Podcast # 437 : Myasthenia Gravis

Author: Gretchen Hinson, MD

Educational Pearls:

• Myasthenia gravis (MG) is an antibody mediated autoimmune disorder against the acetylcholine receptors at the neuromuscular junctions.
• Bimodal age distribution (20's-30's: women; 60's-70's: men)
• Presents with fluctuating muscle weakness typically worse at the end of the day with upper extremities affected more than lower and typically involving facial muscles.
• Myasthenia crisis occurs when muscle fatigue begins to cause respiratory depression
• MG was historically diagnosed with the Tensilon test but now often by EMG
• Treatment of MG crisis involves plasma exchange and IVIG. Those in crisis often require intubation and ICU admission

References:

Gilhus NE. Myasthenia Gravis. N Engl J Med. 2016 Dec 29;375(26):2570-2581. doi: 10.1056/NEJMra1602678. Review. PubMed PMID: 28029925.

Roper J, Fleming ME, Long B, Koyfman A. Myasthenia Gravis and Crisis: Evaluation and Management in the Emergency Department. J Emerg Med. 2017 Dec;53(6):843-853. doi: 10.1016/j.jemermed.2017.06.009. Epub 2017 Sep 12. PubMed PMID: 28916122.

Summarized by Travis Barlock, MS4 | Edited by Erik Verzemnieks, MD