Comprehensive Research on Past and Future Therapeutic Strategies Devoted to Treatment of Amyotrophic Lateral Sclerosis.

Amyotrophic lateral sclerosis (ALS) is a rapidly debilitating fatal neurodegenerative disorder, causing muscle atrophy and weakness, which leads to paralysis and eventual death. ALS has a multifaceted nature affected by many pathological mechanisms, including oxidative stress (also via protein aggregation), mitochondrial dysfunction, glutamate-induced excitotoxicity, apoptosis, neuroinflammation, axonal degeneration, skeletal muscle deterioration and viruses. This complexity is a major obstacle in defeating ALS. At present, riluzole and edaravone are the only drugs that have passed clinical trials for the treatment of ALS, notwithstanding that they showed modest benefits in a limited population of ALS. A dextromethorphan hydrobromide and quinidine sulfate combination was also approved to treat pseudobulbar affect (PBA) in the course of ALS. Globally, there is a struggle to prevent or alleviate the symptoms of this neurodegenerative disease, including implementation of antisense oligonucleotides (ASOs), induced pluripotent stem cells (iPSCs), CRISPR-9/Cas technique, non-invasive brain stimulation (NIBS) or ALS-on-a-chip technology. Additionally, researchers have synthesized and screened new compounds to be effective in ALS beyond the drug repurposing strategy. Despite all these efforts, ALS treatment is largely limited to palliative care, and there is a strong need for new therapeutics to be developed. This review focuses on and discusses which therapeutic strategies have been followed so far and what can be done in the future for the treatment of ALS.

Altered Functional Connectivity during Mild Transient Respiratory Impairment Induced by a Resistive Load.

Background: Previous neuroimaging studies have identified brain regions related to respiratory motor control and perception. However, little is known about the resting-state functional connectivity (FC) associated with respiratory impairment. We aimed to determine the FC involved in mild respiratory impairment without altering transcutaneous oxygen saturation. Methods: We obtained resting-state functional magnetic resonance imaging data from 36 healthy volunteers during normal respiration and mild respiratory impairment induced by resistive load (effort breathing). ROI-to-ROI and seed-to-voxel analyses were performed using Statistical Parametric Mapping 12 and the CONN toolbox. Results: Compared to normal respiration, effort breathing activated FCs within and between the sensory perceptual area (postcentral gyrus, anterior insular cortex (AInsula), and anterior cingulate cortex) and visual cortex (the visual occipital, occipital pole (OP), and occipital fusiform gyrus). Graph theoretical analysis showed strong centrality in the visual cortex. A significant positive correlation was observed between the dyspnoea score (modified Borg scale) and FC between the left AInsula and right OP. Conclusions: These results suggested that the FCs within the respiratory sensory area via the network hub may be neural mechanisms underlying effort breathing and modified Borg scale scores. These findings may provide new insights into the visual networks that contribute to mild respiratory impairments.

A Case in which Eosinophilic Meningoencephalitis Occurred during Oral Corticosteroid Tapering and after Switching from Anti-IL-5 to Anti-IgE Treatment.

A 49-year-old man with severe eosinophilic asthma, sinusitis, and esophagitis was admitted with a sudden severe headache. The patient was diagnosed with eosinophilic meningoencephalitis based on frontotemporal abnormalities on brain magnetic resonance imaging and high eosinophil counts in the cerebrospinal fluid. His allergic-disease control levels were poor, requiring regular oral corticosteroid (OCS) use. He was switched from anti-interleukin (IL)-5 to anti-IgE therapy because of worsening urticaria and asthma symptoms during OCS tapering. We suspect this was a case of complex eosinophilic meningoencephalitis caused by the combination of OCS tapering and anti-IL-5 therapy cessation that acquired anti-IgE antibody sensitization based on positive drug-induced lymphocyte stimulation test results.

A case of hereditary diffuse leukoencephalopathy with axonal spheroids caused by a de novo mutation in CSF1R masquerading as primary progressive multiple sclerosis.

We report a sporadic case of hereditary diffuse leukoencephalopathy with axonal spheroids (HDLS) confirmed by biopsy and colony-stimulating factor 1 receptor (CSF1R) sequencing. A 28-year-old woman developed progressive spastic gait and dysarthria. Brain T2/FLAIR-weighted magnetic resonance imaging showed bilateral high signal intensity lesions in the parietal deep white matter, which subsequently extended anteriorly. Biopsied brain specimens demonstrated demyelinated white matter tissue with axonal spheroids infiltrated with foamy macrophages, and CD8(+) and CD4(+) T cells. She had a heterozygous mutation, c.2381T>C (p.782 Ile>Thr), in CSF1R. This is the first genetically proven case of HDLS mimicking primary progressive multiple sclerosis.

[A case of very long chain acyl-CoA dehydrogenase deficiency diagnosed due to a trigger of hyperemesis gravidarum during pregnancy].

A 25-year-old Japanese woman with a history of repeated episodes of rhabdomyolysis since the age of 12 presented with rhabdomyolysis caused by hyperemesis gravidarum. Blood tests showed an elevated serum CK level (11,755 |IU/l; normal: 30-180 |IU/l). Carnitine fractionation analysis revealed low levels of total carnitine (18.3 |µmol/l; normal: 45-91 |µmol/l), free carnitine (13.1 |µmol/l; normal: 36-74 |µmol/l), and acylcarnitine (5.2 |µmol/l; normal: 6-23 |µmol/l). Tandem mass spectrometry showed high levels of C14:1 acylcarnitine (0.84 |nmol/ml: normal: <0.4 |nmol/ml) and a high C14:1/C2 ratio of 0.253 (normal: <0.013), indicating a potential diagnosis of very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency. Enzyme activity measurement in the patient's peripheral blood lymphocytes confirmed the diagnosis of VLCAD deficiency, with low palmitoyl-CoA dehydrogenase levels (6.5% of normal control value). With the patient's informed consent, acyl-CoA dehydrogenase very long-chain (ACADVL) gene analysis revealed compound heterozygous mutations of c.1332G>A in exon 13 and c.1349G>A (p.R450H) in exon 14. In Japan, neonatal mass screening is performed to detect congenital metabolic diseases. With the introduction of tandem mass screening in 2014, fatty acid metabolism disorders, including VLCAD deficiency, are being detected before the onset of symptoms. However, it is important to note that mass screening cannot detect all cases of this disease. For patients with recurrent rhabdomyolysis, it is essential to consider congenital diseases, including fatty acid metabolism disorders, as a potential diagnosis.

Hereditary Neuralgic Amyotrophy with a Lesion Distal to the Brachial Plexus on Magnetic Resonance Imaging.

A 35-year-old woman first experienced left upper limb weakness at 17 years old, after which it repeatedly recurred and then remitted. She was diagnosed with carpal tunnel syndrome with median nerve hyperintensity by magnetic resonance imaging (MRI). Surgical treatment was ineffective. We suspected hereditary neuralgic amyotrophy because of enlargement distal to the brachial plexus on MRI and administered steroid therapy, after which the weakness improved. Genetic testing revealed a point mutation in SEPT9. Because lesions outside the brachial plexus can be seen in hereditary neuralgic amyotrophy, the diagnosis should be based on typical characteristics and the family history.

Association of Myelin Oligodendrocyte Glycoprotein Antibody-associated Disease with Coronavirus Disease 2019 Vaccination and Infection: A Case Report of Cortical Encephalitis and Transverse Myelitis Relapse.

We herein report a case of myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) that occurred following coronavirus disease 2019 (COVID-19) vaccination and its subsequent relapse after COVID-19 infection. A 34-year-old woman developed cortical encephalitis in the right temporoparietal lobe one week after receiving the mRNA-1273 vaccine. The cerebrospinal fluid was positive for anti-MOG antibody. Her symptoms gradually improved after three courses of intravenous methylprednisolone therapy. Six months later, she experienced a relapse of transverse myelitis following COVID-19 infection. Despite treatment with plasma exchange, the patient remained paralyzed in both lower limbs. We herein review the relationship between MOGAD and COVID-19 vaccination/infection.

[A case of localized fasciitis with ulcerative colitis].

A 36-year-old man with ulcerative colitis presented with bloody stools at the beginning of October 2020. His condition had been stable without treatment since diagnosis 4 years prior. He was administered 4,000 mg of salazosulfapyridine orally and the bloody stools resolved. Fifteen days after treatment, he was admitted to our hospital with swelling and pain in his right lower leg. Laboratory results revealed an elevated erythrocyte sedimentation rate (43 mm/hr) and mildly elevated C-reactive protein levels (4.08 mg/dl). His D-dimer level was also elevated at 7.6 µg/ml. MRI using fat saturated T2-weighted imaging demonstrated marked hyperintensity in the fascia of the lower leg flexor and blood vessels of interstitial. In gadolinium-enhanced T1-weighted images, the deep veins were found to be dilated and the vein walls and their surrounding areas strongly contrasted, suggestive of localized fasciitis. No abnormalities were found on biopsy of his right gastrocnemius muscle on the 5th day after admission. Two days after the muscle biopsy, the patient began experiencing swelling and pain in his left lower leg. The high intensity lesions in his right leg were reduced on MRI performed the same day, but that of the fascia between the left gastrocnemius and soleus muscles was noted. We administered 60 mg (1.0 mg/kg/day) of prednisolone orally on day 9 and the pain and swelling in both legs promptly resolved. The prednisolone was tapered to 5 mg/day and as of the time of writing, resolution of pain and swelling has been maintained. Gastrocnemius myalgia syndrome, which causes pain and localized fasciitis, is often reported as a complication of Crohn's disease but is rare in conjunction with ulcerative colitis. It is important that clinicians are aware of this syndrome so it can be recognized early and successfully treated.

Anti-glycine receptor antibody-positive progressive encephalomyelitis with rigidity and myoclonus initially presenting with one-sided stiff face: A case report.

Background: Progressive encephalomyelitis with rigidity and myoclonus (PERM) is a subtype of stiff-person syndrome, a rare cerebrospinal disease that causes brainstem symptoms, myoclonus, muscle rigidity, and hyperekplexia. Case presentation: A 71-year-old man experienced left-sided stiff face, and was subsequently admitted to our hospital because of the appearance of left-dominant lower limb myoclonus. Muscle rigidity followed 3 days later. Magnetic resonance imaging revealed no abnormality. An electrophysiological examination showed a toughness of the antagonistic muscle following evocation of the Achilles tendon reflex, and a tonic phenomenon affecting the left facial muscles during the blink reflex. The patient's serum was positive for anti-glycine receptor (anti-GlyR) antibody, suggesting PERM. The patient was administered steroids, immunoglobulin therapy, and immunosuppressive drugs. He gradually improved after these therapies and became able to walk using a walker. Conclusions: We conclude that this was a rare case of anti-GlyR antibody-positive PERM with unilateral brainstem symptoms, myoclonus, and muscle rigidity.

[Chronic progressive external ophthalmoplegia that could not be diagnosed by biceps muscle biopsy, but was genetically diagnosed by extraocular muscle biopsy].

A 48-year-old Japanese male experienced slowly progressive diplopia. He had no family history and was negative for the edrophonium chloride test. Blood analysis showed elevated lactic acid and pyruvic acid levels, suggesting mitochondrial disease. A muscle biopsy from the biceps brachii was performed, but no pathological or genetical mitochondrial abnormalities were detected. Subsequently, he underwent muscle plication for diplopia in which the right inferior rectus muscle was biopsied. Genetic examination of genomic DNA extracted from the extraocular muscle tissue revealed multiple mitochondrial gene deletions, with a heteroplasmy rate of approximately 35%, resulting in the diagnosis of chronic progressive external ophthalmoplegia. In mitochondrial diseases, the tissue distribution of mitochondria with disease-associated variants in mtDNA should be noted, and it is important to select the affected muscle when performing a biopsy for an accurate diagnosis.

Cerebral Tuberculoma with Mild Posterior Cervical Pain as the Main Symptom Despite Extensive Brain Lesions.

A 59-year-old woman with a diabetes history experienced mild neck pain. A neurological examination revealed only mild neck stiffness. Magnetic resonance imaging showed extensive T2-weighted high-intensity lesions with patchy gadolinium enhancement mainly involving the white matter in the right parietal lobe. A cerebrospinal fluid analysis revealed increased protein levels and pleocytosis. While QuantiFERON-TB Gold was positive, computed tomography (CT) and fluorodeoxyglucose on positron emission tomography-CT of the whole body showed no abnormal accumulation, suggesting tuberculosis. A brain biopsy revealed cerebral tuberculoma. As cerebral tuberculoma can show minimal neurological symptoms despite extensive lesions, a cautious examination and early treatment are required to prevent a devastating prognosis.

[A case of chronic inflammatory demyelinating polyradiculoneuropathy concomitant with acquired von Willebrand syndrome].

We report a case of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) concomitant with acquired von Willebrand syndrome. A 33-year-old man developed motor and sensory polyneuropathy with electrophysiological conduction slowing. At this time, M-protein was absent He was diagnosed with CIDP and received intravenous immunoglobulin and subsequent oral corticosteroids, which resulted in almost complete remission for over 10 years. At the age of 44, he presented with chronic anemia. Laboratory tests and colonoscopy revealed that he had acquired von Willebrand syndrome with monoclonal gammopathy of undetermined significance (IgG lambda type) and colon cancer. Bleeding symptoms were.resolved with intravenous immunoglobulin, but not with supplementation of factor VIII. Shortly after successful excision of the cancer, CIDP and acquired von Willebrand syndrome simultaneously recurred. Intravenous immunoglobulin produced rapid improvement of both neurological and hematological abnormalities. Concurring CIDP and acquired von Willebrand syndrome in the present case may indicate that the conditions have a partly common immunological background including monoclonal gammopathy and a potential common autoantibody-mediated mechanism. Alternatively, dysfunction of von Willebrand factor may increase blood-nerve barrier permeability, inducing the recurrence of CIDP.

A Japanese hereditary spastic paraplegia family with a rare nonsynonymous variant in the SPAST gene.

Spastic paraplegia (SPG) type 4 is an autosomal dominant SPG caused by functional variants in the SPAST gene. We examined a Japanese family with three autosomal dominant SPG patients. These patients presented with typical symptoms of SPG, such as spasticity of the lower limbs. We identified a rare nonsynonymous variant, NM_014946.4:c.1252G>A [p.Glu418Lys], in all three family members. This variant has previously been reported in a Russian SPG family as a "likely pathogenic" variant.5 Ascertainment of additional patients carrying this variant in an unrelated Japanese SPG family further supports its pathogenicity. Molecular diagnosis of SPG4 in this family with hereditary spastic paraplegia is confirmed.

[A case of brain tuberculoma resembling a malignant tumor].

A 35-year-old Sudanese man experienced bitter tastes on the right side of his tongue from January 2012. He was admitted to our hospital in March 2012 because of the appearance of distress, right facial palsy, nausea, and dizziness from late February 2012. A neurological examination revealed Bruns nystagmus, which increased on rightward gaze, as well as total hypoesthesia in the distribution of the maxillary branch of the right trigeminal nerve, moderate right peripheral type facial nerve palsy, and limb ataxia on the right side. Neither muscle weakness nor sensory disturbance was observed. Slight hyperreflexia was noted in the right extremities, and bilateral plantar responses were flexor. He showed wide-based ataxic gait and was unable to do tandem gait. Brain CT scans and magnetic resonance (MR) images revealed a mass lesion in the right pons to the right middle cerebellar peduncle with ring enhancement, suggestive of a "target" sign. Laboratory tests, including hematological and biochemical analyses, tumor markers, and antibodies, had normal values while the tuberculin reaction and QuantiFERON-TB Gold were strongly positive. Cerebrospinal fluid analysis revealed a slight increase in the protein level (76 mg/dl) with a normal cell count (2 per µl), and polymerase chain reaction-based tests and cultures were negative for Mycobacterium tuberculosis three times. Right subclavicular lymph node and right adrenal gland showed accumulation of fluorodeoxyglucose on positron emission tomography-CT, as did the mass lesion in the brainstem. These findings suggested a possibility of a metastatic malignant tumor or extrapleural tuberculoma. Because of the patient's religious belief, we were unable to perform a biopsy of the lymph node, and thus administered anti-tuberculous drugs. With treatment, his neurological symptoms such as facial palsy and ataxia improved steadily except for paradoxical worsening for the initial five days, and the gadolinium-enhanced lesion shrunk markedly. Follow-up MR images demonstrated that the lesions did not expand further for 9 months. From this course of treatment, we diagnosed the patient's tumor as brainstem tuberculoma. Brain tuberculoma sometimes resembles a malignant tumor, and it is therefore challenging to diagnose brainstem tuberculosis in cases without lung lesions. It is important to make a comprehensive diagnosis based on the patient's background, imaging, and course of treatment, and to treat brainstem tuberculoma promptly.

Therapeutic Experience of Progressive Multifocal Leukoencephalopathy Development during Ofatumumab Therapy for Chronic Lymphocytic Leukemia.

A 79-year-old man experienced cognitive impairment and visual field defects during ofatumumab therapy for chronic lymphocytic leukemia refractory to combination chemotherapy. Magnetic resonance imaging revealed T1-weighted low-intensity and T2-weighted high-intensity lesions with patchy gadolinium enhancement in the subcortical white matter. A diagnosis of progressive multifocal leukoencephalopathy was made after the detection of John Cunningham virus (JCV) DNA in his cerebrospinal fluid (CSF). Following plasma exchange and the administration of mirtazapine and mefloquine, the JCV DNA levels in the CSF decreased. However, the patient died 55 days after treatment was initiated. Ofatumumab treatment appears to be associated with the development of progressive multifocal leukoencephalopathy.

Multiple system degeneration with basophilic inclusions in Japanese ALS patients with FUS mutation.

Mutations in the fused in sarcoma gene (FUS) were recently found in patients with familial amyotrophic lateral sclerosis (ALS). The present study aimed to clarify unique features of familial ALS caused by FUS mutation in the Japanese population. We carried out clinical, neuropathological, and genetic studies on a large Japanese pedigree with familial ALS. In six successive generations of this family, 16 individuals of both sexes were affected by progressive muscle atrophy and weakness, indicating an autosomal dominant trait. Neurological examination of six patients revealed an age at onset of 48.2+/-8.1 years in fourth generation patients, while it was 31 and 20 years in fifth and sixth generation patients, respectively. Motor paralysis progressed rapidly in these patients, culminating in respiratory failure within 1 year. The missense mutation c.1561 C>T (p.R521C) was found in exon 15 of FUS in the four patients examined. Neuropathological study of one autopsied case with the FUS mutation revealed multiple system degeneration in addition to upper and lower motor neuron involvement: the globus pallidus, thalamus, substantia nigra, cerebellum, inferior olivary nucleus, solitary nucleus, intermediolateral horn, Clarke's column, Onuf's nucleus, central tegmental tract, medial lemniscus, medial longitudinal fasciculus, superior cerebellar peduncle, posterior column, and spinocerebellar tract were all degenerated. Argyrophilic and basophilic neuronal or glial cytoplasmic inclusions immunoreactive for FUS, GRP78/BiP, p62, and ubiquitin were detected in affected lesions. The FUS R521C mutation in this Japanese family caused familial ALS with pathological features of multiple system degeneration and neuronal basophilic inclusions.

[A case of acute disseminated encephalomyelitis associated with Epstein-Barr virus reactivation during infliximab therapy].

A 31-year-old woman with Crohn's disease that had been refractory to drug therapies for 7 years had been treated with infliximab for a year. She was admitted to our hospital because of truncal ataxia and bulbar palsy, which presented following aseptic meningitis. Neurological examination revealed abducens paresis on the left, gaze-evoked nystagmus on upward and rightward gaze, right facial muscle weakness, bulbar palsy, weakness in the right upper extremity, limb ataxia predominantly on the left side, diminished sense in the lower extremities predominantly on the right, diffuse hyperreflexia in all extremities. Antibodies to Epstein-Barr virus (EBV) in serum demonstrated a previous infection pattern, and EBV-DNA was detected in peripheral blood and cerebrospinal fluid (CSF) by PCR. CSF analysis indicated pleocytosis, an elevation of IgG index and a marked increase in the level of myelin basic protein. FLAIR MRI images revealed multiple hyperintense lesions in the brainstem, subcortical white matter, and cervical spinal cord. Accordingly, we diagnosed her as having acute disseminated encephalomyelitis (ADEM), associated with reactivated EBV infection. Although gancyclovir, plasma exchange and intravenous high dose immunoglobulins were not effective, repetitive use of methylprednisolone pulse therapy alleviated her symptoms and the abnormal MRI lesions. It is suggested that the reactivated EBV infection caused by infliximab may have contributed to the development of ADEM in this case. Besides the demyelinating event directly induced by anti-TNF-alpha therapy, we should pay attention to the occurrence of reactivated EBV-triggered ADEM during anti-TNF-alpha therapy.

[A case of anti-Hu antibody- and anti-GluR epsilon2 antibody-positive paraneoplastic neurological syndrome presenting with limbic encephalitis and peripheral neuropathy].

We report a case of paraneoplastic neurological syndrome with anti-neuronal antibodies, namely anti-Hu and anti-GluR epsilon 2 antibodies in sera. A 72-year-old male had a transient history of eye movement disorder and sensory neuropathy, which improved spontaneously. Two years later, he was admitted to another hospital because of gait disturbance, numbness of the hands and an attack of unconsciousness with generalized convulsion. He was admitted to our hospital with prolonged consciousness disturbance and muscular weakness of all extremities. On admission his consciousness deteriorated slightly without neck stiffness. His cranial nervous system was normal except for incomplete abduction and elevation of both eyes. The patient had severe distal dominant weakness and atrophy in the muscles of all four limbs. Muscle tonus was decreased and hyporeflexia was noted in the four extremities. Plantar response was extensor. Neither sensory disturbance nor ataxia was observed. Cranial MRI showed T2-weighted high intensity lesions in the bilateral mesial temporal lobes, including the hippocampi. A nerve conduction study revealed motor-dominant peripheral neuropathy with prolonged latency; the amplitudes of compound muscle action potentials were severely reduced in all four limbs and those of sensory nerve action potentials were moderately reduced in the right upper and lower extremities. We also found a left hilar lymphadenopathy showing accumulation of FDG on PET, suggesting a possibility of malignancy. Anti-Hu and anti-GluR epsilon 2 antibodies were detected in sera but not in CSF. We diagnosed him with limbic encephalitis and peripheral neuropathy due to paraneoplastic neurological syndrome and treated him with two courses of intravenous immunoglobulin (IVIg) (400 mg/kg, 5 days). The consciousness disturbance, and prolonged distal latency revealed by motor nerve conduction studies improved slightly. Although the roles of anti-neuronal antibodies in paraneoplastic conditions remain unknown, we consider that IVIg may be worth using to treat cases with anti-Hu and anti-GluR epsilon 2 antibodies.

[Sporadic hemiplegic migraine-like headache in a patient with systemic lupus erythematosus].

A 39-year-old woman suddenly developed numbness of the left arm following mild weakness of the left upper and lower extremities, blindness in the left visual field, and difficulty finding words. Her symptoms lasted for two hours with no deficit remaining. Six months after the first episode, the first of several more occurred. Two of the episodes were followed by nausea and a non-pulsative headache around the left temporo-parietal regions and the orbit. She had also been suffering recurrent skin eruptions for the previous two years. There was no family history of migraine. Her neurological symptoms fulfilled the criteria of sporadic hemiplegic migraine (SHM). Biopsy of skin eruption revealed lymphocytic infiltration and liquefied degeneration of basal lamina. These findings were compatible with systemic lupus erythematosus (SLE). There were no lesions evident on brain MR. We diagnosed SLE and after administration of aspirin (100 mg/day) and lomerizine hydrochloride (10 mg/day), her neurological symptom completely disappeared. SHM-like headache in patients with SLE is extremely rare. Although an autoimmune or thrombotic mechanism has been suggested for neurological symptoms in SLE, further studies are needed to elucidate the mechanism. We propose that SLE should be considered as one of the differential diagnoses of SHM.

[Successful treatment of a case of steroid-dependent neuro-Sweet disease with dapsone].

A 35-year-old Japanese man was admitted to our hospital with recurrent meningoencephalitis of unknown etiology. He presented with fever, convulsions and loss of consciousness, which started at age 33. We diagnosed him with neuro-Sweet disease (NSD) based on human leukocyte antigen (HLA) B-54/Cwl positivity and neutrophilic infiltration into the dermis in a biopsied skin plaque. Intravenous methylprednisolone and oral prednisolone markedly improved his fever and CSF pleocytosis. Five years later he was again admitted to our hospital with high fever, oral aphthae and dull-red edematous plaques on the face and body. He was conscious, but he had neck stiffness, mild hyperreflexia in all limbs and an extensor plantar response. Laboratory tests revealed increased white blood cell, erythrocyte sedimentation rate (ESR) and C-reactive protein level. CSF analysis indicated mild pleocytosis. A skin biopsy from an edematous plaque revealed neurotrophils infiltrating the upper dermis. We treated him with intravenous methylprednisolone (1 g/day) for 3 days, followed by oral prednisolone (50 mg/day). His symptoms improved remarkably; however, he had recurrence of symptoms, such as fever, meningial irritation and oral aphtae, with attempted taper of prednisolone. We started treatment with dapsone (75 mg/day) in addition to prednisolone, and could taper oral prednisolone, without a relapse. However, because some mildly recurred with the tapering of dapson, we maintained dapsone treatment at 75 mg daily, added colchicine (1 mg/ day) and tapered only prednisolone. His symptoms were improved and no relapse has been observed. NSD is characterized by neurotrophic hyperactivation and infiltration of tissues. It is highly responsive to systemic corticosteroid therapy; however, some cases show frequent recurrences on tapering of corticosteroids. Dapsone is considered to prevent neurotrophic overactivity. In this case, dapsone was supposed to be effective to prevent reccurence of NSD upon tappering corticosteroids. Dapsone should be a therapeutic options for steroid-dependent NSD showing frequent recurrence.