Abstract
OBJECTIVE: This study aimed to investigate the clinical characteristics of patients with myasthenia gravis (MG) who are double-seropositive for acetylcholine receptor antibodies (AChR-Ab(+)) and titin antibodies (Titin-Ab(+)). METHODS: A retrospective analysis was conducted on MG patients hospitalized in the Department of Neurology between March 2020 and June 2024. Patients were categorized into two groups based on antibody profiles: those with AChR antibody positivity alone and those with dual positivity for AChR and titin antibodies. Clinical features, MG classification, and treatment outcomes were compared between the two groups. RESULTS: A total of 35 MG patients were included, comprising 18 with single AChR-Ab(+) and 17 with AChR-Ab(+)/Titin-Ab(+). The dual antibody-positive group showed a significantly higher proportion of patients with MGFA classification above Class II (47.1%) and a higher rate of thyroid dysfunction (50%) compared to the single antibody-positive group (p = 0.001). The median age of onset in the dual antibody-positive group was older than that in the single antibody-positive group (67.0 years vs. 58.5 years), although this difference was not statistically significant (p > 0.05). No significant differences were observed between the two groups in terms of gender, initial symptoms, clinical manifestations, thymic hyperplasia, proportion of thymoma, treatment regimens, or therapeutic outcomes (all p > 0.05). CONCLUSION: This study provides the first systematic characterization of the clinical profile of AChR-Ab(+)/Titin-Ab(+) myasthenia gravis patients in Southwest China. Our findings indicate that dual antibody-positive MG patients are more prone to generalized disease involvement and have a higher susceptibility to thyroid dysfunction.