Somatosensory pathway dysfunction in patients with amyotrophic lateral sclerosis in a completely locked-in state.

OBJECTIVE: To investigate somatosensory pathway function in patients with amyotrophic lateral sclerosis (ALS) dependent on invasive ventilation and in a completely locked-in state (CLIS). METHODS: We examined median nerve somatosensory evoked potentials (SEPs) in 17 ALS patients in a CLIS, including 11 patients with sporadic ALS, one with familial ALS with genes not examined, four with a Cu/Zn superoxide-dismutase-1 (SOD1) gene variant (Val118Leu, Gly93Ser, Cys146Arg), and one with a fused-in-sarcoma gene variant (P525L). We evaluated N9, N13, N20 and P25, and central conduction time (CCT); the data were compared with those of 73 healthy controls. RESULTS: N20 and N13 were abolished in 12 and 10 patients, and their latencies was prolonged in four and three patients, respectively. The CCT was prolonged in five patients with measurable N13 and N20. Two patients with SOD1 gene mutations had absent or slightly visible N9. Compared to the CCT and latencies and amplitudes of N13 and N20 in the controls, those in the patient cohort were significantly abnormal. CONCLUSIONS: The central somatosensory pathway is severely involved in patients with ALS in a CLIS. SIGNIFICANCE: Our findings suggest that median nerve SEP cannot be utilized for communication in patients with ALS in a CLIS.

Differential immunophenotypes of neuronal cytoplasmic inclusions in the dentate gyrus of multiple system atrophy and their association with clinicopathological features.

Although hippocampal pathologies of multiple system atrophy (MSA) and their association with dementia have been reported, no studies have reported clinicopathological differences among MSA patients with and without neuronal cytoplasmic inclusions (NCIs) in the dentate gyrus (dntNCIs). We investigated hippocampal NCI pathology in 18 MSA patient autopsies, focusing on phosphorylated α-synuclein (pAS)- and phosphorylated tau (pT)-positive dntNCIs. There were 8 MSA patients without and 10 with dntNCIs. The latter group was subclassified by immunophenotype: those with pAS-positive dntNCIs (pAS-dntNCI subtype), those with pT-positive dntNCIs (pT-dntNCI subtype), and those with both types of dntNCIs. MSA patients with dntNCIs survived longer with prolonged tracheostomy and had dementia more frequently than those without dntNCIs. The brain weights of patients with dntNCIs were lower than those without dntNCIs. The presence of dementia was similar among the dntNCI subtypes. The pAS-dntNCI subtype was associated with longer survival and smaller brain weights; the pT-dntNCI subtype exhibited more frequent tau pathologies than the pAS-dntNCI subtype. Thus, MSA with dntNCIs is a possible pathological subtype of longer survivors that correlates with longer disease duration, prolonged tracheostomy, and high frequency of dementia. Understanding clinicopathological differences in MSA patients with and without dntNCIs may lead to improved personalized management strategies.

[Effect of laryngeal closure on recurrent aspiration pneumonia in patients with neurodegenerative disease].

Three patients with neurodegenerative diseases who had developed repeated aspiration pneumonia underwent laryngeal closure, a surgical procedure at the larynx to prevent aspiration. None of these patients have developed aspiration pneumonia since the procedure. One patient needed endoscopic suction and cough assist machine to clear thick sputum, because tracheostomy bypassed the upper airway and so prevented moisturization of inhaled air. While two patients achieved freedom from tracheal cannulation, one needed continued cannulation because of narrowing of the stoma due to improvements in the nutritional condition. One patient was able to resume oral intake. Although the right timing to perform the procedure and optimal care along with long-term observation are important, laryngeal closure is an effective option for patients with neurodegenerative diseases to prevent recurrent aspiration pneumonia.

Clinicopathological characteristics of patients with amyotrophic lateral sclerosis resulting in a totally locked-in state (communication Stage V).

In the present study, we performed a comprehensive analysis to clarify the clinicopathological characteristics of patients with amyotrophic lateral sclerosis (ALS) that had progressed to result in a totally locked-in state (communication Stage V), in which all voluntary movements are lost and communication is impossible. In 11 patients, six had phosphorylated TAR DNA-binding protein 43 (pTDP-43)-immunoreactive (ir) neuronal cytoplasmic inclusions (NCI), two had fused in sarcoma (FUS)-ir NCI, and three had copper/zinc superoxide dismutase (SOD1)-ir NCI. The time from ALS onset to the need for tracheostomy invasive ventilation was less than 24 months in ten patients. Regardless of accumulated protein, all the patients showed common lesions in the pallido-nigro-luysian system, brainstem reticular formation, and cerebellar efferent system, in addition to motor neurons. In patients with pTDP-43-ir NCI, patients with NCI in the hippocampal dentate granule neurons (DG) showed a neuronal loss in the cerebral cortex, and patients without NCI in DG showed a preserved cerebral cortex. By contrast, in patients with FUS-ir NCI, patients with NCI in DG showed a preserved cerebral cortex and patients without NCI in DG showed marked cerebral degeneration. The cerebral cortex of patients with SOD1-ir NCI was preserved. Together, these findings suggest that lesions of the cerebrum are probably not necessary for progression to Stage V. In conclusion, patients with ALS that had progressed to result in communication Stage V showed rapidly-progressed symptoms, and their common lesions could cause the manifestations of communication Stage V.

A Japanese patient with familial ALS and a p.K510M mutation in the gene for FUS (FUS) resulting in the totally locked-in state.

We describe a Japanese patient with familial amyotrophic lateral sclerosis (ALS) and a p.K510M mutation in the fused in sarcoma gene (FUS). The patient's condition was characterized clinically by an early onset and rapid progression. The patient eventually required mechanical ventilation and progressed to the totally locked-in state. Neuropathologically, multiple system degeneration with many FUS-immunoreactive structures was observed. The involvement of the globus pallidus, subthalamic nucleus, substantia nigra, cerebellar efferent system, and both upper and lower motor neurons in the present patient was comparable to that described for ALS patients with different mutations in FUS, all of whom progressed to the totally locked-in state. However, the patient also exhibited degeneration of the cerebellar afferent system and posterior column. Furthermore, the appearance of non-compact FUS-immunoreactive neuronal cytoplasmic inclusions and many FUS-immunoreactive glial cytoplasmic inclusions were unique to the present patient. These features suggest that the morphological characteristics of the FUS-immunoreactive structures and distribution of the lesions vary with the diversity of mutations in FUS.

Familial ALS with FUS P525L mutation: two Japanese sisters with multiple systems involvement.

We evaluated the clinicopathological features of familial amyotrophic lateral sclerosis (ALS) with the fused in sarcoma (FUS) P525L mutation. Two sisters and their mother had a similar clinical course, which was characterized by the development of limb weakness at a young age with rapid disease progression. An elder sister, patient 1, progressed into a totally locked-in state requiring mechanical ventilation and died 26 years after the onset of the disease. In contrast, the younger sister, patient 2, died in the early stages of the disease. The patients had neuropathological findings that indicated a very active degeneration of motor neurons and multiple system degeneration, which led to marked brain and spinal cord atrophy in the long term clinical outcome. The multiple system degeneration included the frontal lobe, the basal ganglia and substantia nigra, cerebellum and related area. Compared with previously reported ALS cases, the severe degeneration of the frontal lobe and the striatum were the characteristic features in the patient 1 in this case study. The degeneration spread over multiple systems might be caused not only by the appearance of the FUS immunoreactive neuronal cytoplasmic inclusions but also by the degeneration of neuronal connections from the primary motor cortex and related areas.

[Neuropathological findings of non-herpetic limbic encephalitis].

In Japan,acute encephalitis similar to herpes simplex encephalitis (HSE) but with no evidence of herpes simplex virus (HSV) infection has been reported. Recently,this type of acute encephalitis has been termed as non-herpetic limbic encephalitis (NHLE) and is indicated to be a possible new subgroup of limbic encephalitis. Only 3 autopsy cases of NHLE have been reported because most patients had a good clinical outcome. However,the 3 autopsy patients who were diagnosed with NHLE on the basis of their typical clinical course died of complications. The neuropathological findings in these 3 cases were similar in that the lesions were exclusively limited to the hippocampus and amygdala. The macroscopic findings in their brains were unremarkable, except for mild swelling. No leptomeningitis, hemorrhagic necrosis, or evidence of any etiologic agent was detected microscopically. The rostral portion of the hippocampus showed small foci characterized by neuronal loss with neuronophagia coexisting with proliferation of microglias, macrophages, hypertrophic astrocytes, and a few lymphocytes. The caudal portion of the hippocampus and amygdala showed neuronal loss with astrocytosis and lymphocytic perivascular cuffing. The abnormal high intensity areas seen on the magnetic resonance imaging scans corresponded well with the regions with astrocytosis. These findings are more similar to those in the case of autoimmune limbic encephalitis than those in the case of HSE. It is likely that these mild neuropathological changes in the case of NHLE are reflective of a good clinical outcome.

Acute limbic encephalitis: a new entity?

Clinical cases similar to herpes simplex virus (HSV) encephalitis have accumulated in Japan. Detailed examinations have failed to demonstrate HSV infection. Recently, these cases have been named "non-herpetic acute limbic encephalitis". Only a single autopsy case was so far reported in an abstract form, because many cases showed a good prognosis. The case presented here was that following fever, a 59-year-old woman developed disturbance of consciousness and uncontrollable generalized seizures. Brain MRI revealed abnormal signals in the bilateral medial temporal lobe and along the lateral part of the putamen. Autoantibody against the NMDA glutamate receptor (GluR) IgM-epsilon2 was detected in the serum, and the GluR IgG-delta2 antibody was positive in cerebrospinal fluid. She died 12 days after onset. An autopsy examination revealed scattered foci consisting of neuronal loss, neuronophagia and some perivascular lymphocytic infiltration in the hippocampus and amygdala, but no haemorrhagic necrosis in the brain. HSV-1, -2 and human herpes virus-6 were negative immunohistochemically. We believe that our autopsy case may contribute to understanding the neuropathological background of non-herpetic acute limbic encephalitis.