Evaluation of the applicability of weak shoulder and arm sparing signs in amyotrophic lateral sclerosis by multiple neurologists and neurology residents: A single-center study.

INTRODUCTION/AIMS: Amyotrophic lateral sclerosis (ALS) exhibits selective muscle weakness. The weak shoulder and arm sparing signs, assessed by a single experienced neurologist, have been reported to be superior to previous signs in sensitivity and specificity. However, it is unknown whether the same results are observed when assessed by multiple neurologists. METHODS: Subjects were retrospectively identified from our department's inpatient database from 2014 to 2023. Medical Research Council (MRC) scores of the deltoid (Del), biceps brachii (BB), triceps brachii (TB), and first dorsal interosseous (FDI) muscles were evaluated. The weak shoulder sign was defined as positive when Del was weaker than BB and TB. The arm sparing sign was defined as positive when both Del and FDI were weaker than BB and TB. Sensitivity was analyzed in all ALS patients and in subgroups based on the region of symptom onset, presence or absence of upper motor neuron (UMN) signs, and the Japanese ALS Severity Classification. RESULTS: Seventy-one patients with ALS were identified. Eight neurologists and three neurology residents evaluated each patient's MRC scores. The weak shoulder and arm sparing signs were observed in 72% and 48% of patients, respectively, with no significant difference in sensitivity across patient subgroups. DISCUSSION: The weak shoulder and arm sparing signs showed high and moderate sensitivity, respectively, consistent with a previous report, even when evaluated by multiple examiners. This expands the clinical utility and increases the reliability of these signs, potentially contributing to accurate ALS diagnosis when combined with other clinical features and objective assessments.

High frequency of HTRA1 AND ABCC6 mutations in Japanese patients with adult-onset cerebral small vessel disease.

BACKGROUND: This study aimed to clarify the frequency and clinical features of monogenic cerebral small vessel disease (mgCSVD) among patients with adult-onset severe CSVD in Japan. METHODS: This study included patients with adult-onset severe CSVD with an age of onset ≤55 years (group 1) or >55 years and with a positive family history (group 2). After conducting conventional genetic tests for NOTCH3 and HTRA1, whole-exome sequencing was performed on undiagnosed patients. Patients were divided into two groups according to the results of the genetic tests: monogenic and undetermined. The clinical and imaging features were compared between the two groups. RESULTS: Group 1 and group 2 included 75 and 31 patients, respectively. In total, 30 patients had NOTCH3 mutations, 11 patients had HTRA1 mutations, 6 patients had ABCC6 mutations, 1 patient had a TREX1 mutation, 1 patient had a COL4A1 mutation and 1 patient had a COL4A2 mutation. The total frequency of mutations in NOTCH3, HTRA1 and ABCC6 was 94.0% in patients with mgCSVD. In group 1, the frequency of a family history of first relatives, hypertension and multiple lacunar infarctions (LIs) differed significantly between the two groups (monogenic vs undetermined; family history of first relatives, 61.0% vs 25.0%, p=0.0015; hypertension, 34.1% vs 63.9%, p=0.0092; multiple LIs, 87.8% vs 63.9%, p=0.0134). CONCLUSIONS: More than 90% of mgCSVDs were diagnosed by screening for NOTCH3, HTRA1 and ABCC6. The target sequences for these three genes may efficiently diagnose mgCSVD in Japanese patients.

Mimic of transient ischemic attack by anemia-induced asterixis: A novel differential diagnosis of stroke with critical pitfalls.

As most cases of asterixis with metabolic causes are asymptomatic, they have not been considered in the differential diagnosis of stroke. However, an asterixis occasionally resembles a transient ischemic attack (TIA). On the other hand, reports have indicated that anemia is an independent risk factor for brain ischemia. Therefore, both asterixis and anemia are important considerations for stroke diagnosis. A 79-year-old man with frequent leg palsy was initially diagnosed with recurrent TIA at the anterior cerebral artery (ACA) with a tiny callosal infarction and aspirin was prescribed immediately. However, subsequent careful physical examination revealed asterixis at both the wrist and knee joints. Laboratory testing and colonoscopy revealed severe anemia secondary to colon cancer. Blood transfusion immediately improved the asterixis and gait, thus confirming that anemia contributed to the patient's symptoms. This novel etiology of asterixis may be accompanied by misleading anemia-induced brain ischemic lesions detectable on magnetic resonance imaging (MRI). Anemia-induced asterixis should be considered as a novel differential diagnosis of a stroke to avoid pitfalls leading to unnecessary stroke treatment for patients with anemia.

Tic Movement of Thyroid Cartilage as a Cause for Localized Cerebral Embolism: Mimics of Embolic Stroke of Undetermined Source with Non-Stenotic Carotid Plaque.

Several studies have suggested that non-stenotic carotid plaque was a risk factor for embolic stroke of undetermined source in some patients. However, individual backgrounds of these patients is unclear. We encountered a 64-years-old female with cerebral emboli, from an apparently stable non-stenotic carotid plaque (only 1.42mm thick) at the distal left common carotid artery, caused by violent tic movement of thyroid cartilage under well controlled dyslipidemia. Even though the plaque appeared thin and stable, mechanical stimulation could cause multiple, unnaturally localized emboli by stimulation-induced atherogenesis and plaque rupture, resulting in a misdiagnose of embolic stroke of undetermined source with non-stenotic carotid plaque.

Inflammatory myopathy associated with PD-1 inhibitors.

OBJECTIVE: To characterize the inflammatory myopathy associated with programmed cell death 1 inhibitors (PD-1 myopathy). METHODS: We studied 19 Japanese patients with PD-1 myopathy (13 men and 6 women, mean age 70 years), who were referred to Keio University. As control groups, we used 68 patients with anti-signal recognition particle antibodies, 51 patients with anti-aminoacyl transfer RNA synthetase antibodies and 460 healthy subjects. RESULTS: In regard to muscle-disease severity, 10 patients showed a mild form of disease and 9 patients showed a severe form. Non-small cell lung cancer was the most common underlying cancer. PD-1 inhibitor consisted of 11 nivolumab and 8 pembrolizumab. PD-1 myopathy occurred 29 days on average after the first administration of PD-1 inhibitor. The initial manifestation of muscle weakness was ptosis in 10 patients, 15 patients had ptosis, 13 diplopia, 8 facial muscle weakness, 10 bulbar symptoms, 13 limb weakness, 14 neck weakness, 4 cardiac involvement, 6 respiratory involvement and 16 myalgia. Ocular, facial, cardiac and respiratory involvement and myalgia were more frequently observed than controls. Serum creatine kinase was increased to 5247 IU/L on average. Autoantibodies related to inflammatory myopathy were negative, while anti-striational antibodies were found in 13 (68%) patients. HLA-C*12:02 alleles were more frequently detected than healthy controls. Muscle pathology was characterized by multifocal necrotic myofibers with endomysial inflammation and expression of MHC class I. Immunosuppressive therapy with corticosteroids was generally effective for muscle weakness. CONCLUSIONS: Based on our clinical, histological and immunological findings, PD-1 myopathy is a discrete subset of inflammatory myopathy.

Diagnostic uncertainty of steroid-modified Marburg's variant of multiple sclerosis even at autopsy: A case suggesting lymphoma and related myelin loss.

MS (multiple sclerosis) has specific criteria to avoid misdiagnosis. However, the Marburg variant of MS is so fulminant that initial axonal damage and other atypical observations have been allowed in past reports. We present a 74-year-old autopsy case with a vanishing tumor after steroids and radiation therapy, which was pathologically diagnosed as a Marburg variant with initial axonal loss. The case displayed radiological lymphoma-like observations: mass effects protruding to the lateral ventricle, fused extension from the choroid plexus to white matter with C opening sign, a growing lesion from the skull dura mater, high in diffusion-weighted imaging and low in apparent diffusion coefficient on magnetic resonance imaging (MRI) suggesting high cell density lymphoma. In addition, clinical manifestations were atypical for MS: upper limb monoplegia without ipsilateral lower limb involvement, pleocytosis over 50 cells/µL, and class 3 cytological abnormality in cerebrospinal fluid. However, at autopsy following steroids and radiation therapy, there were no lymphoma-like lesions, such as mass effects, fused extensive lesions, masses on the skull dura mater, or high cell density lesions. Instead, there were only myelin losses corresponding to the MRI lesions, highlighting the potential for contamination by other diseases in steroid-modified Marburg's variant of multiple sclerosis, possibly due to lymphoma, even at autopsy.

Case Report: Anti-mGluR5 antibody-negative Ophelia syndrome with failed lymph node biopsy due to steroid therapy.

Ophelia syndrome is paraneoplastic limbic encephalitis (PLE) with Hodgkin lymphoma. Some Ophelia syndrome patients have been reported as testing positive for anti-metabotropic glutamate receptor 5 (mGluR5) antibodies. However, we experienced a case of anti-mGluR5 antibody-negative Ophelia syndrome. The type of onset, neurological symptoms, and imaging as well as electroencephalographic findings were like previous reports except for a normal cell count in cerebrospinal fluid (CSF). Unfortunately, a lymph node biopsy failed and could not diagnose the patient before death because steroid treatment for limbic encephalitis had shrunk lymph nodes. We believe it is essential to accumulate cases of this syndrome and clarify the association between PLE and Hodgkin lymphoma so chemotherapy can be initiated even if malignant lymphoma cannot be pathologically proven or when antibodies cannot be measured or are negative.

Distressing Belching with Chorea Induced by Caudate Infarction.

Although belching is mostly associated with gastrointestinal disorders, it occasionally accompanies movement disorders such as Parkinsonism or dystonia. A woman in her 80s presented distressing belching and chorea of the right arm and leg from 3 years earlier. A brain MRI showed a left caudate infarction and atrophic change. Haloperidol significantly improved belching and chorea. Caudate infarction can cause distressing belching with chorea. It might be important to select the appropriate drug by referring to the accompanying involuntary movement to treat belching with movement disorders.

Focal brain lactate accumulation in metformin-induced encephalopathy without systemic lactic acidosis: A case report suggesting mitochondrial vulnerability in lentiform fork sign.

Metformin causes metabolic encephalopathy in some patients with end-stage chronic kidney disease, resulting in impaired consciousness and parkinsonism. This encephalopathy has a very characteristic magnetic resonance imaging feature in lentiform nuclei known as the "lentiform fork sign". However, the mechanism is unknown. Here, we report a case of metformin-induced encephalopathy with a novel observation of lactate accumulation in the lentiform nuclei on magnetic resonance spectroscopy without systemic lactic acidosis. Since metformin is an inhibitor of mitochondrial complex-I, this focal brain lactate accumulation implies that a part of the pathogenesis of metformin-induced encephalopathy is the focal vulnerability of mitochondria to metformin in the lentiform nuclei. When metformin causes encephalopathy, not only testing for serum lactic acidosis and performing routine magnetic resonance imaging but also evaluation of brain lactate accumulation by magnetic resonance spectroscopy should be required to elucidate the etiology.

Hidden relationship between fingolimod and bleeding: Possible novel management of fingolimod-associated lymphopenia.

Fingolimod, a functional antagonist of sphingosine-1 phosphate receptor, is a disease modifying drug of multiple sclerosis and its remarkable adverse effect is peripheral lymphopenia because the drug retains lymphocyte in the secondary lymphoid tissues. Therefore, in theory, when severe bleedings occurred, the fingolimod-treated patients could not compensate for the loss of lymphocytes induced by bleedings because of the retention in the secondary lymphoid tissues. In addition, because most of the fingolimod is reported to be distributed in the erythrocytes, and the erythrocytes are the main regulator of serum sphingosine-1 phosphate concentration, bleeding may also affect metabolism of fingolimod and prognosis of multiple sclerosis. However, no study had focused the relationship between fingolimod and bleedings in multiple sclerosis. We encountered the first case in which fingolimod-associated lymphopenia worsened synchronously with gynecological bleeding, and was improved by the bleeding prophylaxis, uterine myomectomy. This case had statistically significant positive correlation between the serum hemoglobin level and peripheral lymphocyte count (P = 0.0000000507). We then had three similar cases. In these 4 correlative patients out of the 14 fingolimod-treated patients in our institution, the importance of the bleeding in fingolimod-treated patients was indicated by line graphs, point diagrams, and statistically significant correlation coefficients. Bleeding should be focused on by all of physicians treating multiple sclerosis with fingolimod.

HTRA1-Related Cerebral Small Vessel Disease: A Review of the Literature.

Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL) is clinically characterized by early-onset dementia, stroke, spondylosis deformans, and alopecia. In CARASIL cases, brain magnetic resonance imaging reveals severe white matter hyperintensities (WMHs), lacunar infarctions, and microbleeds. CARASIL is caused by a homozygous mutation in high-temperature requirement A serine peptidase 1 (HTRA1). Recently, it was reported that several heterozygous mutations in HTRA1 also cause cerebral small vessel disease (CSVD). Although patients with heterozygous HTRA1-related CSVD (symptomatic carriers) are reported to have a milder form of CARASIL, little is known about the clinical and genetic differences between the two diseases. Given this gap in the literature, we collected clinical information on HTRA1-related CSVD from a review of the literature to help clarify the differences between symptomatic carriers and CARASIL and the features of both diseases. Forty-six symptomatic carriers and 28 patients with CARASIL were investigated. Twenty-eight mutations in symptomatic carriers and 22 mutations in CARASIL were identified. Missense mutations in symptomatic carriers are more frequently identified in the linker or loop 3 (L3)/loop D (LD) domains, which are critical sites in activating protease activity. The ages at onset of neurological symptoms/signs were significantly higher in symptomatic carriers than in CARASIL, and the frequency of characteristic extraneurological findings and confluent WMHs were significantly higher in CARASIL than in symptomatic carriers. As previously reported, heterozygous HTRA1-related CSVD has a milder clinical presentation of CARASIL. It seems that haploinsufficiency can cause CSVD among symptomatic carriers according to the several patients with heterozygous nonsense/frameshift mutations. However, the differing locations of mutations found in the two diseases indicate that distinct molecular mechanisms influence the development of CSVD in patients with HTRA1-related CSVD. These findings further support continued careful examination of the pathogenicity of mutations located outside the linker or LD/L3 domain in symptomatic carriers.

Guillain-Barré Syndrome and Posterior Reversible Encephalopathy Syndrome following Spinal Surgery.

Guillain-Barré syndrome (GBS) typically occurs after gastroenteritis and respiratory tract infection, but surgery has also been considered one of the triggers. Posterior reversible encephalopathy syndrome (PRES) is a rare complication of GBS. A normotensive female in her 70s presented ascending paralysis and frontal-parieto-occipital subcortical lesions with intermittent hypertension after spinal surgery. Nerve conduction studies revealed demyelinating polyneuropathy. The patient's brain lesions disappeared with amelioration of hypertension. She was diagnosed with the demyelinating form of GBS and PRES caused by intermittent hypertension. Intravenous immunoglobulin G (IVIG) improved her symptoms without exacerbation of the PRES. Surgery can be a trigger of GBS, and GBS can cause PRES by hypertension and present as central nervous lesions. It is important to treat hypertension before using IVIG when PRES is suspected as a complication of GBS, since the encephalopathy can be exacerbated by IVIG. There may be more undiagnosed cases of the coexistence of GBS and PRES after surgery because surgery itself can also cause PRES. Proper control of blood pressure and confirmation of negative central nervous lesions are required to treat GBS patients with IVIG safely.