Masahiro Nishiyama

A novel PIGN mutation and prenatal diagnosis of inherited glycosylphosphatidylinositol deficiency.

Glycosylphosphatidylinositol (GPI) anchors tether proteins to the extracellular face of eukaryotic plasma membranes. Defects in the human GPI anchor biosynthetic pathway cause inherited GPI deficiencies (IGDs) characterized by multiple congenital anomalies: dysmorphic faces, developmental delay, hypotonia, and epilepsy. We report the case of a 6‐year‐old boy with severe psychomotor developmental delay, epilepsy, and decreased granulocyte surface expression of GPI‐anchored protein that suggested autosomal recessive GPI deficiency. The case underwent target exome sequencing to screen for IGDs. Target exome sequencing of the proband identified an apparently homozygous c.808T > C (p.Ser270Pro) mutation in PIGN, a gene involved in the GPI anchor biosynthetic pathway. As his parents were expecting another child, genetic carrier screening was conducted for the parents. Direct sequencing of the parents identified a heterozygous c.808T > C PIGN mutation in the father but none in the mother. To identify the mothers mutation, we performed semi‐quantitative real‐time PCR of the PIGN exons and long PCR, identifying a microdeletion in PIGN (del exons 2–14). The proband had inherited this microdeletion from his mother. Prenatal diagnosis of the fetus revealed that it was a heterozygous carrier of the mothers pathogenic allele. Here, we report a sporadic case of inherited GPI deficiency with a PIGN mutation and the first case of prenatal diagnosis for GPI deficiency.

Somatic mosaicism of a CDKL5 mutation identified by next-generation sequencing.

INTRODUCTION CDKL5-related encephalopathy is an X-linked dominantly inherited disorder that is characterized by early infantile epileptic encephalopathy or atypical Rett syndrome. We describe a 5-year-old Japanese boy with intractable epilepsy, severe developmental delay, and Rett syndrome-like features. Onset was at 2 months, when his electroencephalogram showed sporadic single poly spikes and diffuse irregular poly spikes. METHODS We conducted a genetic analysis using an Illumina® TruSight™ One sequencing panel on a next-generation sequencer. RESULTS We identified two epilepsy-associated single nucleotide variants in our case: CDKL5 p.Ala40Val and KCNQ2 p.Glu515Asp. CDKL5 p.Ala40Val has been previously reported to be responsible for early infantile epileptic encephalopathy. In our case, the CDKL5 heterozygous mutation showed somatic mosaicism because the boys karyotype was 46,XY. The KCNQ2 variant p.Glu515Asp is known to cause benign familial neonatal seizures-1, and this variant showed paternal inheritance. CONCLUSIONS Although we believe that the somatic mosaic CDKL5 mutation is mainly responsible for the neurological phenotype in the patient, the KCNQ2 variant might have some neurological effect. Genetic analysis by next-generation sequencing is capable of identifying multiple variants in a patient.

Targeted temperature management of acute encephalopathy without AST elevation

BACKGROUND Acute encephalopathy is a leading cause of mortality and neurological sequelae in children. Although many strategies have been proposed, effective therapies have not yet been established. The objective of this retrospective study was to assess the effectiveness of targeted temperature management in children with acute encephalopathy. METHODS We retrospectively evaluated the clinical courses and outcomes of 57 children who were consecutively admitted at Kobe Childrens Hospital between October 2002 and August 2011. These children had acute encephalopathy with serum aspartate aminotransferase (AST) levels below 90 IU/l within 6h of onset. We compared the clinical characteristics and neurological outcomes of children treated with targeted temperature management and those who received conventional care. Targeted temperature management was defined as temperature control (34.5-36°C) with intubation, and the continuous use of anticonvulsants and muscle relaxants induced within 24 h of onset. Outcome was measured using the Pediatric Cerebral Performance Category Scale with grade 1 representing a good clinical outcome and grades 2-6 reflecting poor outcomes. RESULTS Outcomes were good in all children treated with targeted temperature management (n=23) as well as in 24 out of the 34 children who received conventional care (p=0.004). The age, gender, refractory status epilepticus rate, prolonged neurological abnormality rate, preceding infection rate, and laboratory results were not significantly different between the two groups. CONCLUSIONS We determined that targeted temperature management could improve outcome in acute encephalopathy without AST elevation.

Demographics and Outcomes of Patients With Pediatric Febrile Convulsive Status Epilepticus

BACKGROUND Convulsive status epilepticus with fever is common and may be related to neurological sequela in children. However, there are limited data on the demographics and risk factors of this phenomenon. Thus, we aimed to describe the demographics and risk factors of neurological sequela among children with convulsive status epilepticus with fever. METHODS We reviewed convulsive status epilepticus with fever cases in the pediatric intensive care unit at Kobe Childrens Hospital between 2002 and 2013. We included patients with intrinsic neurological disease, and excluded those with obvious central nervous system infection. Cases of neurological worsening were categorized as poor outcome using the pediatric cerebral performance category scale. Possible risk factors for poor outcome included age, sex, neurological medical history, seizure duration, body temperature, and level of consciousness. RESULTS A total of 253 patients (128 males), aged 1 month to 15 years (mean 45 ± 40 months), were enrolled. Three patients (1.2%) died during hospitalization, and 32 (12.6%) patients had a poor outcome. A univariate analysis identified male sex, absence of epilepsy history, body temperature above 40°C on admission, seizure duration longer than 120 minutes, impaired consciousness at 12 hours after onset, and presence of nonconvulsive seizure as potential predictors of poor outcome. A multivariate analysis, revealed that an absence of epilepsy history (odds ratio = 11.18), body temperature above 40°C on admission (odds ratio = 3.39), or impaired consciousness at 12 hours after onset (odds ratio = 41.85) was associated with poor outcome. CONCLUSIONS Our study indicated that absence of epilepsy history, high temperature, and/or prolonged impaired consciousness were associated with brain injury.

Rituximab treatment for relapsed opsoclonus-myoclonus syndrome.

INTRODUCTION Opsoclonus-myoclonus syndrome (OMS) is a rare neurological disorder that is associated with paraneoplastic diseases. Because OMS can frequently relapse, patients may be inflicted with neurological problems for a long time. Recently, rituximab (RTX) was introduced as a drug to treat OMS. To assess RTX treatment, we studied a patient who experienced recurrence of OMS. CASE REPORT A 2-year-old Japanese boy, who had left adrenal neuroblastoma, suddenly showed OMS symptoms, including ataxia and opsoclonus. Surgical resection of the tumor and subsequent steroid therapy ameliorated his symptoms. When OMS relapsed during the time when prednisolone was reduced, he was treated with full-dose RTX therapy (375 mg/m2/week) for 4 consecutive weeks. However, 1year later, he presented again with OMS symptoms. This time, we only administered an additional single dose of RTX treatment (375 mg/m2), allowing remission of OMS symptoms. During 2 years after the additional RTX treatment, OMS symptoms did not appear, even when prednisolone was reduced. He had no adverse events associated with RTX during the whole treatment period. CONCLUSIONS An additional single-dose RTX therapy might be effective for relapsed OMS patients who were previously treated with full-dose RTX therapy.

Next-generation sequencing discloses a nonsense mutation in the dystrophin gene from long preserved dried umbilical cord and low-level somatic mosaicism in the proband mother.

Duchene muscular dystrophy (DMD) is a progressive muscle wasting disease, caused by mutations in the dystrophin (DMD) on the X chromosome. One-third of patients are estimated to have de novo mutations. To provide in-depth genetic counseling, the comprehensive identification of mutations is mandatory. However, many DMD patients did not undergo genetic diagnosis because detailed genetic diagnosis was not available or their mutational types were difficult to identify. Here we report the genetic testing of a sporadic DMD boy, who died >20 years previously. Dried umbilical cord preserved for 38 years was the only available source of genomic DNA. Although the genomic DNA was severely degraded, multiplex ligation-dependent probe amplification analysis was performed but no gross mutations found. Sanger sequencing was attempted but not conclusive. Next-generation sequencing (NGS) was performed by controlling the tagmentation during library preparation. A nonsense mutation in DMD (p.Arg2095*) was clearly identified in the proband. Consequently, the identical mutation was detected as an 11% mosaic mutation from his healthy mother. Finally, the proband’s sister was diagnosed as a non-carrier of the mutation. Thus using NGS we have identified a pathogenic DMD mutation from degraded DNA and low-level somatic mosaicism, which would have been overlooked using Sanger sequencing.

Short and long-term outcomes in children with suspected acute encephalopathy

BACKGROUND The time-dependent changes that occur in children after acute encephalopathy are not clearly understood. Therefore, we assessed changes in brain function after suspected acute encephalopathy over time. METHODS We created a database of children admitted to the pediatric intensive care unit at Kobe Childrens Hospital because of convulsions or impaired consciousness with fever between 2002 and 2013. Clinical courses and outcomes were reviewed and patients who met the following criteria were included in the study: (1) 6months to 15years of age, (2) no neurological abnormality before onset, (3) treated for suspected acute encephalopathy, and (4) followed after 1 (0-2) month and 12 (10-17) months of onset. Outcomes were assessed using the Pediatric Cerebral Performance Category (PCPC) scale, with a score of 1 representing normal performance; 2, mild disability; 3, moderate disability; 4, severe disability; 5, vegetative state; and 6, brain death. RESULTS A total of 78 children (32 male) with a median (range) age at onset of 20 (6-172) months were enrolled. Fifty-one cases scored 1 on the PCPC, 13 scored 2, three scored 3, five scored 4, one scored 5, and five cases scored 6 at discharge. Whereas seven of the 13 cases that scored a 2 on the PCPC recovered normal brain function after 12months, none of the nine cases that scored a 3-5 on the PCPC recovered normal function. CONCLUSIONS Our findings suggest moderate to severe disability caused by acute encephalopathy had lasting consequences on brain function, whereas mild disability might result in improved function.

Two cases of traumatic head injury mimicking acute encephalopathy with biphasic seizures and late reduced diffusion

Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) presents a distinct clinical course of biphasic seizures and impaired consciousness. These symptoms are followed by reduced diffusion in the subcortical white matter on magnetic resonance imaging that is typically observed between 3 and 9 days after illness onset. Here, we report two cases of traumatic head injury with clinical and radiological features similar to those for AESD. The similarities between our cases and AESD may be useful in understanding the pathogenesis of AESD.

Current Situation of Treatment for Anaphylaxis in a Japanese Pediatric Emergency Center.

Objective Anaphylaxis is a systemic allergic reaction that sometimes requires prompt treatment with intramuscular adrenaline. The aim of the study was to investigate the current situation regarding anaphylaxis treatment in a representative pediatric primary emergency facility in Japan. Methods We retrospectively examined the medical records dating from April 2011 through March 2014 from Kobe Childrens Primary Emergency Medical Center, where general pediatricians work on a part-time basis. Clinical characteristics and current treatments for patients with anaphylaxis who presented to the facility were investigated. Furthermore, we compared the clinical characteristics between anaphylaxis patients given intramuscular adrenaline and those not given it. Results During the study period, 217 patients were diagnosed with anaphylaxis. The median Sampson grade at the time of visit was 2, and 90 patients (41%) were grade 4 or higher. No patients received self-intramuscular injected adrenaline before arrival at our emergency medical center because none of the patients had been prescribed it. Further treatment during the visit was provided to 128 patients (59%), with only 17 (8%) receiving intramuscular adrenaline. Patients given intramuscular adrenaline had significantly lower peripheral saturation of oxygen at the visit (P = 0.025) and more frequent transfer to a referral hospital (P < 0.001) than those not given intramuscular adrenaline. Conclusions Education for Japanese pediatric practitioners and patients is warranted, because no patients used self-intramuscular injected adrenaline as a prehospital treatment for anaphylaxis, and only severely affected patients who needed oxygen therapy or hospitalization received intramuscular adrenaline in a pediatric primary emergency setting.

Midazolam Fails to Prevent Neurological Damage in Children With Convulsive Refractory Febrile Status Epilepticus

BACKGROUND We conducted a retrospective study to compare the outcome of intravenous midazolam infusion without electroencephalography or targeted temperature management and barbiturate coma therapy with electroencephalography and targeted temperature management for treating convulsive refractory febrile status epilepticus. PATIENTS Of 49 consecutive convulsive refractory febrile status epilepticus patients admitted to the pediatric intensive care unit of our hospital, 29 were excluded because they received other treatments or because of various underlying illnesses. Thus, eight patients were treated with midazolam and 10 with barbiturate coma therapy using thiamylal. Midazolam-treated patients were intubated only when necessary, whereas barbiturate coma therapy patients were routinely intubated. Continuous electroencephalography monitoring was utilized only for the barbiturate coma group. The titration goal for anesthesia was clinical termination of status epilepticus in the midazolam group and suppression or burst-suppression patterns on electroencephalography in the barbiturate coma group. Normothermia was maintained using blankets and neuromuscular blockade in the barbiturate coma group and using antipyretics in the midazolam group. Prognoses were measured at 1 month after onset; children were classified into poor and good outcome groups. RESULTS Good outcome was achieved in all the barbiturate coma group patients and 50% of the midazolam group patients (P = 0.02, Fishers exact test). CONCLUSIONS Although the sample size was small and our study could not determine which protocol element is essential for the neurological outcome, the findings suggest that clinical seizure control using midazolam without continuous electroencephalography monitoring or targeted temperature management is insufficient in preventing neurological damage in children with convulsive refractory febrile status epilepticus.