Dystonia and Parkinsonism in COA7-related disorders: expanding the phenotypic spectrum.

BACKGROUND AND OBJECTIVE: Biallelic mutations in the COA7 gene have been associated with spinocerebellar ataxia with axonal neuropathy type 3 (SCAN3), and a notable clinical diversity has been observed. We aim to identify the genetic and phenotypic spectrum of COA7-related disorders. METHODS: We conducted comprehensive genetic analyses on the COA7 gene within a large group of Japanese patients clinically diagnosed with inherited peripheral neuropathy or cerebellar ataxia. RESULTS: In addition to our original report, which involved four patients until 2018, we identified biallelic variants of the COA7 gene in another three unrelated patients, and the variants were c.17A > G (p.D6G), c.115C > T (p.R39W), and c.449G > A (p.C150Y; novel). Patient 1 presented with an infantile-onset generalized dystonia without cerebellar ataxia. Despite experiencing an initial transient positive response to levodopa and deep brain stimulation, he became bedridden by the age of 19. Patient 2 presented with cerebellar ataxia, neuropathy, as well as parkinsonism, and showed a slight improvement upon levodopa administration. Dopamine transporter SPECT showed decreased uptake in the bilateral putamen in both patients. Patient 3 exhibited severe muscle weakness, respiratory failure, and feeding difficulties. A haplotype analysis of the mutation hotspot in Japan, c.17A > G (p.D6G), uncovered a common haplotype block. CONCLUSION: COA7-related disorders typically encompass a spectrum of conditions characterized by a variety of major (cerebellar ataxia and axonal polyneuropathy) and minor (leukoencephalopathy, dystonia, and parkinsonism) symptoms, but may also display a dystonia-predominant phenotype. We propose that COA7 should be considered as a new causative gene for infancy-onset generalized dystonia, and COA7 gene screening is recommended for patients with unexplained dysfunctions of the central and peripheral nervous systems.

Seronegative neuromyelitis optica spectrum disorder in primary familial brain calcification with PDGFB variant.

•This case indicates that the PDGFB variant is associated with PFBC as well as with NMOSD.

Bromisoval-induced bromism with status epilepticus mimicking Wernicke's encephalopathy: report of two cases.

BACKGROUND: Bromine compounds are used in several drugs, including over-the-counter drugs. They sometimes cause intoxication known as bromism. Although the acute neurological symptoms and sequelae of bromism vary, few reports have mentioned acute encephalopathy. CASE PRESENTATION: We report two cases of bromisoval-induced bromism with status epilepticus. Presence of pseudohyperchloremia and history of over-the-counter medication use guided the diagnosis. In the acute phase, our patients showed bilateral medial thalamic lesions on magnetic resonance imaging. The imaging findings were similar to those of Wernicke's encephalopathy. Although these findings improved in the chronic phase, neuropsychiatric sequelae, such as confabulation and amnesia, occurred. CONCLUSION: Bromism can cause acute encephalopathy, and it is important to differentiate it from Wernicke-Korsakoff syndrome.

Erythroblast appearance associated with natalizumab.

Despite having a high rate of occurrence, erythroblast appearance in peripheral blood may not be a recognized adverse effect of natalizumab (NTZ) treatment. Additionally, the time course and cause of erythroblast appearance remain unclear. We report two cases of multiple sclerosis wherein NTZ treatment led to erythroblast appearance in peripheral blood. Erythroblasts appeared after NTZ administration; however, their counts did not increase and the administration of medication was continued. NTZ can inhibit erythroblastic island formation associated with maturing of erythroblast via VLA-4. Clinicians do not need to be afraid; however, careful observation is recommended because some patients may develop anemia.

Acute necrotizing encephalopathy and a carnitine palmitoyltransferase 2 variant in an adult.

A 54-year-old Japanese man had a fever of over 40 °C for 7 days and developed unconsciousness, seizure and respiratory arrest. T2-weighted imaging magnetic resonance imaging revealed high-intensity signals on bilateral thalamus and it gradually extended to the brain white matter. Moreover, the lesion progressed to the spinal gray matter. The patient was diagnosed with acute necrotizing encephalopathy. CPT2 variants have been reported to be associated with acute necrotizing encephalopathy particularly in children and spinal cord lesions are extremely rare. We report a case of ANE in an adult with a CPT2 variant who developed spinal cord lesions.

A Japanese Family of Spinocerebellar Ataxia Type 21: Clinical and Neuropathological Studies.

Spinocerebellar ataxia type 21 (SCA21) is a rare subtype of autosomal dominant cerebellar ataxias, which was first identified in a French family and has been reported almost exclusively in French ancestry so far. We here report the first Japanese family with SCA21, in which all affected members examined carried a heterozygous c.509C > T:p.Pro170Leu variant in TMEM240. Their clinical features were summarized as a slowly progressive ataxia of young-adult onset (5-48 years) associated with various degree of psychomotor retardation or cognitive impairment. The MR images revealed atrophy in the cerebellum, but not in the cerebrum or brainstem. These clinical findings were consistent with those in the original French families with SCA21. Neuropathological findings in one autopsied patient showed a prominent decrease of cerebellar Purkinje cells, but no specific abnormalities outside the cerebellum.

Left Upper Lung Lobectomy Is an Embolic Risk Factor for Cerebral Infarction.

Cerebral embolism is typically caused by a cardiogenic thrombus. The patent foramen ovale is a well-known cause of paradoxical embolism. However, some idiopathic cases of stroke have been reported. Such strokes are designated as embolic stroke of undetermined sources. Among them, lung lobectomy may be a new embolic risk factor for cerebral embolism. The risk of thrombus formation is high at the pulmonary vein stump after lung lobectomy, especially in the left upper lobe. Interestingly, the risk remains several years after surgery. This condition is mostly overlooked, and reported cases of this condition are rare. Methods of early detection, prevention, and treatment have not been established. Here we report the case of a 66-year-old man who suffered a cerebral infarction 2 days after left upper lobectomy. Three-dimensional computed tomography scan clearly revealed the structural feature of the pulmonary vein stump. The stump of patients with cerebral infarction after lung lobectomy should be checked.

MTCL1 plays an essential role in maintaining Purkinje neuron axon initial segment.

The axon initial segment (AIS) is a specialized domain essential for neuronal function, the formation of which begins with localization of an ankyrin-G (AnkG) scaffold. However, the mechanism directing and maintaining AnkG localization is largely unknown. In this study, we demonstrate that in vivo knockdown of microtubule cross-linking factor 1 (MTCL1) in cerebellar Purkinje cells causes loss of axonal polarity coupled with AnkG mislocalization. MTCL1 lacking MT-stabilizing activity failed to restore these defects, and stable MT bundles spanning the AIS were disorganized in knockdown cells. Interestingly, during early postnatal development, colocalization of MTCL1 with these stable MT bundles was observed prominently in the axon hillock and proximal axon. These results indicate that MTCL1-mediated formation of stable MT bundles is crucial for maintenance of AnkG localization. We also demonstrate that Mtcl1 gene disruption results in abnormal motor coordination with Purkinje cell degeneration, and provide evidence suggesting possible involvement of MTCL1 dysfunction in the pathogenesis of spinocerebellar ataxia.

Missing genetic variations in GNE myopathy: rearrangement hotspots encompassing 5'UTR and founder allele.

GNE myopathy is an autosomal recessive distal myopathy caused by loss-of-function mutations in the GNE gene, which encodes UDP-GlcNAc 2-epimerase/ManNAc kinase (GNE), a key enzyme in sialic-acid biosynthesis. By comprehensive screening of manifesting patients using a fine-mapped targeted next-generation sequencing (NGS), we identified copy number variations (CNVs) in 13 patients from 11 unrelated families. The nine unique CNVs largely vary in size from 0.3 to 72 kb. Over half of the cases carry different deletions spanning merely exon 2, which contains the 5' untranslated region (5'UTR) of the muscle major transcript hGNE1. Of most unique CNVs, either the telomeric or the centromeric breakpoint locates within intron 2, indicating rearrangement hotspots. Haplotype analysis suggested the existence of a founder allele with exon 2 deletion. The breakpoints for all CNVs were determined by long-range PCR and sequencing. All of the breakpoints of gross deletion/duplications reside within directly oriented pairs of Alu repeats. The results of this study firstly widen the spectra of mutations to CNVs encompassing 5'UTR, underscoring the pivotal role of the hGNE1 transcript. Alu-mediated non-recurrent CNVs may have been overlooked in a wide variety of recessive phenotypes, especially in those associated with genomic Alu-rich genes such as GNE.

Natural History of Spinocerebellar Ataxia Type 31: a 4-Year Prospective Study.

Spinocerebellar ataxia type 31 (SCA31) is known as a late-onset, relatively pure cerebellar form of ataxia, but a longitudinal prospective study on the natural history of SCA31 has not been done yet. In this prospective cohort study, we enrolled 44 patients (mean ± standard deviation 73.6 ± 8.5 years) with genetically confirmed SCA31 from 10 ataxia referral centers in the Nagano area, Japan. Patients were evaluated every year for 4 years using the Scale for the Assessment and Rating of Ataxia (SARA) and the Barthel Index (BI). Of the 176 follow-up visits (91.5%), 161 were completed in this study. Five patients (11.4%) died during the follow-up period, and two patients (4.5%) were lost to follow-up. The annual progression of the SARA score was 0.8 ± 0.1 points/year and that of the BI was -2.3 ± 0.4 points/year (mean ± standard error). Shorter disease duration at baseline was associated with faster progression of the SARA score. Our study indicated the averaged clinical course of SCA31 as follows: the patients develop ataxic symptoms at 58.5 ± 10.3 years, become wheelchair bound at 79.4 ± 1.7 years, and died at 88.5 ± 0.7 years. Our prospective dataset provides important information for clinical trials of forthcoming disease-modifying therapies for cerebellar ataxia. It also represents a useful resource for SCA31 patients and their family members in genetic counseling sessions.

Cerebral amyloid angiopathy in posttransplant patients with hereditary ATTR amyloidosis.

OBJECTIVE: To investigate the prevalence and clinical features of posttransplant CNS symptoms in patients with hereditary ATTR amyloidosis and their Pittsburgh compound B (PiB)-PET imaging correlates. METHODS: We monitored prevalence and type of CNS symptoms in 53 consecutive posttransplant patients with hereditary ATTR amyloidosis. (11)C-PiB-PET was performed in 15 patients with various disease durations. We also analyzed pathologic and biochemical characteristics of ATTR amyloid deposition in the brain of a posttransplant patient. RESULTS: Transient focal neurologic episodes (TFNEs) attributed to ATTR-type cerebral amyloid angiopathy (CAA) were found in 11.3% of posttransplant hereditary ATTR amyloidosis patients. TFNE occurred on average 16.8 years after onset of the disease. Patients with longer duration of illness (≥10 years) showed increased (11)C-PiB retention in the brain. The (11)C-PiB accumulation pattern in hereditary ATTR amyloidosis was unique and different from those in Alzheimer disease or Aß-type CAA. In the autopsy case, ATTR amyloid deposition was mainly localized to leptomeningeal vessels and leptomeninges of the brain. Amyloid fibrils in the brain were almost completely composed of variant transthyretin (TTR). CONCLUSIONS: TFNE due to ATTR-type CAA occurred frequently in posttransplant patients with long disease durations. (11)C-PiB-PET is a useful diagnostic tool for ATTR-type CAA. ATTR amyloid deposition in the CNS, as measured by PiB-PET, was detected approximately 10 years before onset of TFNE.

Clinical Phenotype and Segregation of Mitochondrial 3243A>G Mutation in 2 Pairs of Monozygotic Twins.

IMPORTANCE: The regulatory factors explaining the wide spectrum of clinical phenotypes for mitochondrial 3243A>G mutation are not known. Crosstalk between nuclear genes and mitochondrial DNA might be one factor. OBSERVATIONS: In this case series, we compared 2 pairs of male twins with the mitochondrial 3243 A>G mutation and mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes syndrome with a female control patient. One pair of monozygotic twins presented with diabetes and deafness in their 30s, stroke-like episodes in their 40s, and cardiac events and death in their 50s. Another pair of twins presented with deafness and stroke-like episodes in their 20s. The degree of heteroplasmy of 3243A>G mutation in the various tissues and organs was similar in the first pair of twins compared with the control patient. CONCLUSIONS AND RELEVANCE: The clinical phenotype and segregation of mitochondrial 3243A>G mutation was similar in monozygotic twins. The onset age and distribution of the symptoms might be regulated by nuclear genes. Our findings might help to predict the clinical course of the surviving twins and afford an opportunity for therapy before the onset of mitochondrial disease, especially for monozygotic twins caused by nuclear transfer with a small amount of nuclear-donor mitochondrial DNA.

Predominant cerebellar phenotype in spastic paraplegia 7 (SPG7).

We report a Japanese family with spastic paraplegia 7 (SPG7) that carries a deleterious homozygous p.R398X mutation in SPG7. The patients showed a predominant cerebellar ataxia phenotype. SPG7 is quite rare in Japan, but it should be included in the differential diagnosis for hereditary spastic-ataxic syndromes, even if the cerebellar signs are much more pronounced than the pyramidal tract signs.

[A case of colchicine-responsive Mollaret's meningitis with MEFV gene mutation].

A 66-year-old woman was admitted to our hospital with recurrent meningitis. She presented with 10 episodes of meningitis in 10 months. Examination of cerebrospinal fluid demonstrated pleocytosis, with neutrophils dominant at the early stage, and lymphocytes dominant at the late stage. Mollaret cells were found and the level of IL-6 was increased in cerebrospinal fluid. Several antibiotics and antiviral agents failed to prevent relapse. However, colchicine therapy successfully prevented the recurrence of meningitis. Genetic testing for familial Mediterranean fever (FMF) showed a mutation in the MEFV gene. It is difficult to diagnose the cause of Mollaret's meningitis in some patients. FMF, neuro-Behçet's disease, and neuro-Sweet disease should be included in the differential diagnosis of recurrent meningitis. In addition, colchicine therapy can prevent the relapse of meningitis in such cases.

[An autopsied case of postinfectious neuromyelitis optica in an 84-year-old man].

An 84-year-old man presented with acute bilateral visual impairment 2 weeks after an upper respiratory tract infection. A few days later, he developed left hemiparesis, followed by paraplegia. The brain magnetic resonance imaging (MRI) showed high-intensity lesions in the right cerebellum, pons, left and right corona radiata, and right putamen. The diffusion weighted image also showed these high-intensity lesions. The spinal MRI showed an edematous, longitudinally extensive, cord lesion at the C5-Th6 level of the spine. Intravenous corticosteroid therapy was initiated, but the patient showed mild improvement. Although methylprednisolone pulse therapy was administered 5 times, he continued to present with clinical relapse and died on day 50. Anti-aquaporin-4 (AQP4) antibodies were detected in the patient's serum. Autopsy findings showed necrotic lesions at the spinal cord, brain, and optic chiasma and nerves. An immunohistopathological study showed the loss of AQP4- and glial fibrillary acidic protein (GFAP)-positive cells, with relatively preserved myelin basic protein (MBP)-positive myelin in the necrotic lesions. We diagnosed the patient as having neuromyelitis optica (NMO) because of the seropositivity for anti-AQP4 antibodies and on the basis of above-mentioned other immunohistochemical findings. It is difficult to distinguish NMO from ADEM clinically, when the patient has a preceding infection. NMO should be considered in patients with multifocal lesions in the central nervous system who have prominent myelitis and optic neuritis, irrespective of the postinfectious onset of the lesions and the sex and age of the patient.

[A clinically diagnosed lymphocytic hypophysitis presenting as recurrent meningitis].

A 55-year-old woman was admitted to our hospital complaining of severe headache with fever and apparent neck stiffness. Neutrophilic pleocytosis was demonstrated in cerebrospinal fluid (CSF) and bacterial meningitis was strongly suspected, but bacterial culture of CSF was negative. After the symptoms normalized within a few days, she developed diabetes insipidus and gadolinium (Gd)-enhancement of the enlarged hypophysis and stalk was observed on cranial MRI. A Lymphocytic Hypophysitis (LH) was clinically diagnosed. Follow-up studies demonstrated spontaneous remission of serological, radiological, and CSF findings, and she was discharged on hormonal replacement therapy with desmopressin. Three months later, she returned to our hospital complaining of headache again under adenohypophysial hypofunction and expanding pituitary lesion on MRI. CSF analysis showed meningitis but there was no evidence of infection by microorganisms. Our diagnosis was relapsing LH with aseptic meningitis, and the patient was administered methylprednisolone pulse therapy, which induced rapid improvement in clinical, endocrinological, and radiological findings. This case showed a possible unique clinical presentation of LH characterized as recurrent aseptic meningitis. It is important to recognize this phenotype of LH, and to prescribe corticosteroid therapy after appropriate endocrinological and radiological studies.

Congenital fibrosis of the extraocular muscles (CFEOM) syndrome associated with progressive cerebellar ataxia.

We here report on a Japanese family with congenital fibrosis of the extraocular muscles (CFEOM) syndrome associated with slowly progressive cerebellar ataxia. The pedigree indicated autosomal dominant inheritance. All affected individuals showed a complete loss of upgaze function with ptosis, and severe or moderate restriction of downgaze function probably from the birth. Horizontal gaze function was well preserved, except for the eldest patient, who showed both eyes almost totally fixed in exotrophic position. The primary vertical and horizontal position of each eye varied from patient to patient. Aberrant eye movements were observed on attempted upgaze. They showed amblyopia and/or astigmatism, but none of them complained of diplopia. Pupillary reactions were normal, and retinal pigmentary degeneration or optic atrophy was not observed. These ophthalmological findings were consistent with the CFEOM phenotype. The two middle-aged patients, but not the two younger patients, showed slowly progressive gait ataxia with juvenile onset. Magnetic resonance images of the brain indicated cerebellar atrophy in addition to congenital hypoplasia in the cerebellar vermis. Molecular genetic analysis provided a negative linkage to the FEOM3 locus. Linkage to the FEOM1 locus could not be excluded in our family, but mutation in KIF21A, a major cause of the CFEOM1 phenotype, was not detected. We consider that this family may broaden the spectrum of the clinical features of CFEOM or the related disorders presenting with the CFEOM phenotype.