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

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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.

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.

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 Aβ-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.

Axonal TDP-43 aggregates in sporadic amyotrophic lateral sclerosis

AIMS

Axonal aggregates of phosphorylated (p-) transactive response DNA-binding protein 43 kDa (TDP-43) in sporadic amyotrophic lateral sclerosis (sALS) were examined in relation to propagation of the protein in the nervous system.

METHODS

Brains and spinal cords of Japanese patients with sALS and control subjects were examined immunohistochemically using formalin-fixed paraffin-embedded specimens with special reference to the topographical distribution, microscopic features, presynaptic aggregates, and correlation between the aggregates in axons and the clinical course.

RESULTS

(i) Aggregates of p-TDP-43 were frequently present in axons of the hypoglossal and facial nerve fibres and the spinal anterior horn cells. (ii) Aggregates of p-TDP-43 in the axons showed two characteristic microscopic features - dash-like granuloreticular aggregates (GRAs) and massive aggregates (MAs). (iii) MAs were surrounded by p-neurofilaments, but p-neurofilament immunnoreactivity decreased at the inside of axons with GRAs. (iv) Patients showing MAs and GRAs had a relatively shorter clinical course than patients without the aggregates. (v) Some neurones in the red nucleus in patients were surrounded by synapses containing p- and p-independent (i)-TDP-43, and almost all neurones had lost their nuclear TDP-43 immunoreactivity; 17% of those neurones in the red nucleus also had TDP-43-immunopositive neuronal cytoplasmic inclusions, but no postsynaptic p-TDP-43 deposition was evident.

CONCLUSIONS

There are two types of axonal p-TDP-43 aggregates, MAs and GRAs, located predominantly in the facial and hypoglossal nuclei and anterior horn cells. These aggregates may influence the function of neurones, and presynaptic aggregates of the protein induce loss of p-i-TDP-43 in the nuclei of postsynaptic neurones.

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.

Castration of male C57L/J mice increases susceptibility and estrogen treatment restores resistance to Theiler's virus-induced demyelinating disease

Intracerebral inoculation of Theiler's murine encephalomyelitis virus (TMEV) results in immune-mediated demyelination in selective mouse strains. We have previously demonstrated that the males of C57L mice are significantly more susceptible to TMEV-induced demyelinating disease. To assess further the hormonal influence for this gender-associated differential susceptibility, estrogen-treated, castrated C57L mice were infected with TMEV and compared with sham-operated and/or placebo-treated mice. Interestingly, castration further elevated the susceptibility to virally induced demyelinating disease compared with sham-castrated control mice, and prolonged treatment of castrated mice with estrogen restored the resistance to the level of control mice. These results strongly suggest that sex hormone levels contribute to the gender-biased susceptibility to TMEV-induced demyelinating disease. Mice treated with estrogen showed a significantly decreased level of virus-specific Th1 responses both in the periphery and in the CNS. In addition, in vitro estrogen treatment was able to inhibit viral replication directly in macrophages, consistent with the lower level of viral RNA in microglia/macrophages in the CNS from castrated estrogen-treated mice compared with controls. Also, estrogen treatment inhibited VCAM-1 expression induced by tumor necrosis factor-alpha in cerebral vascular endothelial (CVE) cells via inhibition of nuclear factor-kappaB (NFkappaB), which is produced in various glial cells upon TMEV infection. Overall, estrogen treatment appears to exert its effects on viral replication, induction of immune responses, as well as infiltration of activated immune cells into the CNS via inhibition of NFkappaB function.

Oral administration of live virus protects susceptible mice from developing Theiler's virus-induced demyelinating disease

Intracerebral infection of susceptible mouse strains with Theiler's murine encephalomyelitis virus (TMEV) results in an immune-mediated demyelinating disease similar to human multiple sclerosis. TMEV infection is widely spread via fecal-oral routes among wild mouse populations, yet these infected mice rarely develop clinical disease. Oral vaccination has often been used to protect the host against many different infectious agents, although the underlying protective mechanism of prior oral exposure is still unknown. To understand the mechanisms involved in protection from demyelinating disease following previous oral infection, immune parameters and disease progression of mice perorally infected with TMEV were compared with those of mice immunized intraperitoneally following intracerebral infection. Mice infected perorally, but not intraperitoneally, prior to CNS viral infection showed lower chronic viral persistence in the CNS and reduced TMEV-induced demyelinating disease. However, a prolonged period of post-oral infection was necessary for effective protection. Mice orally pre-exposed to the virus displayed markedly elevated levels of antibody response to TMEV in the serum, although T cell responses to TMEV in the periphery were not significantly different between perorally and intraperitoneally immunized mice. In addition, orally vaccinated mice showed higher levels of early CNS-infiltration of B cells producing anti-TMEV antibody as well as virus-specific CD4(+) and CD8(+) T cells in the CNS compared to intraperitoneally immunized mice. Therefore, the generation of a sufficient level of protective immune responses appears to require a prolonged time period to confer protection from TMEV-induced demyelinating disease.

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.

Increase in incidence of elderly-onset patients with myasthenia gravis in Nagano Prefecture, Japan

OBJECTIVES

In European countries and the United States the incidence of elderly-onset myasthenia gravis (MG) has recently been increasing. To investigate whether the incidence of the elderly-onset MG has increased in Nagano Prefecture of Japan, we divided the patients into young and elderly groups, and retrospectively examined their incidence.

PATIENTS AND METHODS

On the basis of two-step questionnaires sent to hospitals and the patient list of the intractable disease registration system in Nagano Prefecture we studied 213 MG patients diagnosed between 1982 and 2001. This 20-year period was divided into 4 five-year terms, and the incidence of MG in young- (younger than 65) and elderly-onset (65 or older) groups was investigated separately for each term.

RESULTS

The ratio of the elderly-onset group showed a significantly positive correlation with terms irrespective of associated thymoma (r=0.98, p<0.05). There was a significant difference in the mean onset age among the 4 terms (p<0.005). The standardized incidence of MG gradually increased in both young- and elderly-onset groups as well as in the whole age range. The elderly group showed a particularly high incidence in females (12.01/million/year) and in patients without thymoma (8.78/million/year) in the final five years.

CONCLUSIONS

We confirmed that the incidence of elderly-onset MG has recently been increasing in the Nagano Prefecture. Since the change of the age distribution in this district is almost identical to that of the whole country, the incidence of MG might have been increasing in Japan as a whole, particularly in the elderly population.

Intravascular large B cell lymphoma diagnosed by senile angioma biopsy

An 82-year-old man without notable medical history was admitted to our hospital following subacute deterioration of apettite, disorientation and strange behavior. There was spasticity of the right extremities without weakness. LDH and serum soluble IL2 receptor antibody levels were elevated, and as well as the protein level and IgG levels in the cerebrospinal fluid. CT scanning of the brain revealed a lesion at the left corona radiata. The patient's level of consciousness was worsening, and follow-up study of the brain showed a new lesion in the left occipital lobe. Intravascular lymphomatosis was therefore suspected. We performed a skin biopsy from two typical senile angiomas. In one of these biopsy specimens, a capillary hemangioma was present in the mid-reticular dermis and it was filled with abnormal B cells. The diagnosis of intravascular B cell lymphoma (IVL) was thus established. IVL is a rare subtype of extranodal diffuse large B cell lymphoma with a poor outcome. However, it is recently thought that if the diagnosis is established early, aggressive chemotherapy increases survival. Senile angioma is a skin eruption that is considered prevalent for the most part in elderly people. If a patient is suspected to have IVL, and there is no appropriate site of biopsy, it might be beneficial to try a skin biopsy aiming at senile angiomas for early diagnosis.

Serological evidence that Mus musculus is the natural host of Theiler's murine encephalomyelitis virus

Theiler's murine encephalomyelitis virus (TMEV) infection is maintained in mouse colonies by fecal-oral spread (with no apparent role for persistent central nervous system infection) from an acutely infected animal to another. Therefore, serological methods offer the principal way to assess infection in mice and related rodent populations. Infection of mouse colonies with TMEV appears to be worldwide, yet no systematic serologic studies have been reported. In this study, enzyme-linked immunoassay and neutralization analysis of sera from feral Mus musculus obtained from four locations in the United States and one in Russia revealed antibodies to purified TMEV and two linear viral peptide epitopes in more than 50% of the sera derived from the five different locations. A similar analysis of sera from 26 species of related rodents trapped at multiple locations in North America and Europe indicated the presence of anti-TMEV antibodies only in a small proportion of water and bank voles that belong to a different subfamily. These results indicate that Mus musculus is the natural host of TMEV.

Recurrent steroid-responsive trismus and painful ophthalmoplegia

A 63-year-old woman experienced two episodes of trismus and painful ophthalmoplegia at an interval of six years. She suffered left visual loss, and enhanced CT scan and MR imaging revealed heterogeneous enlargement of the left extraocular muscles extending to the orbital apex. In addition, the left pterygopalatine fossa was filled with a mass isointense with muscle without evidence of surrounding tissue invasion; 67Ga scintigraphy showed high uptake in this lesion. Steroid administration dramatically resolved the trismus, and the mass in the orbit and extraorbit vanished completely. Orbital pseudotumor is characterized by self-limited, relapsing, steroid-responsive painful ophthalmoplegia, and this case could be a variant of this entity with inflammation extending into the extraorbital area.

Persistent hemiballism with striatal hyperintensity on T1-weighted MRI in a diabetic patient: a 6-year follow-up study

The combination of hemiballism, hyperglycemia and hyperintensity of the striatum on T1-weighted MRI constitutes a unique syndrome. We report the follow-up of a patient with this disorder whose hemiballism was sustained for over 5 years. High density on CT of the right striatum turned into normodensity in 4 months, and hyperintensity on T1-weighted MRI and hypointensity on T2-weighted MRI of the lesion were resolved in 18 months. A decreased perfusion of the lesion by SPECT remained 37 months after onset. There was no volume change of the lesion during the course of the illness. The radiological features support the possible pathology of either or both petechial hemorrhage and astrocytosis with high protein concentration after ischemic insult. The hemiballism may result from selective damage of GABA/enkephalin-containing neurons in the striatum and can persist without the primary histological changes causing the striatal T1-hyperintensity in this disorder.

[Two cases with chronic inflammatory demyelinating polyneuropathy showing high signal and enlargement of the brachial plexus in short TI inversion recovery of MRI]

We reported valuable MRI findings of the brachial plexus seen in two cases with chronic inflammatory demyelinating polyneuropathy (CIDP). Case 1 was a 44-year-old man who developed slowly progressive weakness and atrophy of the extremities with no sensory disturbances. Studies of CSF showed a normal level of protein and no increase of cell counts but nerve conduction studies demonstrated a significant conduction block between the axilla and the elbow in the right ulnar nerve. Case 2 was a 34-year-old male who had been suffering from distal limb weakness and sensory disturbance. Protein content in CSF was markedly elevated without pleocytosis, and nerve conduction studies revealed a conduction block between the elbow and the wrist in the right ulnar nerve. He received corticosteroid therapy, resulting in a good recovery. Brachial plexus in both cases showed enlargement with marked high signal on short TI inversion recovery (STIR) of MRI. STIR is a fat suppressed T2 weighted image and this technique is known to be useful to identify the morphology of peripheral nerve tissues. CIDP is one form of hypertrophic neuritis and the MRI findings seen in these two cases strongly support the diagnosis of CIDP.

Suppressive effect on Theiler's murine encephalomyelitis virus-induced demyelinating disease by the administration of anti-IL-12 antibody

We examined the role of IL-12, a cytokine critical to the evolution of cellular responses, in the development of Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD). Treatment with mAbs to IL-12, especially during the effector phase, resulted in significant suppression of the development of this disease both clinically and histologically. In mice treated with these mAbs, the production of inflammatory and Th1-derived cytokines such as TNF-alpha and IFN-gamma in the spleen cells was decreased, and that of Th2-derived cytokines such as IL-4 and IL-10 was increased. The delayed type hypersensitivity and T cell proliferative response specific for TMEV were decreased by this treatment. These data suggest that IL-12 is critically involved in the pathogenesis of TMEV-IDD and that Abs to IL-12 could be a novel therapeutic approach in the clinical treatment of demyelinating diseases such as human multiple sclerosis.

Suppressive Effect on Theiler’s Murine Encephalomyelitis Virus-Induced Demyelinating Disease by the Administration of Anti-IL-12 Antibody

We examined the role of IL-12, a cytokine critical to the evolution of cellular responses, in the development of Theiler’s murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD). Treatment with mAbs to IL-12, especially during the effector phase, resulted in significant suppression of the development of this disease both clinically and histologically. In mice treated with these mAbs, the production of inflammatory and Th1-derived cytokines such as TNF-α and IFN-γ in the spleen cells was decreased, and that of Th2-derived cytokines such as IL-4 and IL-10 was increased. The delayed type hypersensitivity and T cell proliferative response specific for TMEV were decreased by this treatment. These data suggest that IL-12 is critically involved in the pathogenesis of TMEV-IDD and that Abs to IL-12 could be a novel therapeutic approach in the clinical treatment of demyelinating diseases such as human multiple sclerosis.

Role of individual T-cell epitopes of Theiler's virus in the pathogenesis of demyelination correlates with the ability to induce a Th1 response

Intracerebral inoculation of susceptible strains of mice with Theiler's murine encephalomyelitis virus (TMEV) results in immune-mediated demyelination. Three major T-cell epitopes have previously been identified within the VP1 (VP1233-250), VP2 (VP274-86), and VP3 (VP324-37) capsid proteins in virus-infected SJL/J mice. These epitopes appear to account for the majority ( approximately 90%) of major histocompatibility complex class II-restricted T-cell responses to TMEV. Interestingly, the effect of immunization with synthetic peptides bearing the predominant T-cell epitopes on the course of TMEV-induced demyelination indicates that T cells reactive to the VP1 and VP2 epitopes, but not VP3, accelerate the pathogenesis of demyelination. The predominant pathogenic role of the T cells is verified by similar immunization with the fusion proteins containing the entire individual capsid proteins. The order of appearance and level of T cells specific for the individual epitopes during the course of demyelination are similar to each other. However, cytokine profiles of T cells from virus-infected mice indicate that T cells specific for the VP1 (and perhaps the VP2) epitope are Th1, whereas T cells reactive to VP3 are primarily Th2. These results suggest that Th1-type cells specific for VP1 and VP2 are involved in the pathogenesis of viral demyelination induced by TMEV. Thus, a predominance of Th1-inducing viral epitopes is likely critical for the pathogenesis of demyelination.

Major linear antibody epitopes and capsid proteins differentially induce protective immunity against Theiler's virus-induced demyelinating disease

Theiler's murine encephalomyelitis virus-induced immunologically mediated demyelinating disease (TMEV-IDD) in susceptible mice provides a relevant infectious model for multiple sclerosis. Previously, we have identified six major linear antibody epitopes on the viral capsid proteins. In this study, we utilized fusion proteins containing individual capsid proteins and synthetic peptides containing the linear antibody epitopes to determine the potential role of antibody response in the course of virus-induced demyelination. Preimmunization of susceptible mice with VPI and VP2 fusion proteins, but not VP3, resulted in the protection from subsequent development of TMEV-IDD. Mice free of clinical symptoms following preimmunizations with fusion proteins displayed high levels of antibodies to the capsid proteins corresponding to the immunogens. In contrast, the level of antibodies to a particular linear epitope, A1C (VP1(262-276)), capable of efficiently neutralizing virus in vitro increased with the progression of disease. Further immunization with synthetic peptides containing individual antibody epitopes indicated that antibodies to the epitopes are differentially effective in protecting from virus-induced demyelination. Taken together, these results suggest that antibodies to only certain linear epitopes are protective and such protection may be restricted during the early stages of viral infection.

Ictal muscle discharge pattern and SPECT in paroxysmal kinesigenic choreoathetosis

We studied the pattern of muscle activity of the limbs during attacks and measured post-ictal regional cerebral blood flow (rCBF) in 3 patients with paroxysmal kinesigenic choreoathetosis (PKC). During attacks, a "Jacksonian march" pattern of tonic muscle activity in the limbs was observed. Two of 3 patients, who suffered from unilateral attacks, showed a noticeable increase in rCBF in the basal ganglia on the contralateral side of the attacks. Treatment with phenytoin improved symptoms and reduced the difference in rCBF between the right and left side. These observations suggest that abnormal hyperactivity of neurons in the basal ganglia may cause choreoathetotic movements in patients with PKC.

The level of tumor necrosis factor-alpha producing cells in the spinal cord correlates with the degree of Theiler's murine encephalomyelitis virus-induced demyelinating disease

The levels of tumor necrosis factor (TNF)-alpha producing cells were analyzed in mice with Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD). Using an ELISPOT assay, we demonstrate an increase in TNF-alpha producing cells in the spinal cords of TMEV-infected SJL/J mice, especially at an active disease stage. The numbers of TNF-alpha producing cells were extremely high in susceptible SJL/J mice compared with the numbers in resistant BALB/c and C57BL/6 mice. TNF-alpha producing cells were also immunohistochemically identified in active lesions of TMEV-IDD at acute as well as chronic stages. The percentage of TNF-alpha producing cells compared with the total number of cells isolated from spinal cords was higher in TMEV-infected SJL/J mice than resistant BALB/c and C57BL/6 mice. Correspondingly, the level of TNF-alpha was much higher in the culture supernatants of both infiltrating cells in the spinal cords and spleen cells from clinically affected animals than that from similarly treated resistant mice. Treatment of virus-infected mice with a mAb specific for TNF-alpha at the beginning of the onset of disease suppressed the development of the demyelinating disease. These findings suggest that TNF-alpha may play an important role in the pathogenicity of TMEV-IDD.

[A study on the pathogenesis of hepatomegaly in patients with Crow-Fukase syndrome]

We studied pathogenesis of hepatomegaly in Crow-Fukase syndrome. Hepatocytes were isolated from BALB/c mice and cultured with serum or ascites of three patients with Crow-Fukase syndrome. After 24 hours culture, total number of hepatocytes was counted. The levels of human hepatocyte growth factor (h-HGF) in the serum were also measured. In the hepatocyte culture study, the numbers of hepatocytes after 24 hours cultured in the serum of two patients were significantly larger than those of the control group. When the hepatocytes were cultured with patients' serum after corticosteroid therapy, the survival numbers were markedly reduced. The serum levels of h-HGF in our three patients were 0.62, 0.52, 0.53 ng/ml respectively. They were all slightly higher than normal values (< or = 0.39 ng/ml). Our study indicates that in the serum or ascites of patients with Crow-Fukase syndrome, there may be some humoral factors other than h-HGF, which promote proliferation of hepatocyte or protect hepatocyte.

[The detection of factors that may promote the hepatocyte proliferation in the serum of a patient with crow-fukase syndrome]

We reported a case of Crow-Fukase syndrome and examined the mechanism of hepatomegaly in Crow-Fukase syndrome. A 67-year-old woman was presented with polyneruopathy, hepatosplenomegaly, pericardial effusion and M proteinemia. On examination, all laboratory data and clinical symptoms were compatible with Crow-Fukase syndrome. The patient was treated with prednisolone and immunoadsorption plasmaphresis therapy. All the clinical manifestations including hepatomegaly gradually improved. In order to examine whether some factors that promote the prolifelation of hepatocyte may exist in the patient's serum, we cultured mouse hepatocyte in the presence of patient's or control serum together. Though the number of hepatocytes decreased after 2 days culture, the number of hepatocytes cultured with patient's serum in active disease stage remained significantly greater than of hepatocytes cultured with either control serum or patient's serum in healing stage. There were no abnormal pathological findings in biopsied liver. Liver suggesting that hepatomegaly was the results of normal hepatocytes proliferation. Taken together, these findings suggest there were some factors that may promote the proliferation of hepatocytes or may have protective effect of hepatocyte in patient's serum. Though the level of human hepatocyte growth factor (h-HGF) in patient's serum in active disease stage was slightly increased, hepatomegaly cannot be attributable solely to h-HGF. Organomegaly is one of the important symptoms of the Crow-Fukase syndrome, however, in so far as we are aware its mechanism is not examined. In this report it is suggested that several unknown factors other than h-HGF may contribute the hepatomegaly of the Crow-Fukase syndrome.

[A patient with a relapse of myasthenia gravis after a 13-year remission following successful treatment by mediastinal irradiation and corticosteroid therapy]

We report a patient with myasthenia gravis who experienced a relapse 13 years after apparently successful treatment by mediastinal irradiation and corticosteroid therapy. A 20-year-old male was admitted to Shinshu University Hospital with a chief complain double vision and drooping eyelids. These symptoms had appeared 2 months prior to admission. They tended to be more severe late in the day, and varied from day to day. Prior to this admission the patient had been healthy for the 13 years since undergoing 45-Gy mediastinal irradiation and corticosteroid therapy. MRI and CT studies revealed no thymic hyperplasia. Total thymectomy was performed, and his myasthenic symptoms, including the opthalmoplegia, improved. Histological examination of the resected thymus revealed an active thymus with germinal centers. Immunohistological studies showed an abundance of intracellular adhesion molecule-1 (ICAM-1) in the germinal centers and thymic medullary epithelium, and the presence of lymphoid function-associated antigen-1 (LFA-1) in thymic lymphocytes. ICAM-1 and LFA-1 are ligand of adhesion molecules which interact with each other and play an important role in antigen presentation. Acetylcholine receptor (ACh-R) antigen is known to be present in the thymus. The presence of both ICAM-1 and LFA-1 in the active thymus in this patient suggests that these adhesion molecules may have a role in ACh-R antigen presentation, causing myasthenia. These findings suggest that patients with myasthenia gravis who do not undergo total thymectomy have a risk of recurrence, even after long-term remission.

[Characterization of infiltrating mononuclear cells in the spinal cords of Lewis rats with experimental autoimmune encephalomyelitis (EAE)]

Mononuclear cells (MNCs) infiltrating in spinal cords (SCs) of Lewis rats with EAE were isolated in order to permit flow cytometric (FCM) analysis of these cell populations, using monoclonal antibody to T cell, CD4, CD8. MHC class II antigen (Ia), intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function associated antigen-1 (LFA-1). The number of MNCs isolated from SC varied from 5 to 620 x 10(4). They were increased and reached a peak on day 2 post clinical onset, and subsequently declined through the clinical course. The increase of infiltrating cells in SC paralleled the severity of the disease development. The surface phenotypes of MNCs from rats on the day of clinical onset were determined by flow cytometry. The phenotypes found in these rats were as follows: T cells (70.3%); CD4 + (58.3%); CD8 + (40.3%); Ia (51.9%); ICAM-1 (62.6%); LFA-1 (75.8%). These findings suggest that high proportion of ICMA-1 and LFA-1 expression may be important in antigen presentation in the inflammatory lesions of SC and in promoting lymphocyte extravasation across the blood-brain barrier during the disease. The approach we employed offered more sophisticated and quantitative analysis of CNS inflammatory cells, which is unobtainable by tissue section staining.

Hemiballism with striatal hyperintensity on T1-weighted MRI in diabetic patients: a unique syndrome

We report 3 diabetic patients who developed hemiballism without involvement of the subthalamic nucleus. Each patient exhibited vigorous, flinging, ballistic involuntary movements in the extremities and slight facial grimacing involving one side of the body. Although diabetes was poorly controlled in all 3, each patient was nonketotic at the onset of hemiballism. Magnetic resonance imaging (MRI), in these patients showed abnormalities in the striatum contralateral to the hemiballism that were characterized by an increase in intensity on T1-weighted images and a slight decrease in intensity on T2-weighted images, and these changes persisted for more than 2 months. The striatal lesions are presumed to have developed following mild ischemia in the territory of the lateral striate branches of the middle cerebral artery. This combination of hemiballism and striatal lesions in diabetic patients may constitute a unique syndrome.

[A pathogenic study of chronic inflammatory demyelinating polyradiculoneuropathy in a patient with hepatitis B infection]

We immunologically examined the pathogenesis of chronic inflammatory demyelinating polyradiculoneuropathy in a patient with HB hepatitis. A 41-year-old male clerk has been suffered from muscle weakness, tingling and numbness in the distal portion of all limbs. All symptoms were compatible with the typical patterns of chronic inflammatory demyelinating polyradiculoneuropathy. We examined the patient's serum and biopsied sural nerve, using histochemical and immunological techniques. We detected the band that reacted with anti-HBs antibody in the sural nerve in western blotting. The result indicated that HBs antigen was expressed on the peripheral nerves in the patient. There were no anti-peripheral nerve antibodies neither in the sural nerve or serum. There was no increase of immune complex in the serum. No deposition of immunoglobulins and complements were detected in the sural nerve. Immunoadsorption therapy had no effect on this patient, but administration of prednisolone improved his symptoms drastically. These findings suggest that a cytotoxic T cell may had played a more important role than humoral factors in this patient's nerve injury. Though the pathogenesis of chronic inflammatory demyelinating polyradiculoneuropathy remains unclear, our findings seem to be very interesting in that they go some way toward clarifying the pathogenesis of this disease.

Fatal and near fatal asthma

Despite the recent development of apparently effective asthma drugs, the number of deaths from asthma has not declined. The authors tried to establish an optimal strategy for the prevention of acute asthmatic death by analyzing the circumstances of acute fatal or near-fatal asthma. Data were collected from 51 adult patients admitted to Bokutoh Tertiary Emergency Center due to acute asthma between November 1985 and May 1990 and 38 asthmatic patients admitted to Yokohama City Hospital in 1990. Pre-admission data were obtained through interviews with the patients, their families, or doctors who had seen them. A total of 89 patients were classified into three subgroups: group 1 consisted of patients dead-on-arrival (DOA); group 2, non-DOA patients with disturbed consciousness; and group 3, patients with less severe episodes. Little background information was significantly different among groups, but symptomatic episodes in group 1 patients tended to occur more rapidly. The speed of onset of the episodes was also dependent on the asthma control status. Prehospital care of groups 1 and 2 patients was very poor despite severity of the symptoms. All patients in groups 2 and 3 were successfully treated and discharged, but five of the 26 patients in group 2 died during follow-up periods. Prognosis of patients after discharge appeared to be dependent upon asthma control status before the acute episodes. It was concluded that acute fatal or near fatal asthma could occur in apparently low-risk patients as well as high-risk ones. It was also suggested that the optimal strategy for preventing asthma deaths might be variable.