Electrophysiological Insights: Using Repetitive Nerve Stimulation to Monitor Clinical Status and Remission in Myasthenia Gravis

• Published in: Neurological sciences and neurophysiology 2024-07, Vol.41 (3), p.176-181
• Main Authors: Tunç, Abdulkadir, Güngen, Belma Doğan, Öncel, Samet, Sivaci, Ali Özhan
• Format: Article
• Language: English
• Subjects: decreased; electromyography; generalized myasthenia gravis; prognosis; repetitive nerve stimulation
• ISSN: 2636-865X; 2636-865X
• DOI: 10.4103/nsn.nsn_66_24

Objective: Myasthenia gravis (MG) is a chronic autoimmune neuromuscular disorder with a variable course that complicates the prediction of remission. This study aimed to evaluate the utility of repetitive nerve stimulation (RNS) in monitoring clinical status through the assessment of decremental response rates in the nasalis and trapezius muscles during treatment. Subjects and Methods: A prospective study was conducted with 52 patients diagnosed with generalized MG. Patients underwent clinical assessments, including tests for anti-acetylcholine receptor and anti-muscle-specific kinase antibodies, and were classified according to the Myasthenia Gravis Foundation of America classification. Electrophysiological testing through RNS and single-fiber electromyography was performed. Data analysis involved comparing the RNS decrement rates with clinical and demographic variables. Follow-up for assessing remission spans 2 years. Results: Among the 52 patients, 53.8% achieved clinical remission. In the remission group, 14.3% of the patients exhibited a decremental response compared with 70.8% in the nonremission group, particularly in the nasalis and trapezius muscles, in the follow-up RNS conducted 2 years after the initial assessment (P < 0.05). The remission group presented significantly lower rates of antibody positivity and less bulbar involvement. Interestingly, initial clinical severity did not correlate significantly with remission. Conclusion: This study demonstrated the usefulness of RNS in assessing the clinical status of MG patients and evaluating the effectiveness of current therapeutic strategies. These findings suggest that focusing on specific muscle responses in RNS can provide valuable information for patient management.