Autoimmune Encephalitis and Paraneoplastic Neurological Syndromes with Progressive Supranuclear Palsy-like Manifestations.

BACKGROUND: Advances in diagnostic procedures have led to an increasing rate of diagnosis of autoimmune encephalitis or paraneoplastic neurological syndrome (AE/PNS) among patients with progressive supranuclear palsy (PSP)-like manifestations. METHODS: In this narrative review, we first discuss the clinical characteristics of AE/PNS in comparison to those of PSP, followed by a discussion of diagnosis and treatment. RESULTS: The antibodies involved in these conditions include anti-IgLON5, -Ma2, and -Ri antibodies, each of which has a characteristic clinical presentation. The steps in the diagnosis of AE/PNS in patients with PSP-like manifestations include (i) suspicion of AE/PNS based on clinical presentations atypical of PSP and (ii) antibody detection measures. Methods used to identify antibodies include a combination of tissue-based assays and confirmatory tests. The primary confirmatory tests include cell-based assays and immunoblotting. Treatments can be divided into immunotherapy and tumor therapies, the former of which includes acute and maintenance therapies. CONCLUSIONS: One of the major challenges of diagnosis is that existing reports on PSP-like patients with AE/PNS include only case reports, with the majority discussing antibodies other than anti-IgLON5 antibody. As such, more patients need to be evaluated to establish the relationship between antibodies and PSP-like manifestations.

Functional evaluation of novel variants of B4GALNT1 in a patient with hereditary spastic paraplegia and the general population.

Hereditary spastic paraplegia (HSP) is a heterogeneous group of neurological disorders that are characterized by progressive spasticity and weakness in the lower limbs. SPG26 is a complicated form of HSP, which includes not only weakness in the lower limbs, but also cognitive impairment, developmental delay, cerebellar ataxia, dysarthria, and peripheral neuropathy, and is caused by biallelic mutations in the B4GALNT1 (beta-1,4-N-acetylgalactosaminyltransferase 1) gene. The B4GALNT1 gene encodes ganglioside GM2/GD2 synthase (GM2S), which catalyzes the transfer of N-acetylgalactosamine to lactosylceramide, GM3, and GD3 to generate GA2, GM2, and GD2, respectively. The present study attempted to characterize a novel B4GALNT1 variant (NM_001478.5:c.937G>A p.Asp313Asn) detected in a patient with progressive multi-system neurodegeneration as well as deleterious variants found in the general population in Japan. Peripheral blood T cells from our patient lacked the ability for activation-induced ganglioside expression assessed by cell surface cholera toxin binding. Structural predictions suggested that the amino acid substitution, p.Asp313Asn, impaired binding to the donor substrate UDP-GalNAc. An in vitro enzyme assay demonstrated that the variant protein did not exhibit GM2S activity, leading to the diagnosis of HSP26. This is the first case diagnosed with SPG26 in Japan. We then extracted 10 novel missense variants of B4GALNT1 from the whole-genome reference panel jMorp (8.3KJPN) of the Tohoku medical megabank organization, which were predicted to be deleterious by Polyphen-2 and SIFT programs. We performed a functional evaluation of these variants and demonstrated that many showed perturbed subcellular localization. Five of these variants exhibited no or significantly decreased GM2S activity with less than 10% activity of the wild-type protein, indicating that they are carrier variants for HSP26. These results provide the basis for molecular analyses of B4GALNT1 variants present in the Japanese population and will help improve the molecular diagnosis of patients suspected of having HSP.

[Paraneoplastic Disorders of Peripheral Nervous System].

Paraneoplastic disorders of the peripheral nervous system are immune-mediated neurological syndromes associated with tumors. Several clinical phenotypes have been associated with these disorders. Sensory neuronopathy is the most well-known clinical phenotype, and is caused by neuronal cell injury to the dorsal root ganglia. Symptoms of the peripheral nervous system usually lead to the discovery of tumors. Antineuronal antibodies are occasionally identified in the serum and/or cerebrospinal fluid of these patients. The prevalence of small-cell lung cancer is notable in these patients. Early tumor resection, coupled with the initiation of immunotherapy, may prove effective in improving and stabilizing clinical symptoms.

Case report: Atypical case of autoimmune glial fibrillary acidic protein astrocytopathy following COVID-19 vaccination refractory to immunosuppressive treatments.

A 54-year-old Japanese man presented with headache and fever the day after SARS-CoV-2 vaccination. He became deeply unconscious within a week. Brain MRI showed periventricular linear enhancements and a few spotty lesions in the cerebral white matter. Cerebrospinal fluid (CSF) testing showed mild pleocytosis. He was treated with intravenous methylprednisolone and plasma exchange. However, the white matter lesions enlarged to involve the brainstem and cerebellum, and long cord spinal lesions appeared. Anti-glial fibrillary acidic protein (GFAP) antibody was positive in the CSF and serum, and he was therefore diagnosed as autoimmune GFAP-astrocytopathy (GFAP-A). In addition, high-dose immunoglobulin therapy was administered twice, but his symptoms did not improve; the white matter lesions enlarged further, and modified Rankin Scale score increased to 5. A brain biopsy specimen showed infiltration of macrophages and CD4 + lymphocytes together with neuron and oligodendrocytic injuries and glial scar. Although GFAP-A generally responds well to steroids, the present case developed GFAP-A following SARS-CoV-2 vaccination, with refractory to intensive immunosuppressive therapy and atypical pathologic findings of infiltration of CD4 + lymphocytes and demyelination.

[Clinical features and effects of shunt surgery in patients with progressive supranuclear palsy and idiopathic normal pressure hydrocephalus].

This study aimed to retrospectively review the frequency and clinical features of 13 patients with progressive supranuclear palsy (PSP) and idiopathic normal pressure hydrocephalus (iNPH). All patients were found to have PSP-Richardson's syndrome (PSP-RS). Shunt surgery was effective in 5 of 11 patients (45.5%). A comparison of these 5 patients who responded to shunt surgery versus the remaining 6 patients revealed a significant difference in the reduction of frontal lobe blood flow on cerebral perfusion single-photon emission computed tomography (SPECT) (P = 0.018). These results suggest that PSP-RS is common in patients with PSP and iNPH and indicate the usefulness of cerebral perfusion SPECT in estimating the effect of shunt surgery.

Balamuthia mandrillaris amoebic encephalitis mimicking tuberculous meningitis.

A 76-year-old female with no apparent immunosuppressive conditions and no history of exposure to freshwater and international travel presented with headache and nausea 3 weeks before the presentation. On admission, her consciousness was E4V4V6. Cerebrospinal fluid analysis showed pleocytosis with mononuclear cell predominance, elevated protein, and decreased glucose. Despite antibiotic and antiviral therapy, her consciousness and neck stiffness gradually worsened, right eye-movement restriction appeared, and the right direct light reflex became absent. Brain magnetic resonance imaging revealed hydrocephalus in the inferior horn of the left lateral ventricle and meningeal enhancement around the brainstem and cerebellum. Tuberculous meningitis was suspected, and pyrazinamide, ethambutol, rifampicin, isoniazid, and dexamethasone were started. In addition, endoscopic biopsy was performed from the white matter around the inferior horn of the left lateral ventricle to exclude brain tumor. A brain biopsy specimen revealed eosinophilic round cytoplasm with vacuoles around blood vessels, and we diagnosed with amoebic encephalitis. We started azithromycin, flucytosine, rifampicin, and fluconazole, but her symptoms did not improve. She died 42 days after admission. In autopsy, the brain had not retained its structure due to autolysis. Hematoxylin and eosin staining of her brain biopsy specimen showed numerous amoebic cysts in the perivascular brain tissue. Analysis of the 16S ribosomal RNA region of amoebas from brain biopsy and autopsy specimens revealed a sequence consistent with Balamuthia mandrillaris. Amoebic meningoencephalitis can present with features characteristic of tuberculous meningitis, such as cranial nerve palsies, hydrocephalus, and basal meningeal enhancement. Difficulties in diagnosing amoebic meningoencephalitis are attributed to the following factors: (1) excluding tuberculous meningitis by microbial testing is difficult, (2) amoebic meningoencephalitis has low incidence and can occur without obvious exposure history, (3) invasive brain biopsy is essential in diagnosing amoebic meningoencephalitis. We should recognize the possibility of amoebic meningoencephalitis when evidence of tuberculosis meningitis cannot be demonstrated.

Anti-N-methyl-d-aspartate receptor encephalitis preceded by meningitis lasting up to 60 days.

Long-lasting meningitis complicated by N-methyl-d-aspartate receptor (NMDAR) encephalitis has not been discussed widely in the literature. Herein, we present two cases of anti-NMDAR encephalitis preceded by meningitis. The patients had 60- and 22-day periods of preceding meningitis, which improved with intravenous methylprednisolone and plasmapheresis. No tumors were detected in either of the patients. Although meningitis preceding anti-NMDAR encephalitis is not rare, our patients, especially those who had it for a duration of 60 days, had longer durations of meningitis. This manuscript foregrounds that anti-NMDAR encephalitis might be included in the differential diagnosis of long-lasting meningitis.

[Autoimmune encephalitis and paraneoplastic neurological syndromes presenting atypical parkinsonism: a scoping review].

Recent studies have demonstrated that atypical parkinsonism can be presented in autoimmune encephalitis and paraneoplastic neurological syndromes. However, it is unclear which anti-neural antibodies are involved and when these diseases should be suspected. To address these clinical questions, we conducted a scoping review and analyzed 38 articles. The literature shows that many anti-neural antibodies, including unknown ones, have been reported in progressive supranuclear palsy, corticobasal syndrome, and multiple system atrophy. Moreover, the following symptoms and signs suggest the possibility of autoimmune encephalitis and paraneoplastic neurological syndromes: early onset, acute or subacute progression, the presence of a neoplasm, significant weight loss, abnormal cerebrospinal fluid findings, the absence of typical brain magnetic resonance imaging findings, and the existence of atypical physical examination signs.

Oxygen-Glucose Deprived Peripheral Blood Mononuclear Cells Protect Against Ischemic Stroke.

Stroke is the leading cause of severe long-term disability. Cell therapy has recently emerged as an approach to facilitate functional recovery in stroke. Although administration of peripheral blood mononuclear cells preconditioned by oxygen-glucose deprivation (OGD-PBMCs) has been shown to be a therapeutic strategy for ischemic stroke, the recovery mechanisms remain largely unknown. We hypothesised that cell-cell communications within PBMCs and between PBMCs and resident cells are necessary for a polarising protective phenotype. Here, we investigated the therapeutic mechanisms underlying the effects of OGD-PBMCs through the secretome. We compared levels of transcriptomes, cytokines, and exosomal microRNA in human PBMCs by RNA sequences, Luminex assay, flow cytometric analysis, and western blotting under normoxic and OGD conditions. We also performed microscopic analyses to assess the identification of remodelling factor-positive cells and evaluate angiogenesis, axonal outgrowth, and functional recovery by blinded examination by administration of OGD-PBMCs after ischemic stroke in Sprague-Dawley rats. We found that the therapeutic potential of OGD-PBMCs was mediated by a polarised protective state through decreased levels of exosomal miR-155-5p, and upregulation of vascular endothelial growth factor and a pluripotent stem cell marker stage-specific embryonic antigen-3 through the hypoxia-inducible factor-1α axis. After administration of OGD-PBMCs, microenvironment changes in resident microglia by the secretome promoted angiogenesis and axonal outgrowth, resulting in functional recovery after cerebral ischemia. Our findings revealed the mechanisms underlying the refinement of the neurovascular unit by secretome-mediated cell-cell communications through reduction of miR-155-5p from OGD-PBMCs, highlighting the therapeutic potential carrier of this approach against ischemic stroke.

Autoimmune glial fibrillary acidic protein astrocytopathy associated with breast cancer: a case report.

BACKGROUND: Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy (GFAP-A) is an autoimmune inflammatory central nervous system disorder characterized by the detection of autoantibodies that recognize GFAP in CSF. The pathogenesis of GFAP-A is poorly understood. Some patients had a neoplasm detected and GFAP expressed by neoplasms is plausible as immunogen triggering paraneoplastic neurological autoimmunity. CASE PRESENTATION: We report a case of 76-year-old female patient with GFAP-A complicated with breast cancer. She presented with altered consciousness, nuchal rigidity, speech disturbances, and weakness. Her clinical symptoms were improved by immunotherapy and cancer treatments. Immunohistochemical analysis showed that the restricted tumor expressed GFAP. The infiltration of CD3 + T cells were observed in the peritumoral and intratumoral areas. The most common infiltrating lymphocytes were CD8 + T cells. CD4 + T cells and CD20 + B cells were also observed in the predominant peritumoral area. CONCLUSIONS: These results suggest that GFAP-A may occur in a paraneoplastic neurological syndrome associated with breast cancer.

Neuro-COVID-19.

Neuromuscular manifestations of new coronavirus disease 2019 (COVID-19) infection are frequent, and include dizziness, headache, myopathy, and olfactory and gustatory disturbances. Patients with acute central nervous system disorders, such as delirium, impaired consciousness, stroke and convulsive seizures, have a high mortality rate. The encephalitis/encephalopathy that causes consciousness disturbance and seizures can be classified into three conditions, including direct infection with the SARS-CoV-2 virus, encephalopathy caused by central nervous system damage secondary to systemic hypercytokinemia (cytokine storm) and autoimmune-mediated encephalitis that occurs after infection. The sequelae, called post-acute COVID-19 syndrome or long COVID, include neuromuscular manifestations, such as anxiety, depression, sleep disturbance, muscle weakness, brain fog and cognitive impairment. It is desirable to establish diagnostic criteria and treatment for these symptoms. Vaccine-induced thrombotic thrombocytopenia, Guillain-Barré syndrome, bilateral facial paralysis, encephalitis and opsoclonus-myoclonus syndrome have been reported as adverse reactions after the COVID-19 vaccine, although these are rare.

The Usefulness of Swallowing Pressure Assessment in the Identification of Mild Pharyngeal Weakness of Myasthenia Gravis: A Case Report.

Despite the clinical impact of dysphagia in myasthenia gravis (MG), a standard protocol for diagnosing dysphagia reliably has not yet been established. High-resolution manometry (HRM) provides precise information on pharyngeal pressure. We hypothesized that swallowing pressure assessment using HRM during the edrophonium chloride (EC) test could identify mild bulbar symptoms with no abnormalities on videoendoscopic (VE) and videofluorographic (VF) examination of swallowing, and we tested this hypothesis on a 72-year-old female patient diagnosed with ocular MG who developed slight pharyngeal discomfort over 3 months. The patient's ocular symptoms were stable with pyridostigmine medication. VE and VF revealed no abnormalities. The swallowing pressure along the pharynx was measured using HRM during the EC test. HRM parameters, including velopharyngeal contractile integral and meso-hypopharyngeal contractile integral, were evaluated. These parameters were assessed for three swallows using 3 mL of water. After EC injection, the values of the velopharyngeal contractile integral (78.0 ± 5.4 vs. 134.7 ± 1.3 mm Hg cm·s) and the meso-hypopharyngeal contractile integral were both higher (130.6 ± 1.5 vs. 284.2 ± 11.9 mm Hg cm·s) than those observed before EC injection. Chest computed tomography revealed a thymoma that had not been observed in previous examinations. The patient was diagnosed with thymoma-associated MG. Intravenous immunoglobulin therapy improved the mild dysphagia. We concluded that swallowing pressure assessment during the EC test may be helpful in identifying mild bulbar symptoms in patients with MG.

Autoimmune glial fibrillary acidic protein astrocytopathy resembling isolated central nervous system lymphomatoid granulomatosis.

We report two patients with meningoencephalomyelitis without evidence of extra central nervous system (CNS) involvement. Brain MRI showed linear perivascular radial gadolinium enhancement patterns and spinal cord MRI showed longitudinal extensive T2-hyperintensity lesions. Pathological findings from brain biopsies were angiocentric T-cell predominant lymphoid infiltrates that lacked Epstein-Barr virus-positive atypical B cells. The patients were initially suspected to have isolated CNS-lymphomatoid granulomatosis (LYG). Thereafter, glial fibrillary acidic protein (GFAP)-immunoglobulin G were detected in their cerebrospinal fluid. This finding suggested autoimmune GFAP astrocytopathy. We speculate there is a link between isolated CNS-LYG and autoimmune GFAP astrocytopathy.

[Longitudinally Extensive Transverse Myelitis Caused by Granulomatous Primary Central Nervous System Vasculitis with Characteristic Brain Magnetic Resonance Image: A Case Report].

We report a case of primary central nervous system vasculitis (PCNSV) with longitudinally extensive transverse myelitis. A 47-year-old woman presented with malaise, progressive cognitive impairment, and lower limb spasticity. Diffuse hyperintense areas in the deep cerebral white matter on the diffusion-weighted image and T2-weighted images were observed during brain magnetic resonance imaging. Gadolinium-enhanced T1-weighted images showed multiple linear enhancements. A sagittal T2-weighted image displayed a longitudinal extensive lesion of transverse myelitis in the spinal column from the upper cervical (C7) to the thoracic region (Th12). On brain biopsy, the patient was diagnosed as having granulomatous primary angiitis of the central nervous system (PCNSV). This case suggests that PCNSV could show longitudinally extensive transverse myelitis. (Received 14 January, 2021; Accepted 18 February, 2021; Published 1 August, 2021).

[Differentiating Between HTLV-1 Associated Myelopathy and Amyotrophic Lateral Sclerosis: A Case Report].

We present the case of a 72-year-old woman with slowly progressive spastic paraplegia and painful muscle spasms of the lower limbs. Spastic paraplegia began in the left lower extremity and extended to the right lower extremity 4 months later. We considered the diagnosis of amyotrophic lateral sclerosis (ALS) because of the left-dominant spastic paraplegia of bilateral lower limbs and due to the presence of fasciculation, hyperreflexias, and pathological reflexes. However, cerebrospinal fluid (CSF) examination revealed that cell count and protein values were increased. The patient also had an increased titer of anti-HTLV-1 antibodies in serum and CSF and was diagnosed with HTLV-1 associated myelopathy (HAM). She was treated with steroids, and her symptoms improved. Distinguishing HAM from ALS may be difficult because HAM may present with unilateral spastic paralysis and may be accompanied by fasciculation. Careful and accurate evaluation is necessitated to differentiate between these conditions for a conclusive diagnosis. (Received 1 March, 2021; Accepted 26 April, 2021; Published 1 September, 2021).

Self-remitting Elevation of Adenosine Deaminase Levels in the Cerebrospinal Fluid with Autoimmune Glial Fibrillary Acidic Protein Astrocytopathy: A Case Report and Review of the Literature.

A 29-year-old man presented with a high-grade fever, headache, and urinary retention, in addition to meningeal irritation and myoclonus in his upper extremities. A cerebrospinal fluid (CSF) examination showed pleocytosis and high adenosine deaminase (ADA) levels with no evidence of bacterial infection, including Mycobacterium tuberculosis. T2-weighted brain magnetic resonance imaging showed transient hyper-intensity lesions at the splenium of the corpus callosum (SCC), bilateral putamen, and pons during the course of the disease. The CSF was positive for anti-glial fibrillary acidic protein (GFAP) antibodies. He was diagnosed with autoimmune GFAP astrocytopathy. The present case shows that the combination of an elevated ADA level in the CSF and reversible T2-weighted hyper-intensity on the SCC supports the diagnosis of autoimmune GFAP encephalopathy.

Albumin-bilirubin score for predicting neuropsychiatric symptoms in patients receiving ifosfamide-based chemotherapy.

WHAT IS KNOWN AND OBJECTIVE: Ifosfamide, an alkylating agent, is widely used in the treatment of malignant diseases. However, these treatments are often limited due to the incidence of neuropsychiatric symptoms such as delirium, seizures, hallucinations and agitation. In this study, we examined risk factors for neuropsychiatric symptoms in patients receiving ifosfamide-based chemotherapy. METHODS: The study cases were patients with cancer receiving ifosfamide-based chemotherapy between April 2007 and March 2018. Risk analysis for ifosfamide-related neuropsychiatric symptoms was determined by time-dependent Cox proportional hazard regression analysis. RESULTS AND DISCUSSION: Of 183 eligible patients, 32 patients (17.5%) experienced ifosfamide-related neuropsychiatric symptoms. Time-dependent Cox proportional hazard model showed that the albumin-bilirubin (ALBI) score was significantly correlated with the incidence of ifosfamide-related neuropsychiatric symptoms (hazard ratio [HR] =1.45, 95% confidence interval [CI] = 1.05-2.01, p = 0.025). Additionally, there were correlations between the predicted risk of neuropsychiatric symptoms and ifosfamide-dose per cycle (HR =0.51, 95% CI = 0.27-0.94, p = 0.030) and creatinine clearance (Ccr) (HR = 0.53, 95% CI = 0.28-1.00, p = 0.050). In contrast, neither serum albumin nor total bilirubin was a significant risk factor for neuropsychiatric symptoms. WHAT IS NEW AND CONCLUSION: These findings indicate that ALBI score may be a useful biomarker for predicting neuropsychiatric symptoms in patients receiving ifosfamide-based chemotherapy.

Clinicopathological findings of a mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes/Leigh syndrome overlap patient with a novel m.3482A>G mutation in MT-ND1.

We report clinicopathological findings of a patient with mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes/Leigh syndrome (MELAS/LS) associated with a novel m.3482A>G mutation in MT-ND1. A 41-year-old woman had experienced multiple stroke-like episodes since age 16. She developed akinetic mutism two months before admission to our hospital. Neurological examination revealed akinetic mutism, bilateral deafness, and muscular atrophy. Cerebrospinal fluid tests revealed elevated pyruvate and lactate levels. Fluid-attenuated inversion recovery images on magnetic resonance imaging showed hyperintense areas in the right frontal and both sides of temporal and occipital lobes, both sides of the striatum, and the midbrain. Muscle biopsy revealed strongly succinate dehydrogenase-reactive blood vessels. L-arginine therapy improved her consciousness and prevented further stroke-like episodes. However, she died from aspiration pneumonia. Postmortem autopsy revealed scattered infarct-like lesions with cavitation in the cerebral cortex and necrotic lesions in the striatum and midbrain. The patient was pathologically confirmed as having MELAS/LS based on two characteristic clinicopathological findings: presenting MELAS/LS overlap phenotype and effectiveness of L-arginine treatment.

Clinical evaluation of childhood cerebral adrenoleukodystrophy with balint's symptoms.

BACKGROUND: Childhood cerebral adrenoleukodystrophy (CCALD) is the most common phenotype of adrenoleukodystrophy (ALD) and is characterized by the progression of intellectual, psychic, visual, and gait disturbances. Progression of this intractable disease can only be prevented by hematopoietic stem cell transplantation during the early stages of the disease. The aim of this study was to clinically evaluate children with CCALD who have visual symptoms to enable early diagnosis. METHODS: We enrolled 41 Japanese children with CCALD who had visual symptoms. We retrospectively analyzed age of onset, past medical history, initial symptoms, visual symptoms and findings on brain magnetic resonance imaging. RESULTS: The median age of disease onset was 7 years (range 5-10 years). The most common visual symptom was strabismus (n = 22). There was only one patient with the triad of symptoms of Balint's syndrome. Seventeen patients had incomplete Balint's syndrome and showed one or two of the triad of symptoms. Almost all patients with complete or incomplete Balint's syndrome showed bilateral parieto-occipital white matter lesions. CONCLUSIONS: CCALD could develop into Balint's syndrome, especially the incomplete form. Therefore, CCALD should be considered when boys show new symptoms, including lack of eye contact or bumping into objects.