Repeat conformation heterogeneity in cerebellar ataxia, neuropathy, vestibular areflexia syndrome.

Cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) is a late-onset, slow-progressing multisystem neurodegenerative disorder. Biallelic AAGGG repeat expansion in RFC1 has been identified as causative of this disease, and repeat conformation heterogeneity (ACAGG repeat) was also recently implied. To molecularly characterize this disease in Japanese patients with adult-onset ataxia, we accumulated and screened 212 candidate families by an integrated approach consisting of flanking PCR, repeat-primed PCR, Southern blotting and long-read sequencing using Sequel II, GridION or PromethION. We identified 16 patients from 11 families, of whom seven had ACAGG expansions [(ACAGG)exp/(ACAGG)exp] (ACAGG homozygotes), two had ACAGG and AAGGG expansions [(ACAGG)exp/(AAGGG)exp] (ACAGG/AAGGG compound heterozygotes) and seven had AAGGG expansions [(AAGGG)exp/(AAGGG)exp] (AAGGG homozygotes). The overall detection rate was 5.2% (11/212 families including one family having two expansion genotypes). Long-read sequencers revealed the entire sequence of both AAGGG and ACAGG repeat expansions at the nucleotide level of resolution. Clinical assessment and neuropathology results suggested that patients with ACAGG expansions have similar clinical features to previously reported patients with homozygous AAGGG expansions, although motor neuron involvement was more notable in patients with ACAGG expansions (even if one allele was involved). Furthermore, a later age of onset and slower clinical progression were implied in patients with ACAGG/AAGGG compound heterozygous expansions compared with either ACAGG or AAGGG homozygotes in our very limited cohort. Our study clearly shows the occurrence of repeat conformation heterogeneity, with possible different impacts on the affected nervous systems. The difference in disease onset and progression between compound heterozygotes and homozygotes might also be suspected but with very limited certainty due to the small sample number of cases in our study. Studies of additional patients are needed to confirm this.

Complete sequencing of expanded SAMD12 repeats by long-read sequencing and Cas9-mediated enrichment.

A pentanucleotide TTTCA repeat insertion into a polymorphic TTTTA repeat element in SAMD12 causes benign adult familial myoclonic epilepsy. Although the precise determination of the entire SAMD12 repeat sequence is important for molecular diagnosis and research, obtaining this sequence remains challenging when using conventional genomic/genetic methods, and even short-read and long-read next-generation sequencing technologies have been insufficient. Incomplete information regarding expanded repeat sequences may hamper our understanding of the pathogenic roles played by varying numbers of repeat units, genotype-phenotype correlations, and mutational mechanisms. Here, we report a new approach for the precise determination of the entire expanded repeat sequence and present a workflow designed to improve the diagnostic rates in various repeat expansion diseases. We examined 34 clinically diagnosed benign adult familial myoclonic epilepsy patients, from 29 families using repeat-primed PCR, Southern blot, and long-read sequencing with Cas9-mediated enrichment. Two cases with questionable results from repeat-primed PCR and/or Southern blot were confirmed as pathogenic using long-read sequencing with Cas9-mediated enrichment, resulting in the identification of pathogenic SAMD12 repeat expansions in 76% of examined families (22/29). Importantly, long-read sequencing with Cas9-mediated enrichment was able to provide detailed information regarding the sizes, configurations, and compositions of the expanded repeats. The inserted TTTCA repeat size and the proportion of TTTCA sequences among the overall repeat sequences were highly variable, and a novel repeat configuration was identified. A genotype-phenotype correlation study suggested that the insertion of even short (TTTCA)14 repeats contributed to the development of benign adult familial myoclonic epilepsy. However, the sizes of the overall TTTTA and TTTCA repeat units are also likely to be involved in the pathology of benign adult familial myoclonic epilepsy. Seven unsolved SAMD12-negative cases were investigated using whole-genome long-read sequencing, and infrequent, disease-associated, repeat expansions were identified in two cases. The strategic workflow resolved two questionable SAMD12-positive cases and two previously SAMD12-negative cases, increasing the diagnostic yield from 69% (20/29 families) to 83% (24/29 families). This study indicates the significant utility of long-read sequencing technologies to explore the pathogenic contributions made by various repeat units in complex repeat expansions and to improve the overall diagnostic rate.

GGC Repeat Expansion of NOTCH2NLC in Adult Patients with Leukoencephalopathy.

Leukoencephalopathies comprise a broad spectrum of disorders, but the genetic background of adult leukoencephalopathies has rarely been assessed. In this study, we analyzed 101 Japanese patients with genetically unresolved adult leukoencephalopathy using whole-exome sequencing and repeat-primed polymerase chain reaction for detecting GGC expansion in NOTCH2NLC. NOTCH2NLC was recently identified as the cause of neuronal intranuclear inclusion disease. We found 12 patients with GGC expansion in NOTCH2NLC as the most frequent cause of adult leukoencephalopathy followed by NOTCH3 variants in our cohort. Furthermore, we found 1 case with de novo GGC expansion, which might explain the underlying pathogenesis of sporadic cases. ANN NEUROL 2019;86:962-968.

Ataxic phenotype with altered CaV3.1 channel property in a mouse model for spinocerebellar ataxia 42.

Spinocerebellar ataxia 42 (SCA42) is a neurodegenerative disorder recently shown to be caused by c.5144G > A (p.Arg1715His) mutation in CACNA1G, which encodes the T-type voltage-gated calcium channel CaV3.1. Here, we describe a large Japanese family with SCA42. Postmortem pathological examination revealed severe cerebellar degeneration with prominent Purkinje cell loss without ubiquitin accumulation in an SCA42 patient. To determine whether this mutation causes ataxic symptoms and neurodegeneration, we generated knock-in mice harboring c.5168G > A (p.Arg1723His) mutation in Cacna1g, corresponding to the mutation identified in the SCA42 family. Both heterozygous and homozygous mutants developed an ataxic phenotype from the age of 11-20 weeks and showed Purkinje cell loss at 50 weeks old. Degenerative change of Purkinje cells and atrophic thinning of the molecular layer were conspicuous in homozygous knock-in mice. Electrophysiological analysis of Purkinje cells using acute cerebellar slices from young mice showed that the point mutation altered the voltage dependence of CaV3.1 channel activation and reduced the rebound action potentials after hyperpolarization, although it did not significantly affect the basic properties of synaptic transmission onto Purkinje cells. Finally, we revealed that the resonance of membrane potential of neurons in the inferior olivary nucleus was decreased in knock-in mice, which indicates that p.Arg1723His CaV3.1 mutation affects climbing fiber signaling to Purkinje cells. Altogether, our study shows not only that a point mutation in CACNA1G causes an ataxic phenotype and Purkinje cell degeneration in a mouse model, but also that the electrophysiological abnormalities at an early stage of SCA42 precede Purkinje cell loss.

[Analysis of Device-Related Infection after Deep Brain Stimulation Surgery].

BACKGROUND: Device-related infection frequently becomes a serious problem after deep brain stimulation(DBS)surgery and DBS device removal is usually the only effective treatment option. In this study, we examined risk factors for infection related to DBS devices at our institution. METHODS: We retrospectively investigated 80 DBS surgeries performed between March 2009 and September 2017 at our institution. We examined the relationship between DBS device-related infection and the following items:duration of electrode placement surgery, total number of tracks of microelectrode recordings(MER), period between surgeries, highest body temperature until implantable pulse generator(IPG)implantation, and patient background characteristics. RESULTS: Four(5.0%)patients developed device-related infection after DBS surgery. Three of them required device removal, whereas one improved following antibiotic treatment alone. We did not identify any specific trend or risk factor for infection. DISCUSSION: We perform DBS surgery in two stages. Patients were implanted with an IPG 2-3 days after electrode placement until August 2016, and at 6-8 days starting in September 2016. All cases of infection developed before September 2016, and no cases of infection have occurred since September 2016. We believe that lengthy surgical electrode placement affects the general status of patients and performing surgery before stabilization might confer a risk of infection. CONCLUSION: Device-related infection after DBS surgery does not seem to be associated with any risk factors. However, a shorter period between two-staged surgeries might affect infection rates.

CCR2(+)CCR5(+) T cells produce matrix metalloproteinase-9 and osteopontin in the pathogenesis of multiple sclerosis.

Multiple sclerosis (MS) is a demyelinating disease of the CNS that is presumably mediated by CD4(+) autoimmune T cells. Although both Th1 and Th17 cells have the potential to cause inflammatory CNS pathology in rodents, the identity of pathogenic T cells remains unclear in human MS. Given that each Th cell subset preferentially expresses specific chemokine receptors, we were interested to know whether T cells defined by a particular chemokine receptor profile play an active role in the pathogenesis of MS. In this article, we report that CCR2(+)CCR5(+) T cells constitute a unique population selectively enriched in the cerebrospinal fluid of MS patients during relapse but not in patients with other neurologic diseases. After polyclonal stimulation, the CCR2(+)CCR5(+) T cells exhibited a distinct ability to produce matrix metalloproteinase-9 and osteopontin, which are involved in the CNS pathology of MS. Furthermore, after TCR stimulation, the CCR2(+)CCR5(+) T cells showed a higher invasive potential across an in vitro blood-brain barrier model compared with other T cells. Of note, the CCR2(+)CCR5(+) T cells from MS patients in relapse are reactive to myelin basic protein, as assessed by production of IFN-γ. We also demonstrated that the CCR6(-), but not the CCR6(+), population within CCR2(+)CCR5(+) T cells was highly enriched in the cerebrospinal fluid during MS relapse (p < 0.0005) and expressed higher levels of IFN-γ and matrix metalloproteinase-9. Taken together, we propose that autoimmune CCR2(+)CCR5(+)CCR6(-) Th1 cells play a crucial role in the pathogenesis of MS.

The advances in the early and accurate diagnosis of Creutzfeldt-Jakob disease and other prion diseases: where are we today?

INTRODUCTION: Before the introduction of MRI diffusion-weighted images (DWI), the diagnosis of Creutzfeldt-Jakob disease (CJD) relied upon nonspecific findings including clinical symptoms, EEG abnormalities, and elevated levels of cerebrospinal fluid 14-3-3 protein. Subsequently, the use of DWI has improved diagnostic accuracy, but it sometimes remains difficult to differentiate CJD from encephalitis, epilepsy, and other dementing disorders. The revised diagnostic criteria include real-time quaking-induced conversion (RT-QuIC), detecting small amounts of CJD-specific prion protein, and clinically sensitive DWI. Combining these techniques has further improved diagnostic accuracy, enabling earlier diagnosis. AREAS COVERED: Herein, the authors review the recent advances in diagnostic methods and revised diagnostic criteria for sporadic CJD. They also discuss other prion diseases, such as variant CJD and chronic wasting disease, where the emergence of new types is a concern. EXPERT OPINION: Despite improvements in diagnostic methods and criteria, some subtypes of prion disease are still difficult to diagnose, and even the diagnosis using the most innovative RT-QuIC test remains a challenge in terms of accuracy and standardization. However, these revised criteria can be adapted to the emergence of new types of prion diseases. It is essential to continue careful surveillance and update information on the latest prion disease phenotypes.

Reduced likelihood of the Poggendorff illusion in cerebellar strokes: a clinical and neuroimaging study.

This study aimed to test our hypothesis that the cerebellum plays an important role in the generation of the optical-geometric illusion known as the Poggendorff illusion, the mechanism of which has been explained by accumulated experience with natural scene geometry. A total of 79 participants, comprising 28 patients with isolated cerebellar stroke, 27 patients with isolated cerebral stroke and 24 healthy controls, performed Poggendorff illusion tasks and 2 different control tasks. We also investigated core brain regions underpinning changes in the experience of the illusion effect using multivariate lesion-symptom mapping. Our results indicate that patients with isolated cerebellar stroke were significantly less likely to experience the Poggendorff illusion effect than patients with isolated cerebral stroke or healthy controls (74.6, 90.5 and 89.8%, respectively; F(2,76) = 6.675, P = 0.002). However, there were no inter-group differences in the control tasks. Lesion-symptom mapping analysis revealed that the brain lesions associated with the reduced frequency of the Poggendorff illusion effect were mainly centred on the right posteromedial cerebellar region, including the right lobules VI, VII, VIII, IX and Crus II. Our findings demonstrated, for the first time, that patients with cerebellar damage were significantly less likely to experience the Poggendorff illusion effect and that right posteromedial cerebellar lesions played an important role in this effect. These results provide new insight into alterations of a geometric illusion effect in patients with cerebellar disorders and pave the way for future clinical use of the illusion task to detect cerebellar abnormalities.

Relationship between motor learning and gambling propensity in Parkinson's disease.

INTRODUCTION: The basal ganglia and related dopaminergic cortical areas are important neural systems underlying motor learning and are also implicated in impulse control disorders (ICDs). Motor learning impairments and ICDs are frequently observed in Parkinson's disease (PD). Nevertheless, the relationship between motor learning ability and ICDs has not been elucidated. METHODS: We examined the relationship between motor learning ability and gambling propensity, a possible symptom for prodromal ICDs, in PD patients. Fifty-nine PD patients without clinical ICDs and 43 normal controls (NC) were administered a visuomotor rotation perturbation task and the Iowa Gambling Task (IGT) to evaluate motor learning ability and gambling propensity, respectively. Participants also performed additional cognitive assessments and underwent brain perfusion SPECT imaging. RESULTS: Better motor learning ability was significantly correlated with lower IGT scores, i.e., higher gambling propensity, in PD patients but not in NC. The higher scores on assessments reflecting prefrontal lobe function and well-preserved blood perfusion in prefrontal areas were correlated with lower IGT scores along with better motor learning ability. CONCLUSIONS: Our findings suggest that better motor learning ability and higher gambling propensity are based on better prefrontal functions, which are in accordance with the theory that the prefrontal cortex is one of the common essential regions for both motor learning and ICDs.

Rapid and comprehensive diagnostic method for repeat expansion diseases using nanopore sequencing.

We developed a diagnostic method for repeat expansion diseases using a long-read sequencer to improve currently available, low throughput diagnostic methods. We employed the real-time target enrichment system of the nanopore GridION sequencer using the adaptive sampling option, in which software-based target assignment is available without prior sample enrichment, and built an analysis pipeline that prioritized the disease-causing loci. Twenty-two patients with various neurological and neuromuscular diseases, including 12 with genetically diagnosed repeat expansion diseases and 10 manifesting cerebellar ataxia, but without genetic diagnosis, were analyzed. We first sequenced the 12 molecularly diagnosed patients and accurately confirmed expanded repeats in all with uniform depth of coverage across the loci. Next, we applied our method and a conventional method to 10 molecularly undiagnosed patients. Our method corrected inaccurate diagnoses of two patients by the conventional method. Our method is superior to conventional diagnostic methods in terms of speed, accuracy, and comprehensiveness.

Case Report: Extremely Early Detection of Preclinical Magnetic Resonance Imaging Abnormality in Creutzfeldt-Jakob Disease With the V180I Mutation.

The diagnosis of presymptomatic Creutzfeldt-Jakob disease (CJD) is challenging. The levels of total tau protein, 14-3-3 protein, and protease-resistant isoform of prion protein (PrPres) in the cerebrospinal fluid; periodic sharp wave complexes on electroencephalography; and diffusion-weighted imaging (DWI) of brain magnetic resonance imaging (MRI) have all been used to diagnose symptomatic CJD, but none of these markers have been established in the diagnosis of presymptomatic CJD. Here, we report a case of genetic CJD with the V180I mutation in which a small punctate cortical hyperintensity was detected on DWI 6 months before symptom onset and 9 months before diagnosis. Presymptomatic CJD is currently impossible to diagnose because of the lack of established early diagnostic markers. However, since MRI is increasingly used in daily clinical practice, the chance detection of such DWI abnormalities would have important implications in terms of providing a clue to examine a highly specific early diagnostic marker to be developed in the future for CJD. This will allow presymptomatic intervention by disease-modifying therapy in the near future.

Neural mechanisms of foreign accent syndrome: Lesion and network analysis.

BACKGROUND: Foreign accent syndrome (FAS) is a rare acquired speech disorder wherein an individual's spoken accent is perceived as "foreign." Most reported cases involve left frontal brain lesions, but it is known that various other lesions can also cause FAS. To determine whether heterogeneous FAS-causing lesions are localized to a common functional speech network rather than to a single anatomical site, we employed a recently validated image analysis technique known as "lesion network mapping." METHODS: We identified 25 published cases of acquired neurogenic FAS without aphasia, and mapped each lesion volume onto a reference brain. We next identified the network of brain regions functionally connected to each FAS lesion using a connectome dataset from normative participants. Network maps were then overlapped to identify common network sites across the lesions. RESULTS: Classical lesion overlap analysis showed heterogeneity in lesion anatomical location, consistent with prior reports. However, at least 80% of lesions showed network overlap in the bilateral lower and middle portions of the precentral gyrus and in the medial frontal cortex. The left lower portion of the precentral gyrus is suggested to be the location of lesions causing apraxia of speech (AOS), and the middle portion is considered to be a larynx-specific motor area associated with the production of vowels and stop/nasal consonants and with the determination of pitch accent. CONCLUSIONS: The lesions that cause FAS are anatomically heterogeneous, but they share a common functional network located in the bilateral posterior region of the frontal lobe. This network specifically includes not only the lower portion of the central gyrus, but also its middle region, which is referred to as the larynx motor cortex and is known to be associated with phonation. Our findings suggest that disrupted networks in FAS might be anatomically different from those in AOS.

Qualitative Deficits in Verbal Fluency in Parkinson's Disease with Mild Cognitive Impairment: A Clinical and Neuroimaging Study.

BACKGROUND: Mild cognitive impairment (MCI) in Parkinson's disease (PD) is considered a risk factor for PD with dementia (PDD). Verbal fluency tasks are widely used to assess executive function in PDD. However, in cases of PD with MCI (PD-MCI), the relative diagnostic accuracy of different qualitative verbal fluency measures and their related neural mechanisms remain unknown. OBJECTIVE: This study aimed to investigate the relative diagnostic accuracy of qualitative (clustering and switching) verbal fluency strategies and their correlates with functional imaging in PD-MCI. METHODS: Forty-five patients with PD (26 with MCI and 19 without MCI) and 25 healthy controls underwent comprehensive neurocognitive testing and resting-state functional magnetic resonance imaging. MCI in patients with PD was diagnosed according to established clinical criteria. The diagnostic accuracy of verbal fluency measures was determined via receiver operating characteristic analysis. Changes in brain functional connectivity between groups and across clinical measures were assessed using seed-to-voxel analyses. RESULTS: Patients with PD-MCI generated fewer words and switched less frequently in semantic and phonemic fluency tasks compared to other groups. Switching in semantic fluency showed high diagnostic accuracy for PD-MCI and was associated with reduced functional connectivity in the salience network. CONCLUSION: Our results indicate that reduced switching in semantic fluency tasks is a sensitive and specific marker for PD-MCI. Qualitative verbal fluency deficits and salience network dysfunction represent early clinical changes observed in PD-MCI.

[A case of cavernous angioma in the lower pons, showing subacute onset of unilateral cranial nerve palsy and segmental sensory disturbance].

We report a 54-year-old man with right abducent nerve palsy, right facial nerve palsy, and left segmental sensory disturbance, which progressed for 2 weeks. He was found to have cavernous angioma in the lower pons. When he visited our hospital, he had right facial palsy, sensory disturbance of left half of the face and left upper limb, and diplopia. He had suffered right abducent nerve palsy 5 years previously and had recently developed hypertension. Neurological examination further revealed right abducent nerve palsy, right peripheral facial nerve palsy, sensory impairment of the left half of the face, and sensory impairment on the left side from C2 to Th3. Magnetic resonance imaging of the head revealed hemorrhage with a rim at the right dorsal part of the lower pons. No abnormalities were identified on cerebral angiography. He was diagnosed as having hemorrhage originating from a cavernous angioma. We assumed that the segmental sensory disturbance was caused by medial involvement of the lateral spinothalamic tract, which is somatotopically arranged: the fibers from the sacral segments being most lateral. The ventral trigeminothalamic tract, right abducent nerve, and right facial nerve were also disturbed. Segmental sensory disturbance usually accompanies a spinal cord lesion. But several cases with similar symptoms following a brainstem lesion have been reported. Most of them had stroke, showing acute onset of illness. Our case showed subacute onset of illness; cranial nerve palsy and segmental sensory disturbance progressed for 2 weeks.

Adjustment of Subthalamic Deep Brain Stimulation Parameters Improves Wheeze and Dyspnea in Parkinson's Disease.

Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment for motor features in Parkinson's disease (PD). We present the case of a 56-year-old man with a 17-year history of PD. He underwent bilateral STN-DBS at the age of 51 years because of troublesome dyskinesia and wearing off. His motor features dramatically improved after the operation; however, he developed dysarthria and a refractory wheeze associated with dyspnea due to abnormal hyperadduction of the false vocal fold. By adjusting the stimulation site of STN, his severe wheeze, which was considered to be the result of the unfavorable spread of current to the corticobulbar tract, was significantly improved. This report provides concrete evidence that wheezing is caused by hyperadduction of the false vocal fold as an adverse effect of STN-DBS and can be reversed by adjusting the stimulation site for STN-DBS.

[Anti-MuSK antibody positive myasthenia gravis with HIV infection successfully treated with cyclosporin: a case report].

A-58-year old man presented with fluctuating ptosis and dysphagia. When he was 53 years old, he developed oral candidiasis and serum human immunodeficiency virus (HIV) RNA was detected. After starting highly active antiretroviral therapy, serum HIV RNA became undetectable. Neurological examination revealed ptosis and bulbar symptoms. Myasthenia gravis was comfirmed by a positive edrophonium test, showing 20% decrement of the compound muscle action potential on repetitive stimulation. Anti-acetylcholine receptor antibodies were negative and anti-muscle specific tyrosine kinase (MuSK) antibodies were positive. The chest CT scan was normal. He experienced transient clinical remission with pyridostigmine bromide and prednisolone. However relapse occurred after he returned to work. Persistent clinical remission was first observed after cyclosporin administration. There are eleven reports in which patients had concomitant myasthenia gravis and HIV infection. Most of those cases were benign in clinical course and required only anticholinesterase therapy. In our case, however, anti-MuSK antibodies were positive, and symptoms of myasthenia gravis remained despite prednisolone administration. Cyclosporin is directly active against HIV, and thus, cyclosporine therapy may be helpful in patients with concomitant myasthenia gravis and HIV infection.

White matter hyperintensities on MRI in dementia with Lewy bodies, Parkinson's disease with dementia, and Alzheimer's disease.

BACKGROUND: In dementia with Lewy bodies (DLB) and Parkinson's disease with dementia (PDD), it is still debated whether white matter hyperintensities (WMH) on MRI reflect atherosclerotic cerebrovascular changes or Alzheimer's disease (AD)-related pathology such as cerebral amyloid angiopathy. To examine AD-related pathology in DLB and PDD, we compared the severity of WMH and medial temporal lobe atrophy among patients with DLB, PDD, non-demented PD (PDND), and AD. METHODS: We retrospectively studied sex- and age-matched outpatients with AD, DLB, PDD, and PDND, as well as subjects without central nervous system disorders as normal controls (n=50 each). All subjects underwent 1.5-T MRI examinations, and WMH detected by T2-weighted images or fluid-attenuated inversion recovery images were semiquantified according to the Fazekas method. Medial temporal lobe atrophy (MTA) was visually assessed by the MTA score. RESULTS: WMH were more prominent in AD, DLB, and PDD patients than in PDND patients and normal controls (NCs). DLB as well as AD showed more severe WMH than PDD. Visual assessment of medial temporal lobe atrophy showed that AD patients had the most severe atrophy, followed by DLB, PDD, and PDND patients, and NC subjects in that order. MTA scores showed significant correlations with WMH severity. CONCLUSION: Our results indicated that DLB was more similar to AD than to PDD in terms of MRI findings, suggesting that WMH in DLB may reflect mainly AD-related pathology rather than atherosclerotic cerebrovascular changes.

[Distigmine bromide improves chronic intestinal pseudo-obstruction in a case of MELAS].

A 34-year-old man with MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes) showed chronic intestinal pseudo-obstruction (CIPO), which was improved by the administration of distigmine bromide. He exhibited generalized tonic clonic seizures at the age of 21, and mitochondrial DNA analysis showed the MELAS mutation. At the age of 34, he became akinetic mutism after nonconvulsive status epilepticus and needed enteral nutrition through a nasogasrtic tube. However, he developed abdominal distention and vomiting, and was diagnosed as CIPO, therefore tube feeding was stopped. Although the administration of domperidone, mosapride citrate, butyric acid bacteria, sodium picosulfate, prostaglandin F2 alpha, pantothenic acid, dioctyl sodium sulfosuccinate, and so on, was ineffective, the administration of distigmine bromide improved his bowel motion disturbance and abnormal distention. The present case is the first MELAS patient with CIPO to be ameliorated by distigmine bromide, which might work acetylcholine receptor on the interstitial cells of Cajal.