Predominant Myofibrillar Pathology with Preserved Sarcolemmal Aquaporin 4 Immunoreactivity in a Patient with Neuromyelitis Optica-Associated HyperCKemia

A 49-year-old man developed recurrent myalgia and hyperCKemia during acute attacks of neuromyelitis optica. Muscle biopsy was performed, and the pathological findings were analyzed. Predominant myofibrillar pathology was observed, which constitutes a unique finding that has not been reported before. This case result shows that neuromyelitis optica-associated hyperCKemia can produce variable pathologic phenotypes. Further studies are needed to elucidate the relationship between myofibril destruction and aquaporin 4 autoimmunity.