Clinical characteristics and prognosis of stiff-person syndrome associated with glutamic acid decarboxylase 65 antibodies: a case series from China
10.3760/cma.j.cn113694-20231221-00394
- VernacularTitle:抗谷氨酸脱羧酶抗体相关僵人综合征33例临床与预后分析
- Author:
Lin BAI
1
;
Hongzhi GUAN
;
Siyuan FAN
;
Haitao REN
;
Yuzhou GUAN
;
Yingmai YANG
;
Yicheng ZHU
;
Liying CUI
Author Information
1. 中国医学科学院北京协和医学院北京协和医院神经科，北京 100730
- Keywords:
Glutamate decarboxylase;
Stiff-person syndrome;
Immunotherapy;
Neuronal antibodies
- From:
Chinese Journal of Neurology
2024;57(9):993-999
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze the clinical characteristics and prognosis of patients with stiff-person syndrome (SPS) associated with glutamic acid decarboxylase (GAD) antibodies.Methods:A retrospective analysis was conducted on demographic characteristics, clinical manifestations, auxiliary examination results, treatment, and prognosis of patients with GAD antibody-related SPS treated at Peking Union Medical College Hospital from January 2015 to July 2023.Results:A total of 33 patients were included, comprising 26 females (78.8%) and 7 males (21.2%), with an onset age of (42±12) years and a disease duration of 24.0 (10.5, 37.5) months. Two cases (6.1%) were diagnosed with tumors, including 1 case with invasive thymoma and 1 case with small cell lung cancer. The majority of patients (87.9%, 29/33) presented with stiffness of trunk and proximal limb muscles, 42.4% (14/33) of patients exhibited episodic spasm, and 54.5% (18/33) of patients were triggered by stimuli such as sound and light. Babinski or Chaddock reflexes were elicited in 33.3% (11/33) of patients. Some patients (36.4%, 16/33) had concurrent limbic encephalitis/epilepsy or cerebellar ataxia (referred to as complex SPS). The median cerebrospinal fluid (CSF) white blood cell count was 2×10 6/L [quartile: 1×10 6/L, 6×10 6/L; range: (0-30)×10 6/L], with mild elevation in 28.0% (7/25) of patients. Multi-channel surface electromyography in 14 out of 21 cases (66.7%) suggested synchronous contraction of agonist and antagonist muscles in a relaxed state. The modified Rankin Scale (mRS) score during the acute phase was 4 (3, 4). All patients received treatment with benzodiazepines or baclofen. Thirty patients (90.9%, 30/33) received first-line immunotherapy, 3 patients (9.1%, 3/33) received second-line immunotherapy with rituximab, and 14 (42.4%, 14/33) received mycophenolate mofetil as long-term immunotherapy. The follow-up period was 16 (10, 42) months, with a median best mRS score of 2; 66.7% (22/33) of patients had a favorable functional prognosis (mRS score≤2), and the recurrence rate was 30.0% (9/30). At the last follow-up, the median mRS score was 2, and 53.3% (16/30) of patients had a favorable functional prognosis. Prognosis was not significantly correlated with gender, age, clinical type, or CSF white blood cell level (all P>0.05). Conclusions:SPS is one of the main clinical phenotypes of GAD antibody-related neuroimmune diseases, commonly observed in middle-aged women, and exhibits a chronic progressive course. Only a minority of patients have concomitant tumors. The diagnosis relies on typical symptoms, GAD antibody testing, and electromyography examination. The initial immune therapy yields good results, but the prognosis for recurrent patients is poor.
