Case report: MRI-negative myelitis following COVID-19 with SEP abnormalities: a case series and literature review.

Coronavirus Disease 2019 (COVID-19) is known to have various, neurological manifestations. We herein report three patients with MRI-negative myelitis following COVID-19 with abnormal somatosensory evoked potentials (SEPs). Decreased amplitude of the cortical potential and prolonged latency in the SEPs contributed to diagnosing myelitis in the present patients. The SEP findings improved as the neurological symptoms improved. Despite a delay in initiating immunosuppressive treatment after myelitis onset, all the patients improved clinically. In the light of recent progress in COVID-19 research, several hypotheses can be made to explain the pathophysiology underlying MRI-negative myelitis, including antibody-binding and microglial synapse elimination.

Acute Reversible Encephalopathy with Neuronal Intranuclear Inclusion Disease Diagnosed by a Brain Biopsy: Inferring the Mechanism of Encephalopathy from Radiological and Histological Findings.

A 75-year-old man presented with headache and disturbance of consciousness. Magnetic resonance imaging revealed edema localized mainly in the cortex and linear contrast enhancement. A brain biopsy revealed numerous astrocytes with inclusion, and genetic testing demonstrated prolonged GGC repeats in NOTCH2NLC. The present case provided two novel insights into the mechanism underlying encephalopathy associated with neuronal intranuclear inclusion disease. First, the histological findings at a site with contrast enhancement on magnetic resonance imaging did not demonstrate any organic association, such as the presence of inflammation or ischemic changes. Second, the imaging and cerebrospinal fluid findings demonstrated increased cerebral blood flow and opening of the blood-brain barrier, indicating the cause of the cerebral swelling.

[Case Report: Broca's Aphasia in a Left-Handed Patient with a Right Brain Infarction and Early Stage Aphonia].

We report a case of Broca's aphasia in a left-handed patient with a right brain infarction. The patient's speech is consistent with a particular type of aphemia, that is, without vocalization except for a few phonemes or words. The patient presented with aphonia in an early stage. The lack of speech could be due to the impairment of the phonological-speech process or speech initialization. This type of aphemia has been reported to involve the right inferior precentral gyrus or right middle and inferior frontal gyri. Our patient had both lesions. The symptom and the lesion of this type of aphemia could differ from those of another type of aphemia corresponding to apraxia of speech, and the speech of Broca's aphasia could have multiple mechanisms. Our case shows Alexander's anomalous type with atypical lateralization and distribution of the lesion. Verbal intrahemispheric dissociation apraxia was suspected in our patient. The coexistence of aphasia, anosodiaphoria of hemiplegia is a dual symptom in which bilateral hemispheric functions exist in a unilateral hemisphere. (Received 1 December, 2021; Accepted 1 February, 2022; Published 1 April, 2022).

Association of autoantibodies to muscarinic acetylcholine receptors with gastrointestinal symptoms and disease severity in patients with postural orthostatic tachycardia syndrome.

Previous studies have reported a relationship between postural orthostatic tachycardia syndrome (POTS) and positivity for serum autoantibodies against G-protein-coupled receptors (GPCRs). However, the role of these autoantibodies in POTS is unclear. The present retrospective study analyzed the autoimmune etiology of POTS in 24 patients using a head-up tilt test to assess for any correlation between the clinical features of POTS and serum levels of autoantibodies against diverse GPCRs. In total, ten assessment items, including autonomic function tests, were analyzed. Of these, persistent, gastrointestinal symptoms and disease severity showed a significant association with the serum level of anti-muscarinic acetylcholine receptor (mAChRs) antibodies (gastrointestinal symptoms, M1, M2, M5; disease severity, M1, M3, M4, M5) [P <0.05]), while no significant association was found between the clinical features and autoantibodies against adrenergic receptors (α1, α2, ß1, ß2), angiotensin receptor 1, or endothelin receptor A. The patients were further divided into two groups based on the presence or absence of persistent gastrointestinal symptoms and then were characterized by the ten assessment items and neuropsychological tests, including the Wechsler Adult Intelligence Scale score and Self-Rating Depression Scale score. The results demonstrated a clear difference between the two groups in terms of disease severity, age at onset (older or younger than 20 years), and processing speed index (P <0.05), which were highly consistent with the association between these clinical features and the levels of serum anti-mAChR antibodies, particularly the anti-M5 receptor antibody. These findings suggested that anti-mAChR antibodies may play an important role in a subgroup of POTS patients with persistent gastrointestinal symptoms.

Novel pathogenic VPS13A gene mutations in Japanese patients with chorea-acanthocytosis.

OBJECTIVE: To identify mutations in vacuolar protein sorting 13A (VPS13A) for Japanese patients with suspected chorea-acanthocytosis (ChAc). METHODS: We performed a comprehensive mutation screen, including sequencing and copy number variation (CNV) analysis of the VPS13A gene, and chorein Western blotting of erythrocyte ghosts. As the results of the analysis, 17 patients were molecularly diagnosed with ChAc. In addition, we investigated the distribution of VPS13A gene mutations and clinical symptoms in a total of 39 molecularly diagnosed Japanese patients with ChAc, including 22 previously reported cases. RESULTS: We identified 11 novel pathogenic mutations, including 1 novel CNV. Excluding 5 patients with the unknown symptoms, 97.1% of patients displayed various neuropsychiatric symptoms or forms of cognitive dysfunction during the course of disease. The patients carrying the 2 major mutations representing over half of the mutations, exon 60-61 deletion and exon 37 c.4411C>T (R1471X), were localized in western Japan. CONCLUSIONS: We identified 13 different mutations in VPS13A, including 11 novel mutations, and verified the clinical manifestations in 39 Japanese patients with ChAc.

[A case of encephalitis with hyperfamiliarity for faces].

A 21-year-old right-handed woman was admitted to our hospital with fever, headache, and seizures. On admission, she showed anterograde and retrograde amnesia. These features, together with mild pleocytosis in the cerebrospinal fluid, led to the diagnosis of encephalitis. Brain MRI was normal. EEG revealed small spike waves in the left temporal lobe. There were no recurrent convulsions. Five days later, she stated she had hyperfamiliarity for faces of people she had never met before. She reported that many people appeared familiar regardless of age, sex, and profession; however, feelings of likes and dislikes did not accompany these symptoms. This symptom lasted for 20 days. Her ability to recognize known faces was normal, and prosopagnosia was not present. Neuropsychological tests indicated that her verbal memory was impaired. The retrograde amnesia remained until discharge. Considering the psychological findings attributable to left temporal lobe dysfunction, as well as previous reports on similar cases, our case suggests a possible relationship between lesions of the left temporal lobe and hyperfamiliarity for faces.