Intronic variant in IQGAP3 associated with hereditary neuropathy with proximal lower dominancy, urinary disturbance, and paroxysmal dry cough.

In 2008, we reported a clinically and genetically new type of autosomal dominant disorder of motor and sensory neuropathy with proximal dominancy in the lower extremities, urinary disturbance, and paroxysmal dry cough. To identify the nucleotide variant causative of this disease, we reanalyzed the linkage of the original Japanese pedigree including seven newly ascertained subjects with updated information. We assigned the locus of the disease to 1p13.3-q23 (maximum logarithm-of-odds score = 2.71). Exome sequencing for five patients and one healthy relative from the pedigree revealed 2526 patient-specific single-nucleotide variants (SNVs). By rigorous filtering processes using public databases, our linkage results, and functional prediction, followed by Sanger sequencing of the pedigree and 520 healthy Japanese individuals, we identified an intronic SNV in IQGAP3, a gene known to be associated with neurite outgrowth. Upon pathological examination of the sural nerve, moderate, chronic, mainly axonal neuropathy was observed. By histochemical analyses, we observed a patient-specific increase of IQGAP3 expression in the sural nerve. We concluded that the variant of IQGAP3 is associated with the disease in our pedigree.

Increased expression of OX40 is associated with progressive disease in patients with HTLV-1-associated myelopathy/tropical spastic paraparesis.

BACKGROUND: OX40 is a member of the tumor necrosis factor receptor family that is expressed primarily on activated CD4+ T cells and promotes the development of effector and memory T cells. Although OX40 has been reported to be a target gene of human T-cell leukemia virus type-1 (HTLV-1) viral transactivator Tax and is overexpressed in vivo in adult T-cell leukemia (ATL) cells, an association between OX40 and HTLV-1-associated inflammatory disorders, such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), has not yet been established. Moreover, because abrogation of OX40 signals ameliorates chronic inflammation in animal models of autoimmune disease, novel monoclonal antibodies against OX40 may offer a potential treatment for HTLV-1-associated diseases such as ATL and HAM/TSP. RESULTS: In this study, we showed that OX40 was specifically expressed in CD4+ T cells naturally infected with HTLV-1 that have the potential to produce pro-inflammatory cytokines along with Tax expression. We also showed that OX40 was overexpressed in spinal cord infiltrating mononuclear cells in a clinically progressive HAM/TSP patient with a short duration of illness. The levels of the soluble form of OX40 (sOX40) in the cerebrospinal fluid (CSF) from chronic progressive HAM/TSP patients or from patients with other inflammatory neurological diseases (OINDs) were not different. In contrast, sOX40 levels in the CSF of rapidly progressing HAM/TSP patients were higher than those in the CSF from patients with OINDs, and these patients showed higher sOX40 levels in the CSF than in the plasma. When our newly produced monoclonal antibody against OX40 was added to peripheral blood mononuclear cells in culture, HTLV-1-infected T cells were specifically removed by a mechanism that depends on antibody-dependent cellular cytotoxicity. CONCLUSIONS: Our study identified OX40 as a key molecule and biomarker for rapid progression of HAM/TSP. Furthermore, blocking OX40 may have potential in therapeutic intervention for HAM/TSP.

Chronic severe axonal polyneuropathy associated with hyperthyroidism and multivitamin deficiency.

OBJECTIVES: Hyperthyroidism is often associated with various neuromuscular disorders, most commonly proximal myopathy. Peripheral nerve involvement in hyperthyroidism is very uncommon and has rarely been reported. We describe a 29-year-old woman with untreated hyperthyroidism who presented with chronic severe axonal sensory-motor polyneuropathy. Peripheral nerve involvement developed together with other symptoms of hyperthyroidism 2 years before presentation. She also had anorexia nervosa for the past 6 months, resulting in multivitamin deficiency. RESULTS: Electrophysiological and pathological findings as well as clinical manifestations confirmed the diagnosis of severe axonal polyneuropathy. Anorexia nervosa has been considered a manifestation of untreated hyperthyroidism. We considered hyperthyroidism to be an important causal factor in the polyneuropathy in our patient, although peripheral nerve involvement in hyperthyroidism is rare. To our knowledge, this is the first documented case of chronic severe axonal polyneuropathy ascribed to both hyperthyroidism and multivitamin deficiency. CONCLUSION: Our findings strongly suggest that not only multivitamin deficiency, but also hyperthyroidism can cause axonal polyneuropathy, thus expanding the clinical spectrum of hyperthyroidism.

Spinocerebellar ataxia with axonal neuropathy: consequence of a Tdp1 recessive neomorphic mutation?

Tyrosyl-DNA phosphodiesterase 1 (Tdp1) cleaves the phosphodiester bond between a covalently stalled topoisomerase I (Topo I) and the 3' end of DNA. Stalling of Topo I at DNA strand breaks is induced by endogenous DNA damage and the Topo I-specific anticancer drug camptothecin (CPT). The H493R mutation of Tdp1 causes the neurodegenerative disorder spinocerebellar ataxia with axonal neuropathy (SCAN1). Contrary to the hypothesis that SCAN1 arises from catalytically inactive Tdp1, Tdp1-/- mice are indistinguishable from wild-type mice, physically, histologically, behaviorally, and electrophysiologically. However, compared to wild-type mice, Tdp1-/- mice are hypersensitive to CPT and bleomycin but not to etoposide. Consistent with earlier in vitro studies, we show that the H493R Tdp1 mutant protein retains residual activity and becomes covalently trapped on the DNA after CPT treatment of SCAN1 cells. This result provides a direct demonstration that Tdp1 repairs Topo I covalent lesions in vivo and suggests that SCAN1 arises from the recessive neomorphic mutation H493R. This is a novel mechanism for disease since neomorphic mutations are generally dominant.

Adult-type metachromatic leukodystrophy with compound heterozygous ARSA mutations: a case report and phenotypic comparison with a previously reported case.

Metachromatic leukodystrophy (MLD) is an autosomal recessive lysosomal storage disease caused by a deficiency of arylsulfatase A. MLD is a heterogeneous disease with variable age at onset and variable clinical features. We evaluated a 33-year-old female patient who developed manifestations of disinhibitory behavior. She was diagnosed with MLD by genetic analysis, which revealed compound heterozygous ARSA missense mutations (p.G99D and p.T409I). The same combination of mutations was previously reported in a Japanese patient with similar symptoms. We performed additional, detailed neuropsychological tests with functional imaging on the current patient that demonstrated frontal lobe dysfunction. These results indicate that the mutations have important implications for genotype-phenotype correlation in MLD.

Surgical Treatment for Mesial Temporal Lobe Epilepsy Accompanied with Neuro-Behçet's Disease: A Case Report.

Behçet's disease (BD) is a rare chronic inflammatory disease associated with systemic vasculitis. Involvement of the nervous system in BD is called neuro-BD (NBD). Epilepsy related to NBD is uncommon but responds well to anti-epileptic drugs. We present a case of NBD with drug-resistant mesial temporal lobe epilepsy (MTLE) due to hippocampal sclerosis (HS). The patient presented with headache, dizziness, disorientation, and generalized seizures. Magnetic resonance imaging (MRI) identified pontine lesions. Chronic inflammation was suspected, and steroid pulse therapy improved his symptoms. He relapsed 1 year after onset and was diagnosed with NBD. MRI revealed bilateral mesial temporal lesions, with the right being edematous and the left atrophic. NBD was controlled by steroid and immunosuppressive medication. Three years after the onset of NBD, the patient suffered MTLE, and MRI suggested left hippocampal atrophy. His seizures became drug-resistant and surgical therapy was considered 12 years after NBD onset. Pre-surgical MRI clearly showed left HS. After evaluations, the patient had left anterior temporal lobectomy (ATL) 13 years after NBD onset under stable NBD. The patient was seizure-free for > 2 years after surgery. Surgery will be an effective treatment for drug-resistant MTLE with HS even in patients with NBD, of course the effects of surgical intervention should be considered.

[Autopsy case of dural thickening caused by widespread dural vein thrombosis associated with disseminated bone marrow carcinomatosis].

A 64-year-old woman was referred to our hospital because of disturbance of consciousness. She had undergone distal gastrectomy for gastric carcinoma 17 years previously. General physical examination was unremarkable, neurologic examination disclosed hyperactive deep tendon reflexes in the upper limbs. Laboratory abnormalities included elevations of alkaline phosphatase (ALP) and lactate dehydrogenase (LDH), and findings suggesting disseminated intravascular coagulation (DIC). Lumbar cerebrospinal fluid showed a protein concentration of 408 mg/dl and a glucose concentration of 82 mg/dl (blood: 110 mg/dl), as well as a cell count of 16/mm3. Cranial computed tomography indicated brain edema. Magnetic resonance imaging (MRI) of the brain showed diffuse thickening of the dura mater, with contrast enhancement upon gadolinium-DTPA administration. These findings suggested hypertrophic pachymeningitis. Magnetic resonance venography (MRV) showed occlusion of the left transverse sinus and attenuation of the straight sinus. MRI of the spine as well as gallium scintigrams demonstrated multiple areas of increased uptake in areas near the skull and spine. We therefore suspected tumor metastasis. The patient was given heparin as well as pulse therapy with methylprednisolone, but she died 7 weeks after symptom onset. At postmortem examination, the dura was thickened. Histopathologically, numerous tumor cell emboli in the dura were confined to the lumens of veins. The tumor cells were thought to have metastasized to the dura through the vertebral venous plexus (Batson's plexus). Immunostaining demonstrated immunoreactivity of tumor cells to epithelial membrane antigen (EMA) and carcinoembryonic antigen (CEA). The primary origin of the carcinoma was not precisely identified by these findings. Widespread dural vein tumor emboli should be taken into consideration as a cause in cases that develop rapid deterioration of consciousness associated dura mater thickening.

Inclusion body myositis associated with human T-lymphotropic virus-type I infection: eleven patients from an endemic area in Japan.

The objective of this study was to investigate the association of human T-lymphotropic virus-type I (HTLV-I) infection with sporadic inclusion body myositis in 11 patients from an endemic area in Japan. The clinical features were consistent with sporadic inclusion body myositis, and anti-HTLV-I antibodies were present in the sera of all patients. Their muscle biopsies showed the diagnostic features of inclusion body myositis, including endomysial T-cell infiltration, rimmed vacuoles, deposits of phosphorylated tau, and abnormal filaments in the nuclei and cytoplasm of the myofibers. The fibers expressed major histocompatibility complex class I antigens and were invaded by CD8 and CD4 cells. In a single human leukocyte antigen-A2-positive patient, in situ human leukocyte antigen-A*0201 / Tax11-19-pentamer staining showed pentamer-positive cells surrounding the muscle fibers. Double-immunogold silver staining and polymerase chain reaction in situ hybridization revealed that HTLV-I proviral DNA was localized on helper-inducer T cells, but not on muscle fibers. Human T-lymphotropic virus-type I proviral loads in peripheral blood mononuclear cells from each patient were similar to those in HTLV-I-associated myelopathy/tropical spastic paraparesis. This study suggests that HTLV-I infection may be one of the causes of sporadic inclusion body myositis, as has been reported in human immunodeficiency virus type-1 infection.

Accumulation of human T-lymphotropic virus type I (HTLV-I)-infected cells in the cerebrospinal fluid during the exacerbation of HTLV-I-associated myelopathy.

Human T-lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a slowly progressive, inflammatory disease of the central nervous system (CNS). We report a patient with transverse myelitis, who exhibited acute onset and rapid progression of the disease and whose symptoms resembled those observed in multiple sclerosis with spinal cord presentation. During neurological exacerbation of the condition, the HTLV-I proviral load in the cerebrospinal fluid (CSF) increased to 10 times that in the peripheral blood. This suggests that the accumulation of HTLV-I-infected cells in the CNS contributes to neurological exacerbation. Based on the increased proviral load in the CSF, we diagnosed the disease as acute progressive HAM/TSP. The measurement of the HTLV-I proviral load in the CSF is useful for the diagnosis of HAM/TSP and for monitoring its progression.

Enlarged, multifocal upper limb neuropathy with HTLV-I associated myelopathy in a patient with chronic adult T-cell leukemia.

The authors herein describe a case of multifocal peripheral neuropathy with HTLV-I-associated myelopathy (HAM) in a patient with chronic adult T-cell leukemia (ATL). The clinical features included subacute progressive sensory-motor neuropathy in the bilateral upper limbs, and bilateral pyramidal tract involvement with bladder dysfunction. An MRI with (67)gadolinium enhancement revealed enlargement of the affected peripheral nerves. (8)FDG positron emission tomography (PET) disclosed increased uptake in the affected nerves, suggesting neurolymphomatosis or inflammation. Anti-HTLV-I antibody was positive in both the serum and CSF. The HTLV-I proviral load in the peripheral blood mononuclear cells was high. Chemotherapy for ATL resulted in marked improvement of motor functions in the upper limbs. This is the first case of multifocal upper limb neuropathy with HAM in a patient with chronic ATL.

Motor-sensory neuropathy without minifascicles in a patient with 46XY gonadal dysgenesis.

We report a 36-year-old patient with 46XY pure gonadal dysgenesis (GD), who manifested a syndrome of progressive motor-sensory neuropathy. Sural nerve biopsy showed severe axonal neuropathy. Since reported cases of chronic motor-sensory neuropathy and pure gonadal dysgenesis have been characterized by nerve biopsy evidence of minifascicle formation, we suggest that this clinical association may be a new type of hereditary motor-sensory neuropathy, not necessarily associated with minifascicle formation.

[A case of mitochondrial disease with multiple mitochondrial DNA deletions suspected amyotrophic lateral sclerosis-frontotemporal dementia].

A 76-year-old woman showed a dramatic lowering of her tone of voice in October 2014, followed by muscle weakness of the left arm. The previous attending physician noticed remarkable left dominant frontotemporal lobe atrophy on cranial MRI. Her dysarthria, dysphagia and the muscle weakness of her extremities worsened, and a muscle biopsy revealed mitochondrial abnormality. The mitochondrial DNA from her muscle showed multiple deletions; the previous physician therefore diagnosed the patient with mitochondrial disease. The patient resembled amyotrophic lateral sclerosis-frontotemporal dementia (ALS-FTD). No other cases of ALS-FTD with mitochondrial disease have been reported in Japan. We therefore consider the present case to be valuable.

The structural and functional integrity of peripheral nerves depends on the glial-derived signal desert hedgehog.

We show that desert hedgehog (dhh), a signaling molecule expressed by Schwann cells, is essential for the structural and functional integrity of the peripheral nerve. Dhh-null nerves display multiple abnormalities that affect myelinating and nonmyelinating Schwann cells, axons, and vasculature and immune cells. Myelinated fibers of these mice have a significantly increased (more than two times) number of Schmidt-Lanterman incisures (SLIs), and connexin 29, a molecular component of SLIs, is strongly upregulated. Crossing Dhh-null mice with myelin basic protein (MBP)-deficient shiverer mice, which also have increased SLI numbers, results in further increased SLIs, suggesting that Dhh and MBP control SLIs by different mechanisms. Unmyelinated fibers are also affected, containing many fewer axons per Schwann cell in transverse profiles, whereas the total number of unmyelinated axons is reduced by approximately one-third. In Dhh-null mice, the blood-nerve barrier is permeable and neutrophils and macrophage numbers are elevated, even in uninjured nerves. Dhh-null nerves also lack the largest-diameter myelinated fibers, have elevated numbers of degenerating myelinated axons, and contain regenerating fibers. Transected dhh nerves degenerate faster than wild-type controls. This demonstrates that a single identified glial signal, Dhh, plays a critical role in controlling the integrity of peripheral nervous tissue, in line with its critical role in nerve sheath development (Parmantier et al., 1999). The complexity of the defects raises a number of important questions about the Dhh-dependent cell-cell signaling network in peripheral nerves.

[Portal-systemic encephalopathy with bilateral thalamic and internal capsule lesions using diffusion-weighted MRI in a super-aged patient].

We describe the case of a 90-year-old woman who was hospitalized in July 2016 and subsequently experienced a sudden decline in consciousness level resulting in a state of deep coma. Involuntary movements were not observed, and bilateral Babinski signs were inconclusive. Diffusion-weighted MRI (DWI) of the brain showed bilateral hyperintensity in the thalamus and internal capsule, laboratory testing detected high levels of plasma ammonia, and an electroencephalogram showed delta waves and triphasic waves predominantly in the frontal lobe. Based on these results, treatment for hepatic encephalopathy was administered, which led to an improvement in consciousness level, a decrease in plasma ammonia levels, and a normalization in the DWI scan. Abdominal computed tomography scan showed no abnormality in the liver, but revealed an abnormal blood vessel leading from the ileocolic vein to the inferior vena cava; the patient was diagnosed with portal-systemic encephalopathy. In deep coma patients, acute encephalopathy with hyperammonemia is important for differential diagnosis when DWI shows high-density legions in the thalamus and internal capsule.

Elevated anxiety-like and depressive behavior in Desert hedgehog knockout male mice.

To investigate the functional role of Desert hedgehog (Dhh) gene in the nervous system, we examined motor, sensory, learning and memory functions as well as mood in Dhh knockout (KO) mice. Dhh KO male mice exhibited prolonged immobility time compared with wild-type male mice in the forced swimming test, and showed enhanced inhibition in the Vogel's conflict model. These findings suggest that Dhh KO male mice exhibited enhanced anxiety and depressive behavior compared with wild-type male mice. In contrast, Dhh KO female mice did not show any significant difference compared to wild-type female mice. These behavioral abnormalities of Dhh KO male mice may be due to lower testosterone levels with abnormal development of the testes caused by Dhh-null mutation.

Chronic progressive sensory ataxic neuropathy associated with limited systemic sclerosis.

We report the case of a 33-year-old woman with limited systemic sclerosis and chronic progressive sensory ataxic neuropathy. Sural nerve biopsy showed loss of myelinated fibers mostly those of large diameter, axonal degeneration and infiltration of macrophages, but no signs of vasculitis. Physical examination, laboratory testing, neurophysiological and neuroradiological examinations suggested that the dorsal root was primarily affected in this patient. Cytokine analysis by multiplex bead array assay revealed that IL-1beta and GM-CSF were increased both in serum and CSF. Although her symptoms did not respond to corticosteroid therapy, intravenous immunoglobulin (IVIg) therapy resulted in marked improvement. IVIg could be effective in case of immune-mediated reversible neuronal dysfunction associated with collagen disease without vasculitis.

MRI studies of spinal visceral larva migrans syndrome.

We report serial MR findings in four patients with myelitis caused by visceral larva migrans syndrome due to Toxocara canis or Ascaris suum infection. MR imaging revealed spinal cord swelling with or without gadolinium enhancement in three patients. T2-weighted images showed high signal intensities preferentially located in both lateral and posterior columns. Antihelmintic and corticosteroid treatment yielded improvement in neurologic deficits and spinal lesions. However, one patient with T. canis infection relapsed associated with reappearance of MRI abnormalities.

[A case of bilateral blephaloptosis resulting from midbrain lesions caused by diffuse large B-cell lymphoma].

We report the case of a patient with bilateral blephaloptosis associated with a recurrence of diffuse large B-cell lymphoma (DLBCL) in the midbrain. A 70-year-old man experienced acute onset bilateral blephaloptosis; the other ocular movements, except for medial rectus muscle in the right eye, were not impaired. Pupils were isocoric and light reflexes were prompt. Other cranial nerves were intact. Gadolinium-enhanced MRI revealed abnormal enhancement in the midbrain and peri-ventricular regions. FDG-PET revealed an abnormal positive signal in the midbrain, similar to the distribution seen in the MRI scan. Cytology of the cerebrospinal fluid showed large atypical lymphocytes. These findings suggest that the recurrence of DLBCL in the midbrain caused bilateral blephaloptosis. The oculomotor fascicle is localized in the paramedian ventral midbrain. The fascicular fibers are divided topographically into four regions; the lateral, medial, rostral and caudal regions. In three-dimensional arrangement of the oculomotor fascicle, the fibers to the levator palpebrae superioris muscle and medial rectus muscles are located adjacently in caudal regions. Thus, we speculate that recurrence of DLBCL in the midbrain involving the right oculomotor fascicle caused blephaloptosis in the right eye, and then, infiltration of DLBCL to the left oculomotor fascicle subsequently caused blephaloptosis in the left eye. This is a valuable case to be documented in which neurological site of lesions consistent with those are found in radiological study.

[Chronic progressive cervical myelopathy with HTLV-I infection: variant form of HAM/TSP].

We report four patients with slowly progressive cervical myelopathy. The four patients had several features in common; 1) progressive cervical myelopathy with a duration of several months to years, 2) abnormal lesions in the cervical to upper thoracic cord levels with or without gadolinium enhancement, 3) anti-HTLV-I antibodies were positive both in serum and CSF, 4) high levels of HTLV-I proviral load in PBMC. The calculated risk of HAM/TSP in two patients showed a high value, comparable to those of HAM/TSP, and higher than those of healthy HTLV-I carrier. Because the clinical and laboratory findings of these four cases show similarities to those of HAM/TSP, we propose that these four cases may be a variant form of HAM/TSP.

Selective matrix metalloproteinase inhibitor, N-biphenyl sulfonyl phenylalanine hydroxamic acid, inhibits the migration of CD4+ T lymphocytes in patients with HTLV-I-associated myelopathy.

Matrix metalloproteinases (MMPs) have been reported to be involved in various inflammatory disorders. Previous studies revealed that MMP-2 and MMP-9 might play important roles in the breakdown of the blood-brain barrier (BBB) in the central nervous system (CNS) of patients with HTLV-I-associated myelopathy (HAM)/tropical spastic paraparesis (TSP). N-Biphenyl sulfonyl-phenylalanine hydroxamic acid (BPHA) selectively inhibits MMP-2, -9 and -14, but not MMP-1, -3 and -7. In the present study, we examined whether or not the selective MMP inhibitor BPHA could inhibit the heightened migrating activity of CD4+ T cells in HAM/TSP patients. The migration assay using an invasion chamber showed that migration of CD4+ T cells in HAM/TSP patients was inhibited by 25 microM BPHA. In addition, the inhibitory ratio of migrating CD4+ lymphocytes was higher in HAM patients compared to normal controls. These results suggest that the selective MMP inhibitor BPHA has therapeutic potential for HAM/TSP.