Thymoma-associated Progressive Encephalomyelitis with Rigidity and Myoclonus (PERM) with Myasthenia Gravis.

We report a case of a 72-year-old woman who initially presented with symptoms of bulbar myasthenia and was positive for anti-acetylcholine receptor antibodies. She subsequently developed painful muscle spasms, myoclonus, and stiffness. Thymoma was detected, and both anti-glycine receptor and anti-glutamic acid decarboxylase antibodies were found. She was diagnosed with thymoma-associated progressive encephalomyelitis with rigidity and myoclonus (PERM). She experienced marked improvement after thymectomy followed by plasma exchange and intravenous immunoglobulin and prednisolone. This case suggests that thymectomy followed by sufficient immunosuppression may be useful in the treatment of thymoma-associated PERM. Myasthenia gravis may develop in thymoma-associated PERM patients.

Natalizumab is Effective for the Treatment of Relapsing-remitting Tumefactive Multiple Sclerosis.

We herein report the case of a 57-year-old woman presenting with a biopsy-proven tumefactive demyelinating lesion as her first clinical event. Subsequently, she displayed a relapsing-remitting course with recurrence of large demyelinating lesions exceeding 2 cm in diameter rather than the small ovoid lesions characteristic of multiple sclerosis. Administration of interferon beta did not suppress the disease activity. Finally, treatment with natalizumab, which is a humanized monoclonal antibody against the cell-adhesion molecule α4-integrin, was initiated, resulting in clinical and radiological stabilization. Our experience here suggests that natalizumab may be an effective therapeutic option for relapsing-remitting tumefactive multiple sclerosis with high disease activity.