We appreciate Dr Liewluck's comment on our study1 and for suggesting an important neuromuscular symptom in patients with MG. Rippling muscle is characterized by signs of muscular hyperexcitability, which can be induced by muscle stretch or percussion. In addition to the genetic form, rippling muscle is sometimes immune-mediated and observed in patients with MG. Certain types of autoantibodies, including those against striated muscle antigens and neuronal voltage-gated potassium channels (VGKC), are detected in the serum of these patients. We agree that rippling muscle can be an immune-mediated neurological symptom in patients with MG, although the frequency of this symptom in patients with MG is probably very low. However, we believe that rippling muscle is not directly associated with inflammatory myopathy in MG.
Suzuki S, Suzuki N. Immune-Mediated Rippling Muscle Disease: Another Inflammatory Myopathy in Myasthenia Gravis—Reply. Arch Neurol. 2010;67(7):896-897. doi:10.1001/archneurol.2010.125