Occurrence and treatment of myasthenia gravis

Autoantibodies Lead to Abnormal Transmission of Neuromuscular Junction

The human body must rely on the normal neuromuscular junction transmission process (shown in the question figure) when completing each skeletal muscle contraction activity.

The neuromuscular junction consists of (1) (presynaptic motor nerve endings), (2) (postsynaptic muscle cell membrane) and the synaptic gap between the two. When a motor command is transmitted from (1), It will activate ③ (synaptic vesicles) to release the chemical transmitter acetylcholine into synaptic spaces, and when acetylcholine moves to ② (postsynaptic muscle cell membrane) through the spaces, it will combine with ④ (acetylcholine receptor) above to further activate ⑤ (mitochondria in muscle cells), thus completing muscle contraction and executing movement instructions.

The cause of myasthenia gravis lies in the abnormal function of the immune system in the patient’s body, which produces abnormal autoantibodies and hinders the normal combination of acetylcholine and ④ (acetylcholine receptor), thus leading to the inability to effectively issue exercise instructions and causing symptoms of muscle weakness.

Myasthenia gravis is a treatable disease

Under the correct and regular treatment, most patients can basically maintain a relatively normal living condition.

Its treatment is divided into symptomatic treatment, immunosuppressive treatment, immunomodulatory treatment and thymectomy treatment.

Symptomatic treatment mainly uses bromopyridostigmine.

Immunosuppressive therapy includes glucocorticoid (prednisone, dexamethasone or methylprednisone), azathioprine, cyclophosphamide, tacrolimus, cyclosporine, etc.

Immunomodulatory therapy includes human gamma globulin and plasma exchange (or filtration);

Thymectomy is mainly suitable for patients with thymic hyperplasia over 18 years old with poor systemic therapeutic effect and thymoma. Thymectomy is not recommended for children or adolescents with thymic hyperplasia.

Author: Huashan myopathy group

The article was reprinted by Clove Garden authorized by the author.