TWNK Gene Associated Perrault Syndrome Patient with Neurological Features

Perrault syndrome 5 is a rare autosomal recessive disorder that is characterized by the association of sensorineural hearing loss and ovarian dysgenesis in females with diversity of neurologic deficits due to variants of twinkle mtDNA helicase (TWNK) gene. Since neurologic deficits develop gradually, patient is often misdiagnosed with other neurological disease during early age. Herein, we report a case of genetically diagnosed Perrault syndrome 5.

Association Between Suggestive Symptom of Restless Legs Syndrome and COVID-19 Vaccination: A Pilot Study

Objectives@#Various sensory symptoms have been recognized after COVID-19 vaccination. Here, we aimed to explore the association between the suggestive symptom of restless legs syndrome (RLSss) and COVID-19 vaccination using an online survey. @*Methods@#We prospectively studied participants who were working in our hospital after at least the first dose of the ChAdOx1 or BNT162b2 mRNA vaccine. The participants were invited via smartphone messages and voluntarily filled out an online questionnaire that included adverse events after vaccination. We considered the participants as having RLSss if they reported that they had three or more symptoms in the restless legs syndrome (RLS) diagnostic criteria. @*Results@#A total of 628 participants (506 female; mean age, 37.7±12.4 years) responded fully to our online survey. 588 participants (93.6%) received the first dose of the ChAdOx1 vaccine (BNT162b2 mRNA vaccine for 40 participants). A total of 44 out of the 628 participants (7.0%) reported that they had RLSss. Myalgia was more common in participants with RLSss than in those without RLSss (97.7% vs. 67.3%, p<0.001). Multivariate testing showed that age (odds ratio, 1.037 per 1 year increase; 95% CI, 1.004–1.071) and the presence of myalgia (odds ratio, 20.479; 95% CI, 4.266–368.206) were associated with the presence of RLSss. @*Conclusions@#This pilot study explored RLSss after COVID-19 vaccination and the results suggested that RLS might be one of the causes of adverse symptoms after COVID-19 vaccination. Further studies are required to confirm the relationship between RLS and COVID-19 vaccination.

Results of a Survey on Diagnostic Procedures and Treatment Choices for Neuromyelitis Optica Spectrum Disorder in Korea: Beyond the Context of Current Clinical Guidelines

Background@#and Purpose Neuromyelitis optica spectrum disorder (NMOSD) is a rare demyelinating disease of the central nervous system (CNS). We investigated the medical behaviors of experts in Korea when they are diagnosing and treating NMOSD. @*Methods@#An anonymous questionnaire on the diagnosis and treatment of NMOSD was distributed to experts in CNS demyelinating diseases. @*Results@#Most respondents used the 2015 diagnostic criteria for NMOSD and applied a cerebrospinal fluid examination, magnetic resonance imaging (MRI) of the brain and spine, and anti-aquaporin-4 antibody testing to all suspected cases of NMOSD. All respondents prescribed steroid pulse therapy as an first-line therapy in the acute phase of NMOSD, and 67% prescribed azathioprine for maintenance therapy in NMOSD. However, details regarding monitoring, the tapering period of oral steroids, second-line therapy use in refractory cases, management during pregnancy, and schedule of follow-up MRI differed according to the circumstances of individual patients. We analyzed the differences in response rates between two groups of respondents according to the annual number of NMOSD patients that they treated.The group that had been treating ≥10 NMOSD patients annually preferred rituximab more often as the second-line therapy (p=0.011) and had more experience with rituximab treatment (p=0.015) compared with the group that had been treating <10 NMOSD patients. @*Conclusions@#This study has revealed that NMOSD experts in Korea principally follow the available treatment guidelines. However, the differences in specific clinical practices applied to uncertain cases that have been revealed will need to be investigated further in order to formulate suitable recommendations.

Multicenter Targeted Population Screening of Late Onset Pompe Disease in Unspecified Myopathy Patients in Korea

Background@#Pompe disease is a rare autosomal recessive disorder caused by the deficiency of a lysosomal enzyme, acid alpha-glucosidase (GAA). Early diagnosis and initiation of treatment with enzyme replacement therapy have remarkable effects on the prognosis of Pompe disease. We performed the expanded screening for late onset Pompe disease (LOPD) at eight centers in Korea. @*Methods@#From September 1, 2015, GAA activity were measured from both dried blood spot (DBS) and mixed leukocyte for 188 available patients. For 12 patients with low GAA activity, we performed Sanger sequencing of GAA gene. @*Results@#Among 188 patients, 115 were males. The mean of age of symptom onset and diagnosis were 34.3 years and 41.6 years. Among 12 patients with decreased GAA activity, two patients were confirmed to have LOPD with genetic test (c.1316T>A [p.M439K] + c.2015G>A [p.R672Q], c.1857C>G [p.S619R] + c.546G>C [leaky splicing]). Other two patients had homozygous G576S and E689K mutation, known as pseudodeficiency allele. @*Conclusions@#This study is expanded study of LOPD screening for targeted Korean population. We found two patients with LOPD, and the detection rate of LOPD is 1.06%. With application of modified GAA cutoff value (0.4), which was previously reported, there were no false positive results of GAA activity test using DBS. Therefore, it could be an appropriate screening test for LOPD in especially East-Asian population, in which pseudodeficiency allele is frequent.

Multicenter Targeted Population Screening of Late Onset Pompe Disease in Unspecified Myopathy Patients in Korea

Background@#Pompe disease is a rare autosomal recessive disorder caused by the deficiency of a lysosomal enzyme, acid alpha-glucosidase (GAA). Early diagnosis and initiation of treatment with enzyme replacement therapy have remarkable effects on the prognosis of Pompe disease. We performed the expanded screening for late onset Pompe disease (LOPD) at eight centers in Korea. @*Methods@#From September 1, 2015, GAA activity were measured from both dried blood spot (DBS) and mixed leukocyte for 188 available patients. For 12 patients with low GAA activity, we performed Sanger sequencing of GAA gene. @*Results@#Among 188 patients, 115 were males. The mean of age of symptom onset and diagnosis were 34.3 years and 41.6 years. Among 12 patients with decreased GAA activity, two patients were confirmed to have LOPD with genetic test (c.1316T>A [p.M439K] + c.2015G>A [p.R672Q], c.1857C>G [p.S619R] + c.546G>C [leaky splicing]). Other two patients had homozygous G576S and E689K mutation, known as pseudodeficiency allele. @*Conclusions@#This study is expanded study of LOPD screening for targeted Korean population. We found two patients with LOPD, and the detection rate of LOPD is 1.06%. With application of modified GAA cutoff value (0.4), which was previously reported, there were no false positive results of GAA activity test using DBS. Therefore, it could be an appropriate screening test for LOPD in especially East-Asian population, in which pseudodeficiency allele is frequent.

Prevalence and Incidence of Neuromyelitis Optica Spectrum Disorderin Korea: Population Based Study

Background@#Although neuromyelitis optica spectrum disorder (NMOSD) is known to be a rare disease, its prevalence and incidence have not yet been studied in Korea. We performed a population-based study to examine the prevalence and incidence of NMOSD in Korea using data from the Korean National Health Insurance (NHI) claims database. @*Methods@#Data from 2013 to 2017 were obtained, with a washout period set as 2013 and 2014. The prevalence and incidence of NMOSD in 2016 and 2017 were calculated using population census data. Subjects were divided into 5 groups at 15-year intervals, depending on the age at which the diagnostic code was entered. The relative risk (RR) for each age group was compared with the oldest (≥ 60 years) age group. @*Results@#The overall prevalence was estimated to be 3.36 and 3.56 per 100,000 individuals, with an incidence of 0.41 and 0.65 per 100,000 individuals-year in 2016 and 2017, respectively. The mean age was 43.08 (standard deviation, 14.56) years, and the ratio of male to females was 1:4.7. The incidence was higher in female individuals aged between 30 and 59 years (RR, 2.8–3.05; P < 0.05). @*Conclusion@#Nationwide prevalence of NMOSD in Korea was 3.36 and 3.56/100,000 and its incidence was 0.41 and 0.65/100,000-year in 2016 and 2017 respectively.

Central Sleep Apnea without Cheyne-Stokes Breathing Following an Acute Cerebral Infarction

Central sleep apnea (CSA) is attributed to medical or neurological conditions including stroke. The association of lesion location and CSA in patients with ischemic stroke has not been well elucidated. A 69-year-old man with a history of hypertension and diabetes mellitus was admitted due to stroke. The brain magnetic resonance imaging showed an acute ischemic stroke in the right ventral thalamus and adjacent hypothalamus. During hospitalization, polysomnography (PSG) was performed because repetitive cessation of respiration during sleep was observed by chance. PSG showed severe CSA; the apnea-hypopnea index (AHI) was 73.5 with a minimum oxygen saturation of 89% and central apnea index (CAI) was 63.0. Two years later, follow-up PSG showed that AHI was 7.2 with a minimum oxygen saturation of 91% and CAI was 1.0. We report the patient with CSA after ischemic stroke with right thalamus and adjacent hypothalamus, which resolved spontaneously with time.

‘Sirim’ (Cold) Pain as a Common Symptom in Korean Patients with Clinically Suspected Small-Fiber Neuropathy

BACKGROUND AND PURPOSE: Diagnosing small-fiber neuropathy (SFN) is challenging because there is no gold-standard test and few diagnostic tests. This study investigated the clinical symptom profile and its associations with the results of quantitative sensory testing (QST) and the quantitative sudomotor axon reflex test (QSART) as well as the quality of life (QOL) in patients with clinically suspected SFN. METHODS: This study involved 63 patients with clinically suspected length-dependent SFN. Assessments were performed using QST, QSART, SFN Symptoms Inventory Questionnaire, Neuropathic Pain Symptom Inventory, ‘Sirim’ frequency and ‘Sirim’ (cold) pain severity, and 36-item Short-Form Health Survey. Multiple logistic and linear regression analyses were performed to predict risk factors for QST or QSART abnormalities and QOL, respectively. RESULTS: ‘Sirim’ and ‘Sirim’ pain was the most-common (84%) and the most-severe complaint (mean score of 6.3 on a numerical rating scale ranging from 0 to 10) in patients with clinically suspected SFN. The findings of QST [cold detection threshold (CDT)] and QSART were abnormal in 71% (n=45/57) and 62% (n=39/56) of the patients, respectively. An abnormal CDT was correlated with more-severe stabbing pain (odds ratio=2.23, 95% CI=1.02–4.87, p=0.045). Restless-leg symptoms (β=−7.077) and pressure-evoked pain (β=−5.034) were independent predictors of the physical aspects of QOL. CONCLUSIONS: ‘Sirim’ pain, similar to cold pain, should be considered a major neuropathic pain in SFN. Among pain characteristics, stabbing pain of a spontaneous paroxysmal nature may be more pronounced in the setting of dysfunctional Aδ fibers with functional autonomic C fibers.

Characteristics of South Korean Patients with Hereditary Transthyretin Amyloidosis

BACKGROUND AND PURPOSE: This retrospective cross-sectional study included 18 patients from unrelated families harboring mutations of the transthyretin gene (TTR), and analyzed their characteristics and geographical distribution in South Korea. METHODS: The included patients had a diagnosis of systemic amyloidosis, clinical symptoms, such as amyloid neuropathy or cardiomyopathy, and confirmation of a TTR gene mutation using genetic analysis recorded between April 1995 and November 2014. RESULTS: The mean age at disease onset was 49.6 years, and the mean disease duration from symptom onset to diagnosis was 3.67 years. Fifteen of the 18 patients were classified as mixed phenotype, 2 as the neurological phenotype, and only 1 patient as the cardiac phenotype. The most-common mutation pattern in South Korea was Asp38Ala, which was detected in eight patients. Thirteen patients reported their family hometowns, and five of the eight harboring the Asp38Ala mutation were from the Gyeongsang province in southeast Korea. The other eight patients exhibited a widespread geographical distribution. A particularly noteworthy finding was that the valine at position 30 (Val30Met) mutation, which was previously reported as the most-common TTR mutation worldwide and also the most common in the Japanese population, was not detected in the present South Korean patients. CONCLUSIONS: South Korean patients with hereditary TTR amyloidosis exhibited heterogeneous TTR genotypes and clinical phenotypes. The findings of this study suggest that the distribution of TTR amyloidosis in South Korea is due to de novo mutations and/or related to the other countries in East Asia.

Hypercoagulability and Mortality of Patients with Stroke and Active Cancer: The OASIS-CANCER Study / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: Patients with active cancer are at an increased risk for stroke. Hypercoagulability plays an important role in cancer-related stroke. We aimed to test whether 1) hypercoagulability is a predictor of survival, and 2) correction of the hypercoagulable state leads to better survival in patients with stroke and active cancer. METHODS: We recruited consecutive patients with acute ischemic stroke and active systemic cancer between January 2006 and July 2015. Hypercoagulability was assessed using plasma D-dimer levels before and after 7 days of anticoagulation treatment. The study outcomes included overall and 1-year survival. Plasma D-dimer levels before and after treatment were tested in univariate and multivariate Cox regression models. We controlled for systemic metastasis, stroke mechanism, age, stroke severity, primary cancer type, histology, and atrial fibrillation using the forward stepwise method. RESULTS: A total of 268 patients were included in the analysis. Patients with high (3rd–4th quartiles) pre-treatment plasma D-dimer levels showed decreased overall and 1-year survival (adjusted HR, 2.19 [95% CI, 1.46–3.31] and 2.70 [1.68–4.35], respectively). After anticoagulation treatment, post-treatment D-dimer level was significantly reduced and independently associated with poor 1-year survival (adjusted HR, 1.03 [95% CI, 1.01–1.05] per 1 μg/mL increase, P=0.015). The successful correction of hypercoagulability was a protective factor for 1-year survival (adjusted HR 0.26 [CI 0.10–0.68], P=0.006). CONCLUSIONS: Hypercoagulability is associated with poor survival after stroke in patients with active cancer. Effective correction of hypercoagulability may play a protective role for survival in these patients.

Clinical Characteristics and Treatment Response of Peripheral Neuropathy in the Presence of Eosinophilic Granulomatosis with Polyangiitis (Churg-Strauss Syndrome): Experience at a Single Tertiary Center

BACKGROUND AND PURPOSE: Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare systemic small-vessel vasculitis accompanied by asthma, eosinophilia, and eosinophilic inflammation of various tissues including the peripheral nerves. This study investigated the clinical course and long-term outcomes of peripheral neuropathy in patients with EGPA. METHODS: Seventy-one patients with physician-diagnosed EGPA were identified at Samsung Medical Center between January 1995 and April 2014. Sixty-one of these patients were followed-up for more than 1 year and received corticosteroid therapy with or without intravenous cyclophosphamide pulse therapy for 6 to 18 months. Medical records of the 61 patients including demographic data, clinical features, laboratory and pathological findings, treatments, and outcomes were reviewed. RESULTS: Peripheral neuropathy as a manifestation of EGPA was present in 46 (75%) of the 61 patients. The mean follow-up duration of the patients with neuropathy was 6.4 years (range 1.2–18.8 years). The scores on the neurological functional disability scale before and after the combination treatment with corticosteroid and cyclophosphamide were 2.43±0.86 and 0.54±0.95 (mean±SD; p<0.001), respectively. The peripheral neuropathy relapsed in one patient. CONCLUSIONS: The long-term clinical outcome of peripheral neuropathy in patients with EGPA receiving initial corticosteroid and cyclophosphamide combination therapy was favorable with a very low relapse rate.

Late-onset non-thymomatous myasthenia gravis: Comparison with early-onset and very late-onset myasthenia gravis

Objective: To identify the clinical characteristics of patients with myasthenia gravis (MG) according to age at onset. Methods: We retrospectively recruited 227 non-thymomatous MG patients with adult onset who had been followed up for more than one year. The patients were classified based on the age of symptom onset as “early-onset MG” (EOMG,18–50 years; N=135), “late-onset MG” (LOMG, 50–64 years; N=53), and “very late-onset MG” (VLOMG, 65 years; N=39). Clinical features and serological findings were compared between these groups. Results: LOMG patients showed more frequent ocular MG (55%) and less frequent thymic hyperplasia (9%) compared to EOMG patients (31% and 38%; p=0.006 and p<0.001, respectively), and no female preponderance compared to VLOMG patients (female, 49% vs.77%; p=0.014). However, there were no significant differences between VLOMG and EOMG patients, except for more frequent thymic hyperplasia (p<0.001) in EOMG patients. When analyzing female patients only, less frequent secondary generalization (10%) were additionally found in LOMG patients, compared to EOMG (47%, p= 0.008) and VLOMG (59%, p=0.004) patients. Anti-acetylcholine receptor antibody (HR, 5.48; 95% CI, 1.73–17.37; p=0.004) was independently associated with secondary generalization in female EOMG patients. Conclusion: Our study suggests that LOMG patients, especially female, were characterized by frequent ocular MG and less frequent secondary generalization, distinguished from EOMG and VLOMG patients. Further large epidemiologic studies in Korea are needed to determine the characteristics of MG patients according to the age at onset and gender.

Ischemic Stroke and Cancer: Stroke Severely Impacts Cancer Patients, While Cancer Increases the Number of Strokes

BACKGROUND: Cancer and ischemic stroke are two of the most common causes of death among the elderly, and associations between them have been reported. However, the main pathomechanisms of stroke in cancer patients are not well known, and can only be established based on accurate knowledge of the characteristics of cancer-related strokes. We review herein recent studies concerning the clinical, laboratory, and radiological features of patients with cancer-related stroke. MAIN CONTENTS: This review covers the epidemiology, underlying mechanisms, and acute and preventive treatments for cancer-related stroke. First, the characteristics of stroke (clinical and radiological features) and systemic cancer (type and extent) in patients with cancer-specific stroke are discussed. Second, the role of laboratory tests in the early identification of patients with cancer-specific stroke is discussed. Specifically, serum D-dimer levels (as a marker of a hypercoagulable state) and embolic signals on transcranial Doppler (suggestive of embolic origin) may provide clues regarding changes in the levels of coagulopathy related to cancer and anticoagulation. Finally, strategies for stroke treatment in cancer patients are discussed, emphasizing the importance of preventive strategies (i.e., the use of anticoagulants) over acute revascularization therapy in cancer-related stroke. CONCLUSION: Recent studies have revealed that the characteristics of cancer-related stroke are distinct from those of conventional stroke. Our understanding of the characteristics of cancer-related stroke is essential to the correct management of these patients. The studies presented in this review highlight the importance of a personalized approach in treating stroke patients with cancer.

Paroxysmal Horizontal Diplopia Related to Brainstem Lesion

Paroxysmal diplopia and dysarthria-ataxia have been reported in multiple sclerosis, stroke and Behcet's disease. We present a case of 25-year-old man with multiple brain lesions, who developed paroxysmal horizontal dysconjugate eyeball deviation, dysarthria and ataxia. Subtraction ictal SPECT co-registered to MR images demonstrated hyperperfusion in the brainstem and cerebellum during the paroxysms.