External factors are environmental factors around us. After some clinical studies by experts, it is found that some environmental factors, such as environmental pollution, will reduce human immunity; Overwork leads to immune dysfunction; Virus infection or the use of aminoglycoside antibiotics or D- penicillamine and other drugs induce some gene defects.
Second, internal factors
Internal factors refer to genetic factors. Myasthenia is an autoimmune disease, which is influenced by some genetic factors. Myasthenia is not only related to major histocompatibility antigen complex genes, but also related to incompatibility antigen complex genes, and related to the etiology of myasthenia such as T cell receptor, immunoglobulin, cytokines, apoptosis and other genes.
Third, the autoimmune system is abnormal
In some clinical studies of myasthenia gravis, experts found that most patients had abnormal autoimmune indexes. After some timely treatment, even if the clinical symptoms disappear, the abnormal immune indexes have not changed, which may be the reason why myasthenia gravis is unstable and prone to recurrence.