摘要：

研究背景 多系统萎缩是主要累及锥体外系、小脑和自主神经系统的神经变性病，临床主要表现为帕金森综合征、小脑共济失调、自主神经功能障碍等，亦可累及下丘脑及其联系纤维，导致抗利尿激素分泌不当综合征和低钠血症。本研究总结多系统萎缩伴抗利尿激素分泌不当综合征的临床特点，以为临床诊断与治疗提供依据。方法 回顾分析2011-2015 年在北京协和医院神经科门诊和住院治疗的3 例多系统萎缩伴抗利尿激素分泌不当综合征患者的临床表现、实验室和影像学特点及诊断与治疗经过。结果 3 例多系统萎缩患者中2 例为以帕金森综合征为主要表现型，1 例为以小脑共济失调为主要表现型；均合并严重低钠血症，血清钠最低为123、118 和121 mmol/L，24 h 尿钠分别为91、114 和129 mmol/L，1 例明确诊断为抗利尿激素分泌不当综合征，2 例可疑抗利尿激素分泌不当综合征；2 例合并感染，1 例为嗜肺军团菌感染、1 例为肺部感染，予抗感染和限水补钠对症支持治疗后预后良好，余1 例至疾病终末期出现顽固性低钠血症而死亡。结论 多系统萎缩自身或合并感染可能是抗利尿激素分泌不当综合征的易感因素，应加强对多系统萎缩患者水钠平衡的管理。多系统萎缩伴抗利尿激素分泌不当综合征临床罕见，一旦出现顽固性低钠血症则提示预后不良。

关键词: 多系统萎缩, ADH 分泌不当综合征, 低钠血症

Abstract:

Background Multiple system atrophy (MSA) is a neurodegenerative disorder affecting motor (either extrapyramidal or cerebellar) and autonomic nervous systems. The main clinical manifestations of MSA are parkinsonism, cerebellar ataxia and autonomic dysfunction. It may also affect the hypothalamus and related fibers, resulting in syndrome of inappropriate antidiuretic hormone secretion (SIADH) and hyponatremia. This study aims to identify the clinical characteristics of MSA with SIADH, so as to provide evidence for clinical diagnosis and treatment. Methods Clinical manifestations, laboratory examinations and imaging features, diagnosis and treatment of 3 MSA patients with SIADH in our hospital from 2011 to 2015 were retrospectively analyzed. Results Among 3 MSA patients, 2 cases were parkinsonism-predominant (MSA-P) and the other one was cerebellar-predominant (MSA-C). All of them presented severe hyponatremia. The lowest serum sodium concentration was 123, 118 and 121 mmol/L, respectively. The level of urinary sodium concentration was 91, 114 and 129 mmol/L, respectively. One was diagnosed as definite SIADH, and the other 2 cases were possible SIADH. Two cases were complicated with infection (one Legionella pneumophila and one pulmonary infection), which was greatly improved after anti-infection treatment and sodium supplement. The other case died of refractory hyponatremia in the end. Conclusions MSA patients with autogenous or concurrent infection may be susceptible to SIADH, therefore water-sodium balance management is important for MSA patients. MSA with SIADH is rare, and refractory hyponatremia may indicate a poor prognosis.

Key words: Multiple system atrophy, Inappropriate ADH syndrome, Hyponatremia