Trauma-induced myasthenia gravis: coincidence or causal relationship?

We report a case of a 55-year-old man presenting with diplopia, masticatory weakness and dysarthria several weeks post multitrauma. The clinical suspicion of myasthenia gravis (MG) was supported with positive acetylcholine receptor antibodies and abnormal repetitive stimulation study. He responded well to pyridostigmine, intravenous immunoglobulin and oral prednisolone. In this report, we describe the timing and progression of MG in our patient, and review the literature pertaining to the relationship between trauma and MG. The search for definitive evidence of causation may be impractical, but should not delay the recognition and management of a treatable condition.