoprotein antibody(anti-MAG antibody).All anti-MAG peripheral neuropathy patients were male and the average age of onset was 57.9±7.5 years.Nine(100%)patients presented as distal limb numbness,five(55.6%)patients of them had muscle weakness and five(55.6%)were positive in Romberg sign.Among eight patients experienced nerve conduction study,five(62.5%)patients presented as demyelination pattern with secondary axonal degeneration,while three(37.5%)patients had predominant axonal damage.Four cases were diagnosed with Ig M MGUS-PN with anti-MAG antibody negative.Two(50.0%)of them were male and the average age of onset was(68.0±8.9)years.Four patients(100%)presented as distal limb numbness,three(75.0%)patients had muscle weakness and two patients were positive in Romberg sign.Three patients(75.0%)experienced nerve conduction study and all of them presented as demyelination damage.Of eight non-Ig M MGUS-PN patients,two cases were diagnosed with Ig A MGUS-PN and six were Ig G MGUS-PN.All non-Ig M MGUS-PN cases were male and the average age of onset was(48.5±12.9)years.Seven(87.5%)patients presented as distal limb numbness,six(75.0%)patients of whom had muscle weakness and four(50.0%)patients were positive in Romberg sign.Among seven patients experienced nerve conduction study,five cases(71.4%)presented as demyelination damage,one case(14.3%)had predominant axonal damage and one(14.3%)with nerve root damage.Conclusion MGUS-PN is in favor of the elder with a slow and progressive course.MGUS PN is typically characterized by distal and symmetric paresthesia with or without mildly distal muscle weakness.Different subtype of MGUS-PN differs mildly on the age of onset and the duration from onset to diagnosis,but no significant differences were found on electrophysiological characteristics.