American Board of Internal Medicine (ABIM) Certification Practice Exam

Which treatment can worsen the symptoms of Myasthenia Gravis initially?

1. Anticholinesterase inhibitors

2. High-dose glucocorticoids

3. Intravenous immunoglobulin

4. Plasmapheresis

The correct answer is: High-dose glucocorticoids

High-dose glucocorticoids can worsen the symptoms of Myasthenia Gravis initially due to their immunosuppressive effects. While glucocorticoids are commonly used in the management of autoimmune conditions, their introduction can lead to an exacerbation of symptoms in patients with Myasthenia Gravis, especially during the initial phase of treatment. This occurs because glucocorticoids can temporarily increase the levels of circulating immunoglobulins, potentially contributing to a transient worsening of the autoimmune process before any benefits from their immunosuppressive actions are realized. Additionally, the other treatments listed typically do not cause an initial exacerbation of symptoms. Anticholinesterase inhibitors are designed to improve neuromuscular transmission and relieve weakness. Intravenous immunoglobulin and plasmapheresis are often used to provide rapid temporary improvements in symptoms by reducing the circulating antibodies that interfere with neuromuscular transmission. Therefore, while glucocorticoids are effective in the long-term management of Myasthenia Gravis, their initial use can inadvertently lead to symptom worsening in some patients.