Neuromuscular Junction and Myasthenia Gravis.docx

**Neuromuscular Junction and Myasthenia Gravis** **Introduction to Neuromuscular Diseases** - Recap: Previously covered peripheral neuropathy types like plexopathy, mononeuropathy, and polyneuropathies. **Neuromuscular Junction Diseases** - Focuses on conditions affecting the neuromuscul...

**Neuromuscular Junction and Myasthenia Gravis** **Introduction to Neuromuscular Diseases** - Recap: Previously covered peripheral neuropathy types like plexopathy, mononeuropathy, and polyneuropathies. **Neuromuscular Junction Diseases** - Focuses on conditions affecting the neuromuscular junction, where nerves meet muscles. **Myasthenia Gravis (MG):** MG is a complex autoimmune disease affecting the neuromuscular junction, leading to muscle weakness that varies in severity. - **Overview:** - An autoimmune disease primarily affecting women. - It involves antibodies attacking acetylcholine receptors on muscle cells. - **Symptoms:** - Weakness that worsens with activity and improves with rest. - Often starts with eye problems like droopy eyelids (ptosis) and double vision (diplopia). - Can affect speech, chewing, swallowing (bulbar muscles). - **Causes:** - Related to thymus gland issues (hyperplasia or thymoma) in some cases. - **Diagnosis:** - Tests include nerve conduction studies and single fiber EMG to assess muscle response. - Decremental response in nerve conduction tests and increased jitter in EMG are common findings. A screenshot of a white text Description automatically generated - **Treatment:** - **Medications:** Acetylcholinesterase inhibitors (like pyridostigmine) increase available acetylcholine at the neuromuscular junction. - **Immunosuppressants:** Used to manage the autoimmune aspect, such as steroids, azathioprine, or methotrexate. - **Other Therapies:** Intravenous immunoglobulin (IVIG) and plasmapheresis can be used in severe cases or crises. - **Surgical Intervention:** Thymectomy (removal of the thymus) may be considered in certain cases, especially if there\'s a thymoma present. \_\_\_\_\_\_Top of Form Which of the following neuromuscular diseases affects the postsynaptic region? - Bottom of Form - Myasthenia gravis (MG) Which of the following is NOT involved in the pathology of myasthenia gravis? - Pupils A 45-year-old man presents to your office with fatigue for the past several weeks. He says he feels great during the early hours of the day but complains he is unable to drive back home from his office because of severe weakness. Which of the following statements is true about his likely condition? - It affects proximal muscles more than distal muscles. Which of the following findings in the chest X-ray of a patient with myasthenia gravis is most relevant in the management? - Thymic shadow