2018 Volume 57 Issue 20 Pages 3021-3024
An 82-year-old woman developed neck weakness and dysarthria with antibodies against acetylcholine receptor (AChR) and low-density lipoprotein receptor-related protein 4 (LRP4). Myasthenia gravis (MG) was diagnosed by edrophonium and repetitive nerve stimulation tests. Her symptoms resolved completely by immunotherapy. One year later, she presented with muscle weakness and bulbar palsy accompanied by atrophy and fasciculation. Her tendon reflexes were brisk, and Babinski's sign was positive. She was diagnosed with probable amyotrophic lateral sclerosis (ALS). Immunotherapy did not improve her symptoms, and she ultimately died of respiratory failure. MG and ALS may share a pathophysiology, including anti-LRP4 antibodies at the neuromuscular junction.