Encephalitis and meningitis are neurological emergencies in which delayed diagnosis may lead to severe neurological sequelae, necessitating accurate and rapid etiological identification. In recent years, metagenomic next-generation sequencing (mNGS), which enables comprehensive analysis of microbial genomes without prespecified hypotheses, has attracted increasing attention. Its clinical application in neuroinfectious diseases has contributed to improved diagnostic yield and the detection of rare pathogens. In particular, mNGS has been shown to be useful in clinically challenging situations such as culture-negative cases, anaerobic infections, mixed infections, and immunocompromised hosts. However, the technology also has inherent limitations, including enormous data volume, challenges in interpreting pathogenic relevance, limited turnaround time, high cost, and a lack of standardized analytical pipelines. Thus, although mNGS represents a valuable complementary tool to conventional diagnostic methods, it is not universally applicable, and its results must be carefully interpreted within appropriate clinical contexts.

With the advancement of genetic medicine, opportunities to perform genetic testing in neurology practice are increasing. To address this trend, we conducted a survey on the involvement of neurologists in genetic medicine. A total of 658 respondents (9.6%) participated, and 94.4% reported experience in performing genetic testing. The increased opportunity to perform genetic testing was attributed to the recent emergence of disease-modifying therapies, which are beneficial for the early diagnosis and treatment of patients, as well as the growing need to consider reproductive options such as prenatal testing and preimplantation genetic testing for monogenic disorders. Educational opportunities aimed at improving the genetic medicine skills of all neurologists are urgently needed.

Background: Sleep–wake problems and sleep-related disorders, which are common attributes of neurological diseases, often remain under-recognized and under-treated. Insufficient education in sleep medicine might contribute to this gap. Methods: The Sleep Medicine Section of the Japanese Society of Neurology conducted a nationwide, web-based survey of its full-member physicians (N = 9,703), assessing neurologists’ education, clinical practice, and interest in sleep medicine. Results: Of the 904 survey participants, only 10% considered their undergraduate education on sleep–wake problems and sleep-related disorders as adequate, whereas 86% rated it as insufficient. Furthermore, nearly 90% of the participants recognized the importance of these education gaps in neurological practice, and more than 90% expressed a desire for further education. Regarding clinical management, fewer than 5% felt confident and 15% expressed anxiety or a tendency to avoid such cases. Approximately 87% reported encountering such problems and disorders in clinical practice, and 47% reported managing them at least weekly. Insomnia, circadian rhythm sleep–wake disorders, and hypersomnia were considered the most difficult to treat. Respondents showed strong interest in lectures and on-demand webinars on rapid eye movement sleep behavior disorder (71.1%), restless legs syndrome (62.3%), and the relationship between sleep–wake problems or sleep-related disorders and neurodegenerative diseases (77.1%) or dementia (68.3%). Conclusions: Although the importance of sleep–wake problems and sleep-related disorders and additional educational opportunities are well-recognized, confidence in diagnosis and treatment remained low. This survey revealed an unmet clinical need in sleep medicine among Japanese neurologists, underscoring the importance of structured, accessible education at undergraduate and postgraduate levels.

Domestic studies examining word fluency tasks in patients with Parkinson’s disease (PD) are limited. This study compared quantitative and qualitative features of a word fluency task included in the Japanese version of the Montreal Cognitive Assessment (MoCA-J) between patients with PD and patients attending a memory clinic. We retrospectively analyzed the MoCA-J word fluency task requiring the generation of words beginning with the Japanese syllable “ka” in 100 patients with PD and 100 memory clinic patients. The number of recalled words and linguistic characteristics of the responses were evaluated. Cognitive function was assessed using the Mini-Mental State Examination (MMSE) and MoCA-J. The mean MMSE scores were higher in the PD group than in the memory clinic group (27.6 vs. 24.4), as were MoCA-J scores (23.5 vs. 18.7). The mean number of recalled words did not differ between groups (PD: 9.1; memory clinic: 9.2) and showed positive correlations with cognitive scores. The PD group produced 318 unique words, whereas the memory clinic group produced 285. The proportion of adjectives was lower in the PD group. No significant between-group differences were observed in semantic category classifications, including object names, motion-related words, and emotion/state-related words. Although global cognitive function was relatively preserved in patients with PD, their word fluency performance was comparable to that of memory clinic patients, with subtle differences in linguistic characteristics.

A 68-year-old man presented with numbness and pain of the hands. Neurological examination revealed distal limb weakness, diminished tendon reflexes, sensory disturbances in all extremities, tremors, ataxia, and orthostatic hypotension, which caused repeated fainting spells and falls. The nerve conduction studies revealed definite demyelinating abnormalities. The cerebrospinal fluid protein levels were markedly increased at 638 mg/dl. The contrast-enhanced MRI neurography revealed nerve root enlargement and enhancement, and the 123I-metaiodobenzylguanidine myocardial scintigraphy revealed abnormalities, indicating postganglionic sympathetic small fiber disturbance. This patient was initially diagnosed with a distal acquired demyelinating symmetric type of chronic idiopathic demyelinating polyradiculoneuropathy (CIDP). Intravenous immunoglobulin (IVIg) therapy was nearly ineffective, which was different from typical CIDP, and corticosteroids demonstrated mild efficacy. Five years after his initial visit, anti-neurofascin-155 (NF155) autoimmune nodopathy was suspected based on his pathognomonic symptoms, examination results, and ineffectiveness of IVIg. Anti-NF155-IgG4 antibodies were negative; however, anti-NF155-IgG antibodies tested positive, leading to a final diagnosis of anti-NF155 antibody-positive autoimmune nodopathy. This case highlights the clinical significance of non-IgG4 class anti-NF155-IgG antibodies and the involvement of postganglionic sympathetic small fibers in anti-NF155-IgG-related autoimmune nodopathy.

A 53-year-old woman presented with chronic anorexia and gait disturbance. During evaluation at another hospital, brain MRI revealed abnormal high signal intensities in both supratentorial and infratentorial regions, prompting referral and admission to our hospital. On admission, she exhibited non-lateralized hypertension, decreased responsiveness, hypophonia, masked face, bradykinesia, shuffling gait, and hyperreflexia. Blood tests showed mild inflammatory markers. Based on her hypertension and MRI findings, posterior reversible encephalopathy syndrome (PRES) was diagnosed, and antihypertensive therapy was initiated. Her symptoms and imaging findings improved, though some abnormalities persisted. During further evaluation for the cause of hypertension, she contracted COVID-19. Despite recovery, low-grade fever and inflammatory response persisted. Contrast-enhanced CT revealed perivascular enhancement around the aortic arch branches, leading to a diagnosis of Takayasu arteritis. This case highlights PRES as a clinical trigger for the diagnosis of Takayasu arteritis.

Opsoclonus-myoclonus syndrome (OMS), characterized by symptoms including rapid eye movements, myoclonus, and cerebellar ataxia, is one of the paraneoplastic neurological syndrome. A 68-year-old woman was admitted with oscillopsia, dizziness, and gait disturbance caused by postural tremor. Clinical evaluation led to a diagnosis of Kelch-like protein 11 (KLHL11)-associated paraneoplastic OMS, secondary to small cell lung cancer (cT1cN3M1a, stage 4A). In most cases, the improvement of the neurological symptoms is limited unless the underlying malignancy is effectively treated. Therefore, cancer therapy in combination with immunotherapy is essential, even in patients with poor performance status. Here, we report a case in which both immunotherapy and cancer treatment led to improvement in neurological symptoms associated with KLHL11-related paraneoplastic OMS.

For young doctors and students, presenting a case at a regional meeting may be the first step in their academic careers. Such presentations require appropriate case selection, a satisfactory literature search, discussion with a mentor, writing an abstract, making slides, and providing an effective response to the audience’s questions. The sequential process from case experience to presentation provides a valuable learning experience for young physicians and students and enhances their clinical abilities. On the day of the meeting, presenters should ensure that the presentation stays strictly within the allotted time and speak without reading from a prepared script. A good presentation requires (i) simple and understandable slides, (ii) a clear “learning point” for the audience, and (iii) effective spoken delivery.