Life-threatening misdiagnosis of bulbar onset myasthenia gravis as a motor neuron disease: How much can one rely on exaggerated deep tendon reflexes


Department of Neurology, Isfahan Neurosciences Research Center, Alzahra Hospital, Isfahan University of Medical Sciences, Isfahan, Iran


The autoimmune disease myasthenia gravis (MG), can mimic a variety of neurological disorders leading to a delay in diagnosis and treatment. On occasions, misdiagnosis of MG could lead to unnecessary therapeutic interventions. We report the case of a 50 year-old man, in whom MG was mistaken for motor neuron disease (MND). Subsequently, correct diagnosis and optimal management resulted in saving his life and significant improvement in his functional status. We discuss the importance of considering MG as one of the potential differential diagnoses among cases of new onset or recurrent unexplained bulbar symptoms, despite exaggerated deep tendon reflexes. Also, a literature review on the misdiagnosis of MG and the potential pitfalls in MG diagnosis are discussed.


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