American Board of Internal Medicine (ABIM) Certification Practice Exam

What are the initial treatments for myasthenic crisis?

1. Oral immunosuppressants

2. Intravenous immune globulin and plasmapheresis

3. Intravenous steroids and high-dose plasmapheresis

4. Close observation without immediate intervention

The correct answer is: Intravenous immune globulin and plasmapheresis

In the context of myasthenic crisis, which is characterized by severe muscle weakness and respiratory failure due to exacerbated myasthenia gravis, the initial treatments focus on rapidly improving muscle strength and providing respiratory support. Intravenous immune globulin (IVIG) and plasmapheresis are well-supported treatment modalities for this acute condition because they can quickly reduce circulating antibodies and improve symptoms. Plasmapheresis involves the removal of the patient's blood plasma, which contains the autoantibodies that interfere with neuromuscular transmission. This procedure can lead to a swift decrease in muscle weakness. Similarly, IVIG works by modulating the immune response and reducing the autoimmune attack on the neuromuscular junction. The combination of these two treatments is particularly effective in addressing the urgent nature of a myasthenic crisis, where the goal is to stabilize the patient as promptly as possible, especially with regards to breathing difficulties. Thus, IVIG and plasmapheresis are recognized as important initial interventions in managing myasthenic crisis.