Associated factors of the Myasthenia Gravis Activities of Daily Living (MG-ADL) score were investigated in 55 patients who had had generalized MG for more than 5 years. In multivariate analysis, correlates of the MG-ADL score at the last follow-up were the total number of fast-acting treatments (FTs) (standardized regression coefficient 0.617，P < 0.001) and Myasthenia Gravis Foundation of America (MGFA) classification (standardized regression coefficient 0.227，P = 0.032) (F = 32.7，P < 0.001). In patients with a score of 5 or more on MG-ADL at the last follow-up, tendency as follows were seen: 1) early-onset (P = 0.002), 2) longer duration (P = 0.014), 3) high frequency of MGFA classification V (P = 0.017), 4) high frequency of the total number of FTs (P < 0.001), and 5) higher dose of prednisolone at the last follow-up (P = 0.003). MGFA V, early-onset without depending on E-L-T classification, or difficulty of reduction for high doses of prednisolone can be the target of novel treatment for MG, and future prospective study will be expected.

The patient was a 30-year-old man who developed muscle weakness in both lower extremities, sensory deficits below the fourth thoracic spinal cord level, and bladder rectal dysfunction owing to cytomegalovirus (CMV) associated myelitis. His blood tests showed mononucleosis, hepatic dysfunction, and the presence of serum CMV-IgM antibodies, and T₂-weighted imaging on MRI displayed a continuous high signal on the ventral side of the spinal cord. Although his medical history and laboratory tests did not indicate that he was immunocompromised, we speculated he had CMV-associated myelitis. As the first infection with CMV in a non-immunocompromised adult can result in mononucleosis, we considered that this patient developed myelitis after mononucleosis caused by CMV infection for the first time. CMV-associated myelitis in non-immunocompromised individuals is rare. In general, CMV infections are common in immunosuppressed individuals. However, in Japan, adults with CMV antibodies have recently been decreasing, and hence CMV infections in non-immunocompromised adults are expected to increase in the future.

A 57-year-old man presented with headache, transient right upper extremity weakness and numbness one month after recovery from coronavirus disease 2019 (COVID-19). His medical history included Graves’ disease and IgG4-related ophthalmic disease. He had been administered prednisolone. His weakness and numbness were transient and not present on admission. Contrast-enhanced CT and MRI of the head showed thrombi in the superior sagittal sinus, right transverse sinus, sigmoid sinus, and the right internal jugular vein. Digital subtraction angiography showed occlusion at the same sites and mild perfusion delay in the left frontoparietal lobe. We diagnosed the patient with cerebral venous sinus thrombosis and treated him with anticoagulation. The thrombi partially regressed three months later, and perfusion delay became less noticeable. Cerebral venous sinus thrombosis is an important complication of COVID-19. Patients with predisposing factors, including Graves’ disease and IgG4-related ophthalmic disease, may be at increased risk of developing cerebral venous sinus thrombosis even after recovery from COVID-19.

An 82-year-old Japanese woman without underlying disease was admitted to our hospital 3 days after she noticed lower-limb weakness. At presentation, she had lower-leg motor paralysis with mild upper-limb paresis and left Ramsay Hunt syndrome. Cerebrospinal fluid (CSF) findings revealed moderate pleocytosis. A polymerase chain reaction for varicella zoster virus (VZV) DNA in CSF was positive. MRI using 3D Nerve-VIEW (Philips) and contrast T₁ images showed high-intensity lesions on the L2–5 and S1–2 spinal roots. A new subtype of VZV-associated polyradiculoneuritis was diagnosed in this patient. We provide the case details and compare three similar reported cases.

The case was a 53-year-old woman. At birth, she was diagnosed with a false Taussig-Bing anomaly with pulmonary artery stenosis and a single ventricle. However, no cardiac surgery was performed, and conservative treatment was continued by a cardiovascular surgeon even after adulthood. Because of secondary polycythemia and a history of multiple cerebral infarctions, she took anti-platelet drugs and anti-coagulants. However, she was admitted with the diagnosis of cerebral infarction for the fourth time. It was considered that the patient was at high risk of paradoxical cerebral embolism due to cardiac malformation with cyanotic congenital heart disease accompanied by coagulation abnormalities. Considering the pathophysiology, we decided to use aspirin in combination with warfarin.

A 48-year-old Japanese male experienced slowly progressive diplopia. He had no family history and was negative for the edrophonium chloride test. Blood analysis showed elevated lactic acid and pyruvic acid levels, suggesting mitochondrial disease. A muscle biopsy from the biceps brachii was performed, but no pathological or genetical mitochondrial abnormalities were detected. Subsequently, he underwent muscle plication for diplopia in which the right inferior rectus muscle was biopsied. Genetic examination of genomic DNA extracted from the extraocular muscle tissue revealed multiple mitochondrial gene deletions, with a heteroplasmy rate of approximately 35%, resulting in the diagnosis of chronic progressive external ophthalmoplegia. In mitochondrial diseases, the tissue distribution of mitochondria with disease-associated variants in mtDNA should be noted, and it is important to select the affected muscle when performing a biopsy for an accurate diagnosis.