Neurology in Japan did not develop from the separation of neuropsychiatry into neurology and psychiatry, which casts a shadow on the present situation of Japanese neurology. Functional neurological disorder (FND; hysteria) is a typical link between neurology and psychiatry. FND is a common disorder, which has been described from the ancient times and has also been the headstream of neurology. FND is not diagnosed by exclusion or by psychiatric causes, but should be actively diagnosed based on the neurological signs themselves (= positive signs of FND) as early as possible, with minimal ancillary tests. This opinion has been supported by the newest Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5). Many positive signs have been described. Assessment by a neurologist also becomes a treatment.

The post-vaccination antibody response in patients with immune-mediated neuromuscular diseases under immuno-suppressive therapy has not been sufficiently verified. The Japanese Society of Neurology has stated that coronavirus disease 2019 (COVID-19) vaccination should be given priority in patients with immunotherapy-associated neuromuscular diseases; however, data on antibody production to a novel mRNA vaccine are scarce in these patients. In this study, we aimed to measure residual antibody titers after the second dose and produced antibodies after the third dose of SARS-CoV-2 mRNA vaccine in 25 patients with neuromuscular diseases under immuno-suppressive therapy (disease group). We compared the disease group antibody titers with those of 829 healthy employees in our hospital (control group). The disease group included 17 patients with myasthenia gravis, 4 with multiple sclerosis, 3 with inflammatory muscle disease, and 1 with chronic inflammatory demyelinating polyneuropathies. Seven cases of the disease group showed negative antibody levels (<15.0 s/co) before the third vaccination, and antibody titers in the positive cases ranged from 16.9 to 4,589.0 s/co. Three of the seven antibody-negative cases turned positive after the third vaccination, and all but one of the antibody-positive cases showed a booster effect, with antibody titers after the third dose ranging from 245.1 to 85,374.0 s/co (1.0 to 885.0 times higher than those before vaccination). Although the immune response in the disease group was modest compared to the control group, in which antibody titers after the third vaccination ranged from 67.8 to 150,000 s/co (0.9 to 5,402.1 times higher than those before vaccination), the result indicated that a constant immune response was achieved under immuno-suppressive therapy. Even in the control group, three participants tested negative for residual antibody before the third inoculation, and four of the antibody-positive participants (27.7–24,054.0 s/co) lacked a booster effect after the third vaccination.

The patient was a 44-year-old man who developed cognitive impairment beginning at the age of 35 years that gradually worsened. The cognitive impairment led to a difficult social life, and he retired from his company. After hospitalization and workup, he was diagnosed with primary progressive multiple sclerosis (PPMS) that presented only with cognitive impairment for 10 years. Since he had multiple predictive factors for poor prognosis, anti-CD20 monoclonal antibody therapy was implemented. Cognitive impairment and cerebral blood flow SPECT findings improved, and he returned to a social life 3 months later. Anti-CD20 monoclonal antibody therapy was effective in improving cognitive impairment in a case of an advanced stage of PPMS.

Sjögren’‍s syndrome (SJS) is a common autoimmune disease. Generally, posterior reversible encephalopathy syndrome (PRES) is often concomitant with autoimmune disease; however, PRES rarely complicates SJS. Thus, the detailed clinical course of cases with SJS and PRES remains unknown. We present the case of a 71-year-old female patient with primary SJS, whose magnetic resonance (MR) images showed bilateral vasogenic edema in the basal ganglia, brainstem, and cerebellum. Cerebrospinal fluid (CSF) examination revealed increased IgG index and higher interleukin-6 and anti-SSA-autoantibody levels. Management of her blood pressure combined with corticosteroid therapy improved her neurological symptoms, including abnormal CSF and MR imaging findings.