Akiko Tamasaki

Ambroxol chaperone therapy for neuronopathic Gaucher disease: A pilot study

Gaucher disease (GD) is a lysosomal storage disease characterized by a deficiency of glucocerebrosidase. Although enzyme‐replacement and substrate‐reduction therapies are available, their efficacies in treating the neurological manifestations of GD are negligible. Pharmacological chaperone therapy is hypothesized to offer a new strategy for treating the neurological manifestations of this disease. Specifically, ambroxol, a commonly used expectorant, has been proposed as a candidate pharmacological chaperone. The purpose of this study was to evaluate the safety, tolerability, and neurological efficacy of ambroxol in patients with neuronopathic GD.

Early predictors of status epilepticus-associated mortality and morbidity in children

BACKGROUNDnEarly predictors of status epilepticus (SE)-associated mortality and morbidity have not been systematically studied in children, considerably impeding the identification of patients at risk.nnnOBJECTIVESnTo determine reliable early predictors of SE-associated mortality and morbidity and identify the etiology of SE-associated sequelae in Japanese children.nnnMETHODSnWe conducted a prospective multicenter study of clinical findings and initial laboratory data acquired at SE onset, and assessed outcomes at the last follow-up examination. In-hospital death during the acute period and neurological sequelae were classified as poor outcomes.nnnRESULTSnOf the 201 children who experienced their first SE episode, 16 exhibited poor outcome that was most commonly associated with acute encephalopathy. Univariate analysis revealed that the following were associated with poor outcomes: young age (⩽24 months); seizure duration >90 min; seizure intractability (failure of the second anticonvulsive drug); biphasic seizures; abnormal blood glucose levels (<61 or >250 mg/dL); serum aspartate aminotransferase (AST) ⩾56 U/L; and C-reactive protein (CRP) levels >2.00 mg/dL. Multivariate analysis revealed that young age, seizure intractability, abnormal blood glucose levels, and elevated AST and CRP levels were statistically significant.nnnCONCLUSIONSnYoung age and seizure intractability were highly predictive of poor outcomes in pediatric SE. Moreover, abnormal blood glucose levels and elevated AST and CRP levels were predictors that might be closely associated with the etiology, especially acute encephalopathy and severe bacterial infection (sepsis and meningitis) in Japanese children.

An association of 19p13.2 microdeletions with Malan syndrome and Chiari malformation

Patients with microdeletions in the 19p13.2 chromosomal region show developmental delays, overgrowth, and distinctive features with big head appearances. These manifestations are now recognized as Sotos syndrome‐like features (Sotos syndrome 2) or Malan syndrome. We identified three female patients with 19p13.2 deletions involving NFIX, a gene responsible for Malan syndrome. We compared the genotypic and phenotypic data of these patients with those of the patients previously reported. The most of the clinical features were found to overlap; however, Chiari malformation type I was observed in two of the three patients evaluated in this study. Because Chiari malformation type I has never been reported in the patients with NSD1‐related Sotos syndrome, this finding indicates the possible role of 19p13.2 deletion in patients with mimicking features of Sotos syndrome but have negative NSD1 testing results.

Novel compound heterozygous mutations of POLR3A revealed by whole-exome sequencing in a patient with hypomyelination.

OBJECTIVEnCongenital white matter disorders are a heterogeneous group of hypomyelination disorders affecting the white matter of the brain. Recently, mutations in the genes encoding the subunits of RNA polymerase III (Pol III), POLR3A and POLR3B, have been identified as new genetic causes for hypomyelinating disorders.nnnMETHODnWhole-exome sequencing was applied to identify responsible gene mutations in a 29-year-old female patient showing hypomyelination of unknown cause. To investigate the pathological mechanism underlying the hypomyelination in this patient, the expression level of 7SL RNA, a transcriptional target of Pol III, was analyzed in cultured skin fibroblasts derived from the patient with POLR3A mutations.nnnRESULTSnNovel compound heterozygous mutations of POLR3A were identified in the patient, who started to show cerebellar signs at 3 years, lost ambulation at 7 years, and became bedridden at 18 years. Brain magnetic resonance imaging showed severe volume loss in the brainstem, the cerebellum, and the white matter associated with hypomyelination. In addition to hypodontia and hypogonadism, she showed many pituitary hormone-related deficiencies. The expression level of 7SL RNA in cultured skin fibroblasts derived from this patient showed no significant abnormality.nnnCONCLUSIONnThe many pituitary hormone-related deficiencies identified in this patient may be an essential finding for the Pol III-related leukodystrophies spectrum. Further investigation is needed for a better understanding of the disease mechanism.

Effects of donepezil and serotonin reuptake inhibitor on acute regression during adolescence in Down syndrome

A 14-year-old boy with Down syndrome (DS) showed a gradual decline in his daily activities and feeding capacities, and a marked deterioration triggered by a streptococcal infection was observed at the age of 15 years. He became bedridden, accompanied by sleep disturbance, sustained upward gaze, and generalized rigidity. Magnetic resonance imaging showed unremarkable findings, but antiglutamate receptor autoantibodies were positive in his cerebrospinal fluid. Treatment with thiamine infusion and steroid pulse therapy showed little effect, but gross motor dysfunction and appetite loss were ameliorated by the administration of l-DOPA and serotonin reuptake inhibitors. Thereafter, autistic behaviors predominated, including loss of social interaction, oral tendency, water phobia, and aggressiveness. Initiation of donepezil, an acetylcholinesterase inhibitor, resulted in the disappearance of these symptoms and total recovery of the patient to his previous psychosocial levels. We hypothesize that the acute regression in adolescence represents a process closely related to the defects of serotonergic and cholinergic systems that are innate to DS brains and not just a nonspecific comorbidity of depression or limbic encephalitis.

Abnormal pupillary light reflex with chromatic pupillometry in Gaucher disease

The hallmark of neuronopathic Gaucher disease (GD) is oculomotor abnormalities, but ophthalmological assessment is difficult in uncooperative patients. Chromatic pupillometry is a quantitative method to assess the pupillary light reflex (PLR) with minimal patient cooperation. Thus, we investigated whether chromatic pupillometry could be useful for neurological evaluations in GD. In our neuronopathic GD patients, red light‐induced PLR was markedly impaired, whereas blue light‐induced PLR was relatively spared. In addition, patients with non‐neuronopathic GD showed no abnormalities. These novel findings show that chromatic pupillometry is a convenient method to detect neurological signs and monitor the course of disease in neuronopathic GD.

Risk factors for acute pancreatitis in patients with severe motor and intellectual disabilities

Acute pancreatitis in patients with severe motor and intellectual disability (SMID) is a rare but life‐threatening condition. Possible causes of acute pancreatitis in these patients including valproic acid therapy, hypothermia and nasoduodenal tube feeding, have not yet been investigated in detail. The aim of this study was therefore to investigate the risk factors for acute pancreatitis in patients with SMID.

Effect of levetiracetam in acute encephalitis with refractory, repetitive partial seizures during acute and chronic phase

AIMnTo clarify the effect of levetiracetam (LEV) for acute and chronic seizure control in acute encephalitis with refractory, repetitive partial seizures (AERRPS).nnnMETHODSnWe retrospectively reviewed the clinical course of six AERRPS cases treated with LEV, and explored the acute phase termination by withdrawal from barbiturate-induced coma under artificial ventilation, and the reduction in seizure frequency during the chronic phase. LEV was administrated orally or via nasogastric tubes as an add-on agent during acute (n=3; age 8-10 years) and chronic (n=3; age 19-30 years) AERRPS.nnnRESULTSnIn the acute phase, administration of LEV (50-60 mg/kg/d) in combination with phenobarbital (n=3; peak 57.9-76.1 μg/ml) and potassium bromide (n=2; 30-36 mg/kg/d)) resulted in successful reduction of intravenous barbiturate dosage and withdrawal from artificial ventilation. In the chronic phase, seizure frequency reduced by >75% for 5-18 months with LEV 750-1500 mg/d.nnnCONCLUSIONnLEV may affect seizure control in AERRPS, particularly during the chronic phase, through its unique action of inhibition of excitatory neurotransmitter release. The regimen of oral barbiturate, potassium bromide and LEV would be worth for trial during the acute phase of AERRPS.

Evolution of a symptomatic diffuse developmental venous anomaly with progressive cerebral atrophy in an atypical case of Sturge-Weber syndrome

A 2-year-old boy had glaucoma, bilateral facial haemangioma and widespread blue nevi on the trunk and extremities since birth. Dilated medullary veins were detected in the left cerebral periventricular white matter on magnetic resonance imaging (MRI). Macrocephaly and delayed psychomotor development were observed during late infancy, and susceptibility-weighted angiography revealed an extensive developmental venous anomaly with multiple caput medusae throughout bilateral hemispheres, accompanied by periventricular hyperintense alterations on MRI and progressive diffuse atrophy of the cerebral mantle with left-sided predominance. Hypoperfusion in the left cerebral and cerebellar hemisphere was also uncovered. No meningeal haemangioma was observed. This patient may represent a novel subgroup of phakomatosis cases that can be regarded as a variant of Sturge-Weber syndrome.

Effect of Intrathecal Baclofen on Delayed-Onset Paroxysmal Dystonia due to Compression Injury Resulting From Congenital and Progressive Spinal Bone Deformities in Chondrodysplasia Punctata

BACKGROUNDnDystonia due to spinal lesions in adult patients is characterized by the provocation and/or amelioration of the spasm by somatosensory stimulation with a sensory trick.nnnPATIENT DESCRIPTIONnAn infant with brachytelephalangic chondrodysplasia punctata developed flaccid tetraplegia due to cervical cord compression resulting from congenital atlantoaxial dislocation. Episodic, tonic extension of the extremities, neck, and trunk had appeared daily since age twoxa0years and was often provoked by tactile stimulation. Although decompression surgery was performed at age threexa0years, progressive spinal deformity resulted in the aggravation of episodic dystonia thereafter, lasting for hours. Foot dorsiflexion and wearing a truncal brace for scoliosis inhibited these spasms. Intrathecal baclofen bolus injection transiently ameliorated the paroxysmal dystonia and detrusor-sphincter dyssynergia in the lower urinary tract.nnnCONCLUSIONnParoxysmal dystonia is unusual in children with spinal cord lesions; however, it should be recognized for appropriate individualized clinical management.