Ayumi Endo

Posterior reversible encephalopathy syndrome in childhood: report of four cases and review of the literature.

Background Posterior reversible encephalopathy syndrome (PRES) is a recently described disorder with typical radiological findings of bilateral gray and white matter abnormalities in the posterior regions of the cerebral hemispheres and cerebellum. Its clinical symptoms include headache, decreased alertness, mental abnormalities such as confusion, diminished spontaneity of speech, and changed behavior ranging from drowsiness to stupor, seizures, vomiting, and abnormalities of visual perception such as cortical blindness. In this study, the clinical and radiological findings of 4 children with this syndrome due to a variety of conditions are reported. Methods The records of 4 children with a diagnosis of PRES were retrospectively analyzed. Results PRES is associated with a disorder of cerebrovascular autoregulation of multiple etiologies. Four patients with PRES who had primary diagnoses of severe aplastic anemia, nephritic syndrome, Henoch-Schönlein purpura, and acute poststreptococcal glomerulonephritis are presented. This syndrome has been described in numerous medical conditions, including hypertensive encephalopathy, eclampsia, and with the use of immunosuppressive drugs. Conclusions Early recognition of PRES as a complication during different diseases and therapies in childhood may facilitate precise diagnosis and appropriate treatment.

The relationship between drug treatment and the clinical characteristics of febrile seizures

BackgroundDrugs such as theophylline, antihistamines, and antiallergics with anti-histaminic actions have been shown to induce febrile seizures. The relationship between febrile seizures and medications has not been actively investigated. The present study aimed to investigate the relationship between the clinical characteristics of febrile seizures and the use of medications.MethodsTwo hundred and sixty-five children treated at our emergency room due to febrile seizures were studied to investigate the relationship between the clinical characteristics of febrile seizures, such as the type and duration of convulsions, and the drug treatment.ResultsThe duration of convulsions was longer among children who took theophylline and antihistamines than among children who did not take these medications. Of the antihistamines, mequitazine did not prolong the duration of convulsion.ConclusionsTheophylline should not be used in febrile children, particularly infants. Cautions should be taken in using histamine H1 antagonists in young infants because such drugs could potentially disturb the anticonvulsive central histaminergic system. However, mequitazine appears to be a suitable antihistamine for use in children with febrile seizures, since it does not prolong convulsions.

Acute encephalopathy with pandemic (H1N1) 2009 virus infection.

Objectives In April 2009, a novel influenza A (H1N1) pdm virus was identified in Mexico and spread quickly around the world. However, the clinical features of acute encephalopathy associated with 2009 pandemic influenza have not yet been elucidated. Methods We treated 8 patients (3 boys and 5 girls) aged 4 to 11 years (average age, 8 y 3 months) with influenza virus–associated encephalopathy, who presented at our 2 hospitals between July 2009 and March 2010. We investigated the clinical characteristics, treatments, and outcomes in the patients. Results In all patients, brain computed tomography showed mild to severe diffuse cerebral edema, and electroencephalography revealed diffuse high-voltage slow waves. They were all treated with oseltamivir and methylprednisolone pulse therapy. Six patients recovered without any sequelae; however, the remaining 2 had residual neurological sequelae. These 2 patients presented with severe disturbance of consciousness, and their central nervous system symptoms appeared within 12 hours after the onset of fever. One patient had periventricular leukomalacia and symptomatic epilepsy by perinatal brain hypoxia, and the other patient had 1 complex febrile and 2 febrile seizures. Conclusions This study showed that patients with influenza-associated encephalopathy caused by influenza A (H1N1) pdm infection were all older than those with seasonal influenza. Underlying neurological disease or history may be associated with poor prognosis.

A 3-year-old boy with Guillain–Barré syndrome and encephalitis associated with Mycoplasma pneumoniae infection

Mycoplasma pneumoniae is a common cause of respiratory tract illness in children. Among the most common extrapulmonary manifestations are disorders of the central nervous system, including meningitis, meningoencephalitis, cerebellitis, polyneuropathy, acute disseminated encephalomyelitis, and Guillain-Barré syndrome. Guillain-Barré syndrome, also known as acute inflammatory demyelinating polyradiculoneuropathy, is an acute-onset, immune-mediated disorder of the peripheral nervous system. The central nervous system is usually intact in patients with Guillain-Barré syndrome. However, there have been some reports of an association of Guillain-Barré syndrome with central nervous system involvement in children. We report a 3-year-old boy with M. pneumoniae infection associated with Guillain-Barré syndrome and encephalitis. Both serum anti-GM1 ganglioside (IgG and IgM) and anti-galactocerebroside IgG antibodies were detected in our patient: the former in the earlier stage of the disease, and the latter in the later stage. We speculate that anti-GM1 ganglioside was associated more with encephalitis, and anti-galactocerebroside antibody was associated more with GBS in our case. Our patient is the youngest report of Guillain-Barré syndrome with central nervous system involvement, and the first report of a pediatric patient with associated M. pneumoniae infection. Such cases are rarely reported, but highlight the need for awareness of the association of the infection with Guillain-Barré syndrome with central nervous system involvement.

Improvement of intractable childhood epilepsy following acute viral infection

In this study, we report 11 patients with intractable childhood epilepsy that improved following acute viral infection. The patients were 8 boys and 3 girls. Six of the 11 children were diagnosed as West syndrome (5 of the symptomatic type and 1 of the cryptogenic type). The remaining 5 children were myoclonic seizures. The patients became seizure free within 6 days following acute viral infections without an exchange or addition of antiepileptic drugs (AEDs). The types of acute viral infections were Exanthema subitum (Roseola infantum) in 5 patients, Rotavirus gastroenteritis in 2 patients, Measles infection in 2 patients, Herpetic stomatitis in 1 patient and Common cold in the remaining patient. Salaam seizures and/or tonic spasms disappeared within 6 days after the onset of viral infections, and hypsarrhythmia evolved to localized spikes on electroencephalography (EEG) in the patients with West syndrome. Epileptic seizures disappeared rapidly and EEG gradually normalized or improved in patients with myoclonic seizures. Four patients became seizure free for 5 years to 20 years. In 6 patients, seizures relapsed within 14 days to 1 month after the disappearance of seizures. One child remained seizure free for 12 months after viral infection. Common factors in 4 children who were continuously seizure free include (1) normal or almost normal findings of brain CT/MRI, (2) normal development prior to the onset of epileptic seizures, and (3) a short time interval between the onset of seizures and the acute viral infection. We propose several hypotheses including an immunological effect for the improvement of intractable childhood epilepsy following acute viral infection. Further study may provide important information concerning the mechanism of seizure control and the applicable to treatment for intractable childhood epilepsy.

Event-related potentials in response to 3-D auditory stimuli.

To evaluate auditory spatial cognitive function, age correlations for event-related potentials (ERPs) in response to auditory stimuli with a Doppler effect were studied in normal children. A sound with a Doppler effect is perceived as a moving audio image. A total of 99 normal subjects (age range, 4-21 years) were tested. In the task-relevant oddball paradigm, P300 and key-press reaction time were elicited using auditory stimuli (1000 Hz fixed and enlarged tones with a Doppler effect). From the age of 4 years, the P300 latency for the enlarged tone with a Doppler effect shortened more rapidly with age than did the P300 latency for tone-pips, and the latencies for the different conditions became similar towards the late teens. The P300 of auditory stimuli with a Doppler effect may be used to evaluate auditory spatial cognitive function in children.

Changes in Cerebral Blood Oxygenation Induced by Active Standing Test in Children with POTS and NMS

Orthostatic dysregulation (OD) has been classified into subtypes by heart rate and blood pressure; however, the hemodynamics of brains have not yet been revealed. Therefore, we investigated changes in cerebral blood flow and oxygenation during an active standing test to clarify the pathophysiology of two subtypes: postural tachycardia syndrome (POTS) and neurally mediated syncope (NMS). We studied 31 children (15 boys, 16 girls; mean age, 14.0 ± 1.7 years) who presented with OD at the Department of Pediatrics and Child Health, Nihon University School of Medicine between 2009 and 2011. OD was diagnosed using the Japanese clinical guidelines for juvenile orthostatic dysregulation. After a 10-min resting period in the supine position, patients were asked to quickly stand up and keep upright for 10 min. Cerebral blood flow and cerebral oxygenation were measured using transcranial Doppler sonography and near-infrared spectroscopy. POTS showed a significant decrease of oxy-Hb and resistance index (RI), suggesting transient ischemia with maintainable cerebral autoregulation. NMS showed a decrease of oxy-Hb and an increase of RI, suggesting ischemia and impairment of autoregulation.

Liver-specific mitochondrial respiratory chain complex I deficiency in fatal influenza encephalopathy

We report on a 4-year-old boy who died from influenza encephalopathy. The clinical course and microscopic findings of the autopsied liver were compatible with Reyes syndrome. We examined the mitochondrial respiratory chain function by blue native polyacrylamide gel electrophoresis (BN-PAGE), western blotting, and respiratory chain enzyme activity assays. The activity of liver respiratory chain complex (CO) I was markedly decreased (7.2% of the respective control activity); whereas, the other respiratory chain complex activities were substantially normal (CO II, 57.9%; CO III, 122.3%; CO IV, 161.0%). The activities of CO I-IV in fibroblasts were normal (CO I, 82.0%; CO II, 83.1%; CO III, 72.9%; CO IV, 97.3%). The patient was diagnosed with liver-specific complex I deficiency. This inborn disorder may have contributed to the fatal outcome. We propose that relying only on fibroblast respiratory chain complex activities may lead to the misdiagnosis of liver-specific complex I deficiency.