Myasthenia Gravis

Myasthenia gravis is a disorder of neuromuscular transmission, manifest by variable weakness of skeletal muscle. The disorder has a range of therapies that differ with respect to efficacy, timing, and side effects. The physician treating myasthenia gravis must be well versed in understanding the evidence basis for using these agents, as well as the trade-offs between persistent disease manifestations and their costs and expected benefits. Diagnosis of myasthenia gravis depends on recognizing the pattern of weakness, which typically involves some combination of extraocular, bulbar, facial, limb, and neck muscles. Management relies on some combination of medications that influence the function of the neuromuscular junction and treatments that alter the immune response. Thymectomy is commonly used, although trends in evidence-based medicine are leading expert clinicians to look closely at its efficacy. Plasma exchange is useful for patients in crisis, who require rapid improvement. The exact role for high-dose intravenous immunoglobulin in this setting is still being studied, although the agent is gaining popularity. Knowing that the treatments are effective is not enough. It is still important to determine the treatment that has a more rapid onset, because these patients often require intensive care or respiratory assistance.