Search

The patient is an 18-year-old female. She had a history of acute disseminated encephalomyelitis at the age of 6 and 7. She visited our hospital due to acute disturbance of consciousness, quadriplegia, and numbness of left upper and lower extremities. Brain MRI showed multiple DWI/FLAIR high-signal lesions in the bilateral cerebral hemispheres, cerebellum, and brainstem. Qualitative test indicated that serum anti-MOG antibodies was positive, and she was diagnosed with anti-MOG antibody-positive polyphasic disseminated encephalomyelitis. Intravenous mPSL pulse therapy was performed twice, but the symptoms worsened. As a second line treatment, plasma exchange was started. However, she developed transfusion related acute lung injury. Alternatively, she was treated with immunoadsorption plasmapheresis. Her symptoms were significantly improved. This case seems to be valuable because there are few reports showing effectiveness of immunoadsorption therapy on anti-MOG antibody-related diseases, especially for polyphasic disseminated encephalomyelitis.

An 84-year-old woman developed blepharoptosis, diplopia, weakness of extremities, and dysphagia with elevation of serum CK levels after treatment with nivolumab against renal cell carcinoma. 3 Hz repetitive stimulation showed waning in the trapezius muscle, leading to the diagnosis of myasthenia gravis. Laboratory examination showed that anti-acetylcholine receptor antibody was negative. We performed IVIg and steroid therapy. However, her symptoms did not improve, and she died of respiratory failure, although serum CK levels ameliorated to the normal range. The results of autopsy showed atrophy of muscle fibers and massive infiltration of inflammatory cells in the endomysium of the iliopsoas muscle and diaphragm, indicating occurrence of myositis. Immunohistochemical analysis showed that CD8-positive T cells mainly infiltrates in the endomysium with a small number of CD4-potive T cells. Here, we report an autopsy case of nivolumab-induced myasthenia gravis and myositis.