Abstract

Introduction: Myasthenia gravis (MG) is an autoimmune disorder in which signal transmission in the neuromuscular junction is impaired by antibodies to acetylcholine receptors in the post-synaptic membrane.

Case Presentation: An 84-year-old male was seen in the Emergency room complaining of fever, productive cough and shortness of breath. Community-acquired pneumonia (CAP) was diagnosed and treated with fluids and antibiotics; however, the patient’s shortness of breath did not improve, and a few hours later he developed an acute desaturation. A CT scan of the chest excluded pulmonary embolism but was positive for the presence of a thymoma. Myasthenia gravis was confirmed after detailed history taking, and the patient was started on plasmapheresis along with oral steroids and azathioprine.

Conclusion: Respiratory failure secondary to pneumonia is an atypical manifestation that could be detected in patients affected by myasthenia gravis. Diagnosis of myasthenia gravis can be confirmed with history and physical exam, even with negative panels of acetylcholine receptor antibodies.

Keywords: Myasthenia Gravis; Community Acquired Pneumonia; Respiratory Failure; Thymic Hyperplasia; Thymectomy

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