[A case of progressive encephalomyelitis with rigidity and myoclonus associated with anti-GAD, anti-glycine receptor and anti-GM1 antibodies].

A 62-year-old woman with one-year history of type 1 diabetes mellitus was admitted to our hospital with progressive weakness in the lower extremities and urinary dysfunction following high fever. On admission, she had rigidity and myoclonus in the upper extremities with sensory ataxia. Cerebrospinal fluid examination revealed mild pleocytosis and oligoclonal band. Glutamic acid decarboxylase (GAD) antibodies were detected at high titer in serum, but antibodies to glycine receptor (GlyR), thyroid peroxidase, mitochondrial M2, and GM1 were also detected. She was diagnosed with progressive encephalomyelitis with rigidity and myoclonus (PERM), which probably developed on the basis of polyglandular autoimmune syndromes. The clinical symptoms began to improve after initiation of intravenous high-dose methylprednisolone. Muscle weakness might be related to GM1 antibodies. This is the first report of PERM, in which GM1 antibodies were detected with GAD and GlyR antibodies.