Brain and Nerve最新文献

Autoimmune encephalitis presenting with predominant psychiatric symptoms is termed autoimmune psychosis. Identifying clinical features indicative of autoimmune psychosis-referred to as red flags-facilitates early diagnosis. These red flags encompass an infectious prodrome, rapid progression, tumors (currently or recently diagnosed), coexisting autoimmune disorders, severe headache, fluctuating catatonia, involuntary movements, focal neurologic deficits, reduced consciousness, cognitive impairment, autonomic dysfunction, speech impairment, seizures, hyponatremia (unrelated to medication side effects), and malignant syndromes triggered by antipsychotic medications.

Dementia with Lewy bodies (DLB) can lead to pronounced behavioral and psychological symptoms. A 75-year-old woman presented with forgetfulness and visual hallucination, frequently reporting that a man in white clothing appeared and then departed. On one occasion, she knocked on a resident's door in an apartment building, prompting a police call from the occupant. Treatment with donepezil and memantine proved effective; however, the symptoms improved with the initiation of day care. An 80-year-old woman exhibited incoherent speech and developed optical illusions. She occasionally displayed violent behavior at night, asserting that an intruder was present in the home. Two years later, during a nighttime episode, she perceived her husband as a stranger and bit him. The husband contacted the police, resulting in her admission to a psychiatric hospital. Both patients received exclusive care from the neurology department. Referrals to neurologists typically occur when behavioral and psychological symptoms predominate or when families request psychological intervention. Referrals to psychiatry are primarily used to treat parkinsonism. Electroconvulsive therapy is indicated when both symptom types reach severe levels. Neurologists and psychiatrists provide the most effective treatment for Lewy body dementia.

Psychogenic non-epileptic seizures (PNES) are characterized by abnormal movements, sensations, awareness, or cognitive changes that resemble epileptic seizures, but are caused by psychological or psychiatric factors. Although the term "PNES" is currently the most widely used and accepted, other terms, such as "functional seizures" and "dissociative seizures," are employed. According to the Fifth Edition of Diagnostic and Statistical Manual of Mental Disorders, PNES is classified as a functional neurological symptom or conversion disorder. Although the prevalence of PNES is lower than that of epilepsy, it is observed in approximately 10% and 20% of patients in epilepsy outpatient clinics and inpatient epilepsy monitoring units, respectively. Following the diagnosis of PNES, patients often face a significant burden regarding healthcare resource use, including diagnostic testing, use of anti-seizure medications, outpatient visits, and emergency room visits. Accessing appropriate treatments remains challenging. However, evidence supporting effective treatments for PNES, such as cognitive behavioral and neurobehavioral therapies, is steadily increasing.

Drug-induced Parkinsonism (DIP) is a common iatrogenic movement disorder. Its clinical manifestations cannot be distinguished from those of idiopathic Parkinson's disease. Prior exposure to dopamine receptor-blocking agents (DRBA) is required for diagnosis. This article reviews the epidemiology, pathophysiology, clinical features, ancillary testing, and treatment of DIP. Clinicians must always suspect DIP when a patient develops subacute Parkinsonism while taking DRBA. Ancillary testing such as DaT scans is often helpful in identifying prodromal Parkinson's disease. When DIP develops, steps should be taken to discontinue the offending agent or, in the case of antipsychotics, dose reduction or a change to an agent with a lower risk of DIP. L-dopa may be required to control parkinsonism in patients with DIP and prodromal PD.

Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common type of hereditary small-vessel disease causing early onset stroke and dementia. The classic CADASIL phenotype predominantly features ischemic lesions, including lacunar infarcts and white matter lesions notably involving bilateral temporal poles. However, hemorrhagic phenotypes such as intracerebral hemorrhage (ICH) and cerebral microbleeds (CMB) are increasingly being recognized, particularly among East Asian populations, compared to those of European descent, suggesting underlying genetic differences. The East Asian-specific NOTCH3 p.R75P variant shows a higher prevalence of hemorrhagic phenotypes, such as ICH and multiple CMB, typically without temporopolar lesions. Structural and pathological analyses revealed that, unlike conventional CADASIL variants, which produce extensive deposition of NOTCH3 extracellular domains in the vascular walls, the p.R75P variant exhibits reduced aggregation, providing a plausible biological explanation for its unique clinical phenotype. This review highlights the distinctive pro-hemorrhagic phenotype associated with the NOTCH3 p.R75P variant, synthesizing current insights into its genetic, pathological, clinical, and radiological features. Enhanced understanding of this variant will broaden the phenotypic spectrum of CADASIL, emphasizing the need for tailored clinical strategies for susceptible populations.

Functional neurological disorders (FND) are frequently observed in neurological clinics. Recently, the approach to this disorder has shifted from a diagnosis of exclusion to a positive diagnosis using so-called "positive signs," which features various forms of incompatibility. Common risk factors for FND include psychological stressors, which are important for diagnosis. Subtypes of FND are classified according to their symptoms. Four entities-functional seizures, functional movement disorders, persistent perceptual postural dizziness, and functional cognitive disorder-are most recognized by neurologists. These subtypes share similar etiologies and pathophysiologies. Among them, positive signs of functional movement disorders are relatively easy for neurologists to detect. New and effective positive signs, recently reported by Japanese neurologists, should be employed to support a positive diagnosis of FND. Neurologists play a critical role in both the diagnosis and treatment of FND.

Autoimmune encephalitis, within the psychiatric domain, encompasses two concepts involving psychiatric symptoms triggered by cell-membrane surface antibodies: NMDAR encephalitis, which manifests as encephalitis in neurology, and neuronal autoantibodies detected predominantly in the serum of patients with schizophrenia. Autoimmune encephalitis is associated with humoral immunity abnormalities caused by autoantibodies in the acute phase and cell-mediated immunity disruptions, including those in the chronic phase. Follow-up knowledge is required to provide evidence for immunotherapy in patients with mental illnesses.

Dementia with Lewy bodies (DLB) is characterized by a wide variety of symptoms, of which the combinations and order of appearance vary widely between patients. The primary target symptoms for treatment must be identified for each patient to establish a treatment plan. In this article, from a psychiatrist's perspective, I have summarized the symptoms that are targets of treatment, along with the severity of dementia and the key collaboration points between psychiatry and neurology. Attending physicians have experienced difficulties understanding the main treatment needs of their patients and caregivers, despite their expertise in DLB, because of the various clinical manifestations. It is therefore important for clinicians to pay attention to the need to treat psychiatric symptoms, cognitive impairment, Parkinsonism, sleep-related disorders, autonomic dysfunction, and abnormal eating behaviors.

Epilepsy often presents challenges at the intersection of psychiatry and neurology. Diagnosis relies primarily on detailed interviews and electroencephalography tests, with differentiation from other conditions being crucial. Distinguishing epilepsy from syncope or psychogenic non-epileptic seizures requires experience and sound judgment. In psychiatry, special attention must be paid to psychiatric symptoms that co-occur with epilepsy and careful consideration is needed when choosing medications. Additionally, for differentiation from other neurological disorders and management of status epilepticus, close collaboration with neurologists is essential, highlighting the need for an integrated approach between both specialties.

Functional neurological disorders (FND), also termed functional neurological symptom disorders in the DSM-5-TR, are characterized by motor or sensory abnormalities lacking neurological explanation. Historically, this condition has been linked to hysteria. The concept of conversion-a psychological mechanism wherein repressed unconscious conflicts manifest as physical symptoms-remains widely accepted, though its validity has yet to be proven. Consequently, diagnosing FND no longer requires identifying psychological factors. Instead, the diagnosis is established based on positive neurological signs that lack an organic explanation. While the understanding of FND is evolving toward a biopsychosocial model, no standardized biological treatment currently exists, highlighting the necessity for psychosocial assessment and intervention. A comprehensive, individualized assessment of the patient's pathological narrative is preferred, in which traditional interpretations of conversion remain relevant. Cognitive behavioral therapy and psychodynamic therapy have been shown to be effective, yet accessibility remains limited, and patients with FND often exhibit reduced engagement. Even in clinical settings with restricted access to structured psychotherapy, the principles of Pierre Janet and Morita therapy can be effectively applied in treatment. Psychiatry is increasingly acknowledged as pivotal in refining treatment methodologies in clinical practice, with careful attention to the complexities of the mind.