Anti-Kv1.4 Antibody-positive Nivolumab-induced Myasthenia Gravis and Myositis Presenting with Bilateral Ptosis and Demonstrating Different Pathophysiologies.

Nivolumab blocks inhibitors of T-cell activation and restores antitumor immunity but promotes T-cell activity in host tissues by blocking inhibition of the T-cell function, resulting in immune-related adverse effects. We herein report an 80-year-old man presenting with nivolumab-related myasthenia gravis with anti-muscular voltage-gated potassium channel-complex (Kv1.4) antibodies. On day 29 after nivolumab administration, he simultaneously developed rapidly progressing right ptosis and left facial paralysis. Nivolumab administration was discontinued. He subsequently presented with bulbar paralysis, dyspnea, and muscle weakness and received intravenous immunoglobulin, methylprednisolone, and plasma exchange. The severity of nivolumab-related myasthenia gravis with anti-Kv1.4 antibodies presented with diverse clinical findings.

Magnetic resonance imaging arterial spin labeling hypoperfusion with diffusion-weighted image hyperintensity is useful for diagnostic imaging of Creutzfeldt-Jakob disease.

Background and objectives: Magnetic resonance imaging with arterial spin labeling (ASL) perfusion imaging is a noninvasive method for quantifying cerebral blood flow (CBF). We aimed to evaluate the clinical utility of ASL perfusion imaging to aid in the diagnosis of Creutzfeldt-Jakob disease (CJD). Methods: This retrospective study enrolled 10 clinically diagnosed with probable sporadic CJD (sCJD) based on the National CJD Research & Surveillance Unit and EuroCJD criteria and 18 healthy controls (HCs). Diffusion-weighted images (DWIs), CBF images obtained from ASL, N-isopropyl-(123I)-p-iodoamphetamine (123IMP)-single-photon emission computed tomography (SPECT) images, and 18F-fluorodeoxyglucose (18FDG)-positron emission tomography (PET) images were analyzed. First, the cortical values obtained using volume-of-interest (VOI) analysis were normalized using the global mean in each modality. The cortical regions were classified into DWI-High (≥ +1 SD) and DWI-Normal (< +1 SD) regions according to the DWI-intensity values. The normalized cortical values were compared between the two regions for each modality. Second, each modality value was defined as ASL hypoperfusion (< -1 SD), SPECT hypoperfusion (< -1 SD), and PET low accumulation (< -1 SD). The overall agreement rate of DWIs with ASL-CBF, SPECT, and PET was calculated. Third, regression analyses between the normalized ASL-CBF values and normalized SPECT or PET values derived from the VOIs were performed using a scatter plot. Results: The mean values of ASL-CBF (N = 10), 123IMP-SPECT (N = 8), and 18FDG-PET (N = 3) in DWI-High regions were significantly lower than those in the DWI-Normal regions (p < 0.001 for all); however, HCs (N = 18) showed no significant differences in ASL-CBF between the two regions. The overall agreement rate of DWI (high or normal) with ASL-CBF (hypoperfusion or normal) (81.8%) was similar to that of SPECT (85.2%) and PET (78.5%) in CJD. The regression analysis showed that the normalized ASL-CBF values significantly correlated with the normalized SPECT (r = 0.44, p < 0.001) and PET values (r = 0.46, p < 0.001) in CJD. Discussion: Patients with CJD showed ASL hypoperfusion in lesions with DWI hyperintensity, suggesting that ASL-CBF could be beneficial for the diagnostic aid of CJD.

Magnetic resonance imaging findings of the lower limb muscles in anti-mitochondrial M2 antibody-positive myositis.

Anti-mitochondrial M2 antibody (AMA-M2)-positive myositis is an idiopathic inflammatory myopathy (IIM). Of all patients with myositis, 2.5-19.5% have AMA-M2 antibodies. However, the detailed distribution of muscles affected in AMA-positive myositis is unknown. Therefore, we examined lower muscle magnetic resonance imaging (MRI) findings of patients with AMA-positive myositis. Among the 63 patients with IIM at our institute, 5 (7.9%) were positive for AMA-M2 antibodies. However, one was also positive for anti-Jo1 antibodies; therefore, four patients were finally participated in this study. All patients had high-intensity MRI signals in the proximal muscles, including the gluteus maximus and iliopsoas muscles, and in the thigh muscles, including the vastus lateralis, vastus medialis, adductor magnus, and semimembranosus muscles. Lower leg muscles were relatively spared. Fascial edema was observed in all patients and was also present in the lower leg muscles. Subcutaneous edema was observed, particularly in the proximal portion of the lower limbs. In AMA-positive myositis, proximal muscles, including the gluteus maximus, vastus lateralis, adductor magnus, and the semimembranosus, were markedly affected, while the lower leg muscles were relatively preserved. Additionally, fascial edema was evident even in lower leg muscles. Therefore, muscle MRI can be a useful diagnostic aid for AMA-positive myositis.

[A case of progressive multifocal leukoencephalopathy associated with daratumumab, bortezomib, and dexamethasone for multiple myeloma].

An 83-year-old man presented with visual disturbance and right hemiparalysis, one month after daratumumab, bortezomib, and dexamethasone administration for multiple myeloma (MM). Blood screens revealed a CD4+ T-lymphocyte count of 132/µl. Diffusion weighted and fluid-attenuated inversion-recovery MR imaging showed high intensity signals in the both occipital lobes and left precentral area. The patient had no history of human immunodeficiency virus infection. Cerebrospinal fluid (CSF) JC virus (JCV) was positive (83 copies/ml), as indicated by PCR. The patient was diagnosed with progressive multifocal leukoencephalopathy (PML). MM treatment was discontinued, and mefloquine and mirtazapine therapy was started. However, the CSF JCV-DNA PCR count did not improve (111 copies/ml) after 30 days from starting mefloquine and mirtazapine therapy. The patient died six months after symptom onset. Conclusively, patients with decreased CD4+ T lymphocyte counts following DBd therapy for MM, the possibility of PML should be considered.

Regional cortical hypoperfusion and atrophy correlate with striatal dopaminergic loss in Parkinson's disease: a study using arterial spin labeling MR perfusion.

PURPOSE: To investigate the relationship of the striatal dopamine transporter density to changes in the gray matter (GM) volume and cerebral perfusion in patients with Parkinson's disease (PD). METHODS: We evaluated the regional cerebral blood flow (CBF) and GM volume, concurrently measured using arterial spin labeling and T1-weighted magnetic resonance imaging, respectively, as well as the striatal specific binding ratio (SBR) in 123I-N-ω-fluoropropyl-2ß-carboxymethoxy-3ß-(4-iodophenyl)nortropane (123I-FP-CIT) single-photon emission computed tomography in 30 non-demented patients with PD (15 men and 15 women; mean age, 67.2 ± 8.8 years; mean Hoehn-Yahr stage, 2.2 ± 0.9). Voxel-wise regression analyses using statistical parametric mapping (SPM) were performed to explore the brain regions that showed correlations of the striatal SBR to the GM volume and CBF, respectively, with a height threshold of p < 0.0005 at the voxel level and p < 0.05 family-wise error-corrected at the cluster level. RESULTS: SPM analysis showed a significant positive correlation between the SBR and GM volume in the inferior frontal gyrus (IFG). Whereas, a positive correlation between the SBR and CBF was widely found in the frontotemporal and parietotemporal regions, including the IFG. Notably, the opercular part of the IFG showed significant correlations in both SPM analyses of the GM volume (r2 = 0.90, p < 0.0001) and CBF (r2 = 0.88, p < 0.0001). CONCLUSION: The voxel-wise analyses revealed the brain regions, mainly the IFG, that showed hypoperfusion and atrophy related to dopaminergic loss, which suggests that the progression of dopaminergic neurodegeneration leads to regional cortical dysfunction in PD.

Center of pressure velocities in patients with body lateropulsion: three case report series of Wallenberg's syndrome.

PURPOSE: In patients with Wallenberg's syndrome who present with body lateropulsion (BL), whether the center of pressure (COP) position and velocity characterize postural dysregulation is unknown. We measured time-course changes in COP parameters in three BL patients. METHODS: Three patients with acute Wallenberg's syndrome presented with BL. COP was measured for time-course changes during first standing and every week thereafter. COP positions, which indicate the deviation in the center of gravity, were calculated. COP velocities associated with dynamic movements of the center of gravity were analyzed separately for the BL and non-BL sides. RESULTS: All patients showed that COP position shifted to the BL side in first standing and changed to the center over time. COP velocities to the BL side were fast in first standing. Two of the three patients had significantly faster COP velocities to the BL side than to the non-BL side (p < .05), and one did not. In all three cases, the faster COP velocities to the BL side decreased significantly after 2 weeks compared to the initial standing position (p < .001). The change seemed to be related to the time when independent walking became possible. CONCLUSIONS: Fast COP velocity to the BL side might reflect postural dysregulation in patients with BL. These findings might be useful information for devising effective rehabilitation in patients with BL.

Autoimmune basal ganglia encephalitis associated with anti-recoverin antibodies: A case report.

Autoimmune basal ganglia encephalitis causes neurological symptoms such as parkinsonism associated with basal ganglia lesions. Here, we report a case of autoimmune basal ganglia encephalitis without retinal lesions or malignancy harboring anti-recoverin antibodies. The patient was a 67-year-old Japanese woman who developed anorexia, parkinsonism, and disturbance of consciousness 7 days before admission. Brain magnetic resonance imaging showed hyperintense bilateral basal ganglia lesions on fluid-attenuated inversion recovery images. 18F-fluorodeoxyglucose-positron emission tomography showed no malignancy in the trunk, and dopamine transporter single-photon emission computed tomography with dopamine transporters revealed reduced radiotracer uptake in the basal ganglia. Further, anti-recoverin IgG antibodies were detected in serum immunoblot. Based on the clinical and imaging findings, the patient was diagnosed with autoimmune basal ganglia encephalitis with anti-recoverin antibodies and administered high-dose immunoglobulins (HD-IVIG), which led to an improvement in clinical symptoms. Anti-recoverin antibodies are paraneoplastic antibodies that explicitly bind to Ca2+-binding proteins in the retina and cause retinopathy. This pathological sequence is defined as cancer-associated retinopathy (CAR). However, in our case, autoimmune basal ganglia encephalitis developed without CAR syndrome or malignancy. Clinicians should be aware of the possibility of autoimmune basal ganglia encephalitis showing anti-recoverin antibodies but no CAR syndrome or malignancy, which should be treated with HD-IVIG therapy.

Progressive Encephalomyelitis with Rigidity and Myoclonus (PERM)-like Symptoms Associated with Anti-ganglionic Acetylcholine Receptor Antibodies.

This report describes a 59-year-old woman who presented with progressive encephalomyelitis with rigidity and myoclonus (PERM)-like symptoms and severe dysautonomia, including orthostatic hypotension, sinus bradycardia, dysuria, and prolonged constipation. Her neurological symptoms improved after immunotherapy, but the dysautonomia persisted. Anti-ganglionic acetylcholine receptor (gAChR) α3 subunit antibodies, which are frequently identified in patients with autoimmune autonomic ganglionopathy, were detected in the pre-treatment serum. The central distribution of the nicotinic acetylcholine receptors, a target of anti-gAChR antibodies, and immunotherapeutic efficacy observed in this case indicate that anti-gAChR α3 subunit antibodies are associated with the PERM-like features accompanied by autonomic manifestations.

[A case of asymptomatic Stanford type A aortic dissection with multiple perforator infarcts due to pseudointracavitary thrombus].

A 56-year-old man presented to our hospital as he presented progressive hemiplegia of the right upper limb with no other symptoms, including chest pain. Inter-arm blood pressure difference was not observed. Laboratory investigations revealed an elevated D-dimer value (2.4 µg/ml). Chest X-ray study showed normal findings without widened mediastinum. Brain MRI showed acute multiple brain infarcts in the left posterior limb of the internal capsule and right pons on diffusion-weighted imaging. Bilateral internal carotid arteries were non-occlusive in MRA. Carotid duplex ultrasonography revealed normal internal carotid artery flow velocities bilaterally. Because ischemic lesions were found in multiple vascular territories, and D-dimer value was elevated, the patient underwent thoracic contrast-enhanced-CT to exclude malignant tumors. Stanford type A aortic dissection limited to the ascending aorta was detected. As the plaque had accumulated in the false lumen, we suspected that plaque in the false lumen could be an embolic source. After ascending aortic replacement surgery, brain infarction did not recur during hospitalization. In cases of ischemic stroke wherein multiple vascular territories are detected, and D-dimer value is elevated, even in patients without chest pain, the possibility of painless Stanford type A aortic dissection should be ruled out as an embolic source.

[A case of post-surgical inflammatory neuropathy with lower-extremity weakness after surgery for anorectal malignant melanoma that showed the effectiveness of immunotherapy].

A 59-year-old man with past histories of bronchial asthma and chronic sinusitis underwent transanal resection of anorectal malignant melanoma with general anesthesia. On the third day after surgery, he presented with subacute weakness with right dominant hypoesthesia in the bilateral lower limbs. Tendon reflexes were diminished without pathological reflexes. Blood examination showed increased eosinophils (2,058/µl) and elevated serum immunoglobulin E (675.0 IU/ml). Cerebrospinal fluid examination showed elevated protein (200 mg/dl) without pleocytosis (<5/µl). A nerve conduction study suggested multiple mononeuropathy with motor and axonal dominance in the right tibial, peroneal, and sural nerves. Because of eosinophilia and his past medical history (i.e., bronchial asthma and chronic sinusitis), we initially suspected eosinophilic polyangiitis granulomatosis (EGPA) as the cause of postoperative polyneuropathy. However, his neurological symptoms did not improve despite the decreased eosinophil count after tumor resection, which was inconsistent with EGPA. We biopsied the left sural nerve to exclude EGPA and make a diagnosis. Pathological findings revealed no demyelination, axonal degeneration, or eosinophil infiltration with granuloma formation; however, lymphocyte-dominated inflammation was observed around the epineurial small vessels. Thus, the patient was diagnosed with early onset post-surgical inflammatory neuropathy (PIN) based on his clinical course and the pathological findings. On post-surgery day 48, oral administration of prednisolone (40 mg/day) was started. His neurological symptoms improved quickly and remarkably. Our case suggests that, when multiple mononeuropathy develops early after surgery, PIN should be considered as a differential diagnosis to initiate appropriate treatment based on the pathological condition of neuropathy.

Antibodies to the α3 subunit of the ganglionic-type nicotinic acetylcholine receptors in patients with autoimmune encephalitis.

Since autonomic dysfunction is closely associated with autoimmune encephalitis (AE), the objective of this study was to determine the autonomic symptoms and the prevalence of anti-α3 subunit of the ganglionic-type nicotinic acetylcholine receptor (gAChRα3) antibodies in the patients with AE. We reviewed the clinical features of 19 AE patients, and specifically analyzed sera for anti-gAChRα3 antibodies using the luciferase immunoprecipitation system (LIPS) assay. Cardiovascular autonomic symptoms were found to be common in patients with AE, and hypersalivation was seen only in patients with NMDAR encephalitis. LIPS detected anti-gAChRα3 antibodies in the sera from patients with AE (5/29, 26%). This study is the first to demonstrate that clinical characteristics including autonomic symptoms of AE patients with seropositivity for gAChR autoantibodies. It will be important to verify the role of gAChR antibodies in autonomic dysfunction and brain symptoms to clarify the pathogenesis of AE.

A case of longitudinally extensive transverse myelitis with an isolated pontine lesion following epidural and spinal anesthesia for cesarean section.

Severe neurologic complications following epidural and spinal anesthesia rarely occur. Transverse myelitis has been reported as a rare complication of epidural or spinal anesthesia. We report a case of longitudinally extensive transverse myelitis and an isolated pontine lesion, which responded to immunotherapy. The patient was a 31-year-old pregnant woman who underwent elective cesarean section under epidural and spinal anesthesia. Though the insertions of the epidural and spinal catheters were smooth, she experienced back pain and transient hearing loss during epidural anesthesia. Postoperatively, she exhibited severe motor weakness in both lower extremities, neuralgia below the level of Th10 dermatome, and urinary retention. Magnetic resonance imaging showed longitudinally extensive transverse myelitis from T6 to T10 with a ring-shaped enhanced lesion and an isolated pontine lesion. These findings on magnetic resonance imaging were suggestive of autoimmune diseases such as neuromyelitis optica. The patient was diagnosed with an immunoreactive disease triggered by epidural or spinal anesthesia and was administered high-dose methylprednisolone, which led to the improvement in clinical symptoms. Clinicians should be aware of the possibility of the development of longitudinally extensive transverse myelitis and isolated pontine lesions after cesarean section under epidural and spinal anesthesia.

[Spinal dural arteriovenous fistula presented with rapidly progressive myelopathy, longitudinally extensive spinal cord lesion, pleocytosis with polymorphonuclear predominance, and decreased cerebrospinal fluid glucose levels: a case report].

A 75-year-old woman developed low back pain, weakness of the lower extremities, and urinary retention. On day 7 after the onset of symptoms, she was brought to the emergency department of our hospital by an ambulance because of progressive weakness of both lower extremities. Spine MRI showed longitudinally extensive spinal cord lesion (LESCL) at the Th8-Th11 spinal cord level and flow voids around the lesions. Lumbar puncture revealed a normal opening pressure, yellowish appearance, pleocytosis with polymorphonuclear predominance, and decreased cerebrospinal fluid (CSF) glucose levels. Based on the rapidly progressing myelopathy, LESCL, and CSF findings, we initially diagnosed the patient with myelitis and administered acyclovir and high-dose intravenous immunoglobulin on day 7. Spine MRI with gadolinium-enhancement showed longitudinally extending flow voids of the thoracic cord, and digital subtraction arteriogram (DSA) revealed arteriovenous shunt on the dura with dilated and tortuous intradural veins. We finally diagnosed her with spinal dural arteriovenous fistula (SDAVF). Cases of SDAVF might be initially misdiagnosed as myelitis because of showing rapid progressive myelopathy, pleocytosis with polymorphonuclear predominance, and decreased CSF glucose levels. Lumbar puncture and steroid administration for the cases of SDAVF could aggravate the patient's neurological symptoms. Therefore, lumbar puncture and initiation of immunotherapy should be avoided until SDAVF is completely excluded in patients with suspected myelitis on spine MRI without gadolinium-enhancement, even if their neurological symptoms progress rapidly.

An autopsy case of tuberculous meningitis undiagnosed by nested-PCR of CSF samples and brain biopsy.

Nested polymerase chain reaction (PCR) testing of cerebrospinal fluid (CSF) has higher diagnostic sensitivity with regard to tuberculous meningitis (TBM) than conventional methods. Herein we describe the autopsy case of a 70-year-old woman with TBM that could not be diagnosed via nested PCR in CSF, even though it was performed three times. The clinical course, magnetic resonance imaging results, and elevated adenosine deaminase levels in CSF were consistent with TBM. We also performed a brain biopsy from the thickened leptomeninges of the patient, which showed granulomatous leptomeningitis consistent with TBM. However, we were not able to identify tuberculous bacilli by the acid-fast bacterial staining, single PCR test, and culture of the biopsy preparations. We finally diagnosed TBM in this case by the positive results of both the fourth PCR test and culture of her CSF, which were taken 7 days before her death. This case suggests that even the combination of repetitive nested PCR in CSF and brain biopsy lacks adequate sensitivity to exclude TBM in some patients.

[Progressive Multifocal Leukoencephalopathy Associated with HIV Infection Diagnosed by Brain Biopsy with Repeated Negative PCR Testing of CSF JC Virus DNA].

A 36-year-old man with human immunodeficiency virus (HIV) infection was admitted to our hospital due to progressive ataxia. Brain MRI demonstrated high-signal intensity in the white matter of the right parietal lobe and left cerebellar hemisphere on T2-weighted images. Despite antiretroviral therapy, as his clinical symptoms worsened and MRI lesions gradually increased with the appearance of gadolinium-enhanced lesions, immune reconstitution inflammatory syndrome by progressive multifocal leukoencephalopathy (PML) associated with HIV infection was suspected. However, JC virus (JCV) in the cerebrospinal fluid (CSF) was undetectable by DNA PCR twice. Therefore, biopsy of the right parietal lobe was performed. JCV DNA was detected by PCR using the biopsy sample. JC viral protein was also identified by immunohistochemistry. Brain biopsy should be considered for the clinical diagnosis of PML when CSF JCV is negative on repeated DNA PCR. (Received September 20, 2019; Accepted January 14, 2020; Published May 1, 2020).

Autoimmune Encephalitis Associated with Anti-gamma-aminobutyric Acid B Receptor Antibodies Mimicking Syncope.

Autoimmune encephalitis associated with autoantibodies to the gamma-aminobutyric acid B receptor (GABABR-AE) typically involves limbic symptoms with limbic abnormalities visible in brain magnetic resonance imaging (MRI). We herein report a case of a 48-year-old man with GABABR-AE whose initial presentation was limited to syncope without limbic symptoms or MRI abnormalities. Interestingly, serial MRI also revealed no abnormalities even after the appearance of limbic symptoms. Our findings suggest that GABABR-AE can initially mimic common syncope and that MRI findings may remain normal throughout the clinical course. Even if patients have normal MRI findings, GABABR-AE should be considered if limbic symptoms worsen.

Cladophialophora bantiana infection mimicking neuromyelitis optica.

Cladophialophora bantiana (C. bantiana) is a life-threatening melanized mycelial fungus causing brain abscess. C. bantiana is usually observed in tropical countries, including India. We report a Japanese case of C. bantiana presenting with myelitis mimicking neuromyelitis optica (NMO) and brain abscess. A 73-year-old man was administered prednisolone (30 mg/day) for antineutrophil cytoplasmic antibody (ANCA)-related vasculitis 100 days before admission. He had right side-dominant paraplegia and sensory loss in the right leg. T2-weighted spinal cord MRI revealed longitudinal high-intensity signals at the T7 to T12 levels. A ring-enhancing lesion at the T10 level was detected on gadolinium (Gd)-enhanced MRI. He was tentatively diagnosed with NMO, and steroid pulse therapy was performed. One month later, an abscess at the right cerebropontine angle was noted on Gd-enhanced brain MRI. Two months later, several subcutaneous intramuscular tumors were detected. Based on the morphological study of the cultured organelle obtained by tumor enucleation and the internal transcribed spacer sequence of ribosomal RNA, the pathogen was identified as C. bantiana. Although he received liposomal amphotericin B treatment, the patient died of respiratory insufficiency. C. bantiana infection should be considered in patients with myelitis presenting with longitudinal lesions and CNS abscess in an immunocompromised state.

Arterial spin labeling MR imaging for the clinical detection of cerebellar hypoperfusion in patients with spinocerebellar degeneration.

PURPOSE: The aim of this study was to evaluate the clinical utility of arterial spin labeling (ASL) magnetic resonance imaging (MRI) for the detection of cerebellar hypoperfusion in patients with spinocerebellar degeneration (SCD). METHODS: Regional cerebral blood flow (CBF) were obtained from ASL and 123I-IMP single-photon emission computed tomography (SPECT) images by volume-of-interest analysis in patients with SCD (n = 16). Regional CBF were also measured by ASL in age-matched controls (n = 19) and by SPECT in separate controls (n = 17). The cerebellar CBF values were normalized to the CBF values for the whole gray matter (nCBF) in ASL and SPECT. RESULTS: The mean cerebellar nCBF measured by ASL was lower in patients with SCD (0.70 ±â€¯0.09) than in the controls (0.91 ±â€¯0.05) (p < 0.001), which was consistent with the comparison using SPECT (0.82 ±â€¯0.05 vs. 0.98 ±â€¯0.05, p < 0.001). The cerebellar nCBF measured by ASL significantly correlated with that determined by SPECT in patients (r = 0.56, p < 0.001). CONCLUSIONS: ASL imaging showed decreased cerebellar blood flow, which correlated with that measured by SPECT, in patients with SCD. These findings suggest the clinical utility of noninvasive MRI with ASL for detecting cerebellar hypoperfusion in addition to atrophy, which would aid the diagnosis of SCD.