Characterization of skeletal muscle antibodies in patients with Autoimmune rippling muscles and Myasthenia Gravis, by Thomas C. Watkins.

Abstract

Rippling muscle disease has been previously described by Torbergsen, as a rare autosomal dominant condition characterized by: muscle stiffness after resting, localized mounding ofmuscle after resting and electrically silent wave like contractions after stretching (Le. rippling muscles). In 1990 Ansevin described a patient displaying electrically silent rippling muscles with no evidence ofMyasthenia gravis. In 1995 the patient returned for treatment for myasthenia gravis (MG). At the time oftreatment for MG the rippling muscles were absent. It was theorized that the rippling muscles, in this patient, were the result of an autoimmune condition related to the one that brought on the MG. We have examined serum obtained from this patient with active rippling symptoms and when the rippling symptoms had abated, by western blotting. We have also examined serum obtained from two other patients with rippling muscles and MG. Results indicate that high and intermediate molecular weight antigens in skeletal muscle are recognized by autoantibodies in patients with rippling muscles, which are not present in patients with myasthenia gravis alone. The data suggest autoantibodies may be binding to stretch activated channel proteins causing the symptoms of rippling muscle.