Voltage-gated potassium channel-complex antibodies associated clinical syndromes with myasthenia gravis complicated with thymoma: analysis of 2 cases and literature review / 中华神经科杂志

ABSTRACT

Objective:To investigate the clinical characteristics and outcome of patients with voltage-gated potassium channel complex (VGKCc) antibody associated clinical syndromes complicated with myasthenia gravis (MG) with thymoma.Methods:The clinical history, examinations and follow-up prognosis of 2 cases of VGKCc antibodies associated clinical syndromes with MG complicated with thymoma in Qilu Hospital (Qingdao), Cheeloo College of Medicine,Shandong University in September 2020 and December 2020 were reviewed. Related literatures were summarized at the same time.Results:Case 1, a 64-year-old female clinically presented with cognitive impairment, psychosis, and epilepsy seizures, whose serum autoimmune antibody testing showed positive leucine-rich glioma-inhibited 1 (LGI1) antibody, was diagnosed as anti-LGI1 encephalitis,and had history of MG with thymoma. Her symptoms were improved by immunotherapy. Case 2, a 67-year-old male, was diagnosed as MG, and developed cognitive impairment, myokymia and autonomic dysfunction later. His serum autoimmune antibody testing showed positive contactin associated protein-like 2 antibody. Therefore, Morvan syndrome complicated with MG with thymoma was definitely diagnosed. After admission, the patient was improved with immunotherapy and thymoma resection.Conclusions:Patients with VGKCc antibody-associated clinical syndromes complicated with MG have the clinical characteristics of the two diseases simultaneously, and there is also crossover. Immunotherapy and treatment for thymoma are generally effective.