A patient with compound heterozygosity of SMPD4: Another example of utility of exome-based copy number analysis in autosomal recessive disorders.

For the efficient diagnosis of rare and undiagnosed diseases, the parallel detection of copy number variants (CNVs) and single nucleotide variants using exome analysis is required. Recently, our group reported the usefulness of a program called EXCAVATOR2, which screens for CNVs from aligned exome data in bam format. This method is expected to contribute to the identification of structural variants and to improve the diagnosis rate, especially for the diagnosis of autosomal recessive disease, when a conventional exome analysis identifies a pathogenic variant in one allele but not the other. Here we report a 2-year-old Japanese boy with an undiagnosed disease. He had severe neonatal asphyxia, severe intellectual disability, intractable seizures, cerebellar and brainstem hypoplasia and dysmorphic features including a prominent supraorbital ridge, thin upper lip, and prominent antihelix. An exome analysis reinforced with a copy number analysis using the EXCAVATOR2 method revealed that the patient had a hemizygous variant in chr2(GRCh37):g.130925108G>A, NM_017951.4 c.832C>T, p.(Arg278*) in SMPD4 that was derived from his father and a deletion of SMPD4 derived from his mother. The presence of the deletion spanning SMPD4 was confirmed by short-read and long-read whole-genome sequencing. The successful diagnosis of this reported patient demonstrates the diagnostic utility of EXCAVATOR2 and overcomes the weakness of exome analysis for the detection of autosomal recessive diseases in nonconsanguineous families, significantly impacting genetic counseling for family planning.

Unsatisfactory Short-Term Neurodevelopmental Outcomes of Preterm Infants Who Received Polymyxin B-Immobilized Fiber Column-Direct Hemoperfusion for Septic Shock.

Sepsis and septic shock are associated with high mortality and neurodevelopmental impairment in preterm infants. Recently, endotoxin and mediator removal using a polymyxin B-immobilized fiber column for direct hemoperfusion (PMX-DHP) has been used for the management of septic shock even in neonates. Although early withdrawal from shock with PMX-DHP contributes to survival, its effect on neurodevelopment after discharge is unclear. This study aimed to examine short-term neurodevelopmental impairment in preterm infants with septic shock who were treated with PMX-DHP. We retrospectively assessed five infants who received treatment with PMX-DHP (median 25.5 [interquartile range: 24.8-28.3] weeks and 817 [interquartile range: 667-954] g). Neurodevelopmental outcomes were assessed with the Kyoto Scale of Psychological Development 2001 at a median 34.5 (interquartile range: 29.5-44.5) months of corrected age after discharge. The short-term neurodevelopmental prognosis of preterm infants treated with PMX-DHP for septic shock was delayed (overall developmental quotient < 70) with an average quotient of 57.3. Furthermore, four (80%) of five patients presented with intraventricular hemorrhage and another four (80%) with periventricular leukomalacia. In conclusion, preterm infants with septic shock treated with PMX-DHP had unsatisfactory short-term neurodevelopmental outcomes. Hence, the effect of PMX-DHP in improving neurodevelopmental prognosis even in preterm infants with septic shock should be further evaluated.

A nationwide survey of adenovirus-associated encephalitis/encephalopathy in Japan.

BACKGROUND: Adenovirus is a major pathogen causing febrile illness among children. It may also cause acute encephalitis/encephalopathy. This study aimed to elucidate the clinical features of adenovirus-associated encephalitis/encephalopathy (AdVE) among children in Japan. METHODS: A nationwide survey of children with AdVE was conducted. An initial survey was distributed among pediatricians to obtain information about children with AdVE treated between January 2014 and March 2019. A second survey was used to obtain the clinical information of children with AdVE from hospitals that responded to the initial survey and those identified from a literature search of the reported cases. We collected demographic data and information about symptoms of infection, neurological symptoms, laboratory parameters, treatment, and outcomes. Outcomes were determined using the Pediatric Cerebral Performance Category Score. RESULTS: Clinical information was available for 23 children with a median age of 39 months. Two had preexisting neurological disorders and six had a history of febrile seizures. The outcome was good in 15 patients and poor in eight patients. Serum lactate dehydrogenase, glucose, and ammonia levels were higher among children with a poor outcome compared to those with a good outcome. Clinically mild encephalitis/encephalopathy with a reversible splenial lesion was the most common type (n = 8), followed by acute encephalopathy with biphasic seizures and late reduced diffusion (n = 7). CONCLUSION: A prior history of febrile seizures was frequent in children with AdVE. Several different subtypes of acute encephalopathy were seen in children with AdVE, and the outcome was poor in those with acute encephalopathy with biphasic seizures and late reduced diffusion and hemorrhagic shock and encephalopathy syndrome. Elevated lactate dehydrogenase, glucose, and ammonia levels on admission were found to correlate with a poor outcome.

Lateralized interictal epileptiform discharges during rapid eye movement sleep correlate with epileptogenic hemisphere in children with intractable epilepsy secondary to tuberous sclerosis complex.

PURPOSE: We assessed lateralization of interictal epileptiform discharges (IEDs) in children with intractable epilepsy secondary to tuberous sclerosis complexes (TSCs) during rapid eye movement sleep (R), compared with non-rapid eye movement sleep (NR) and wakefulness (W), to determine epileptogenicity of R-IEDs. METHODS: We retrospectively studied 23 children with TSC, who underwent prolonged scalp video-electroencephalography (EEG) and magnetic resonance imaging (MRI). We determined the lateralization of ictal EEG, clinical semiology, and the largest tuber on MRI. We analyzed a minimum of 100 IEDs during R, NR, and W to classify right/left/generalized spikes to compare the lateralization with ictal EEG, clinical semiology, and MRI. KEY FINDINGS: R-IEDs were lateralized in 22 patients (96%), W-IEDs in 19 (83%), and NR-IEDs in 16 (70%). Ictal EEGs were lateralized in 15 patients (65%) and clinical semiology in 5 (22%). Ictal EEG lateralization was concordant to R-IEDs in 14 patients (93%), W-IEDs in 11 (73%), and NR-IEDs in 10 (67%). The lateralization of clinical semiology was concordant with R-IEDs in 4 (80%), W-IEDs in 3 (60%), and NR-IEDs in 2 (40%). MRI lateralization of the largest tuber was concordant with R-IEDs in 16 (70%), W-IEDs in 12 (52%), and NR-IEDs in 11 (48%). Thirteen patients (57%) underwent resective surgery, the hemisphere of which was concordant with R-IEDs in 13 (100%), W-IEDs in 8 (62%), and NR-IEDs in 8 (62%). Nine (69%) of them achieved good seizure control after surgery. SIGNIFICANCE: R provoked the most lateralized IEDs compared to NR and W in children with TSC. Lateralization of R-IEDs corresponded with the hemisphere of ictal EEG and largest tuber, and can be used to identify surgical candidacy in TSC children with intractable epilepsy.

A nationwide survey of norovirus-associated encephalitis/encephalopathy in Japan.

BACKGROUND: Norovirus is a major pathogen of gastroenteritis and is known to cause encephalitis/encephalopathy. The aim of this national survey was to clarify the clinical features of norovirus-associated encephalitis/encephalopathy (NoVE) among children in Japan. METHODS: A nationwide survey of children with NoVE was conducted using a structured research form. The initial survey asked pediatricians about children with NoVE treated between January 2011 and March 2016. The second survey obtained patient information from two sources: hospitals that responded to the initial survey and those identified as having treated cases from a literature search. RESULTS: Clinical information was available for 29 children. Their median age was 2 y 8 m. The outcome was good in 13 patients and poor in 15. The interval between the onset of gastrointestinal symptoms and that of encephalitis/encephalopathy was significantly shorter in those with a poor outcome. At the onset of an elevated serum creatinine level and an abnormal blood glucose level were correlated with a poor outcome. Regarding the subtypes of encephalitis/encephalopathy, acute encephalopathy with biphasic seizures and late reduced diffusion and hemorrhagic shock and encephalopathy syndrome were frequent. CONCLUSION: The outcome of children with NoVE was poor. Early onset of neurological symptoms, an elevated serum creatinine level, and an abnormal blood glucose level were associated with a poor outcome. No effective treatment was identified and this should be the subject of future studies.

Efficacy and safety of fosphenytoin for acute encephalopathy in children.

PURPOSE: To evaluate the efficacy and safety of fosphenytoin (fPHT) for the treatment of seizures in children with acute encephalopathy. METHODS: Using responses from physicians on the Annual Zao Conference on Pediatric Neurology mailing list we chose patients who met the following criteria: clinical diagnosis of acute encephalopathy and use of intravenous fPHT for the treatment of seizures. We divided the patients into two groups: acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) and other encephalopathies. The efficacy of fPHT was considered effective when a cessation of seizures was achieved. RESULTS: Data of 38 children were obtained (median age, 27 months). Eighteen children were categorized into the AESD group and 20 into the other encephalopathies group. fPHT was administered in 48 clinical events. The median loading dose of fPHT was 22.5 mg/kg and was effective in 34 of 48 (71%) events. The rate of events in which fPHT was effective did not differ according to the presence or absence of prior antiepileptic treatment, subtype of acute encephalopathy, or the type of seizures. One patient experienced apnea and oral dyskinesia as adverse effects of fPHT, whereas arrhythmia, hypotension, obvious reduction of consciousness, local irritation, phlebitis and purple grove syndrome were not observed in any patient. CONCLUSION: fPHT is effective and well tolerated among children with acute encephalopathy.