Outcome of acute necrotizing encephalopathy in relation to treatment with corticosteroids and gammaglobulin

Gastric perforation and critical illness polyneuropathy after steroid treatment in a patient with encephalitis/encephalopathy with transient splenial lesion

The outcome of mild encephalitis/encephalopathy with reversible splenial lesion (MERS) is favorable whether or not specific treatment is performed. We report a patient with MERS treated with methylprednisolone, complicated by gastric perforation followed by critical illness polyneuropathy. The patient was a 14-year-old male with mildly impaired consciousness and hyponatremia who was treated with methylprednisolone pulse therapy. High fever appeared after methylprednisolone pulse therapy and free air was recognized on an abdomen roentgenogram. Gastric perforation was recognized on emergent endoscopic surgery and omental implantation repair was performed. His consciousness was fully recovered after surgery, whereas he was noted to have motor and sensory impairment of the lower extremities and vesico-rectal disturbance. Nerve conduction studies revealed decreased compound muscle action potentials with preserved motor conduction velocity and decreased sensory nerve action potentials. He was diagnosed as having critical illness polyneuropathy, and bedside physical rehabilitation was initiated. His neurological symptoms resolved within 6months. Our patient highlighted possible serious adverse events associated with steroid treatment for children with MERS.

Neuroimaging of Infectious and Inflammatory Diseases of the Pediatric Cerebellum and Brainstem

Cerebellar involvement by infectious-inflammatory conditions is rare in children. Most patients present with acute ataxia, and are typically previously healthy, young (often preschool) children. Viral involvement is the most common cause and ranges from acute postinfectious ataxia to acute cerebellitis MR imaging plays a crucial role in the evaluation of patients suspected of harboring inflammatory-infectious involvement of the cerebellum and brainstem. Knowledge of the imaging features of these disorders and technical competence on pediatric MR imaging are necessary for a correct interpretation of findings, which in turn prompts further management.

Acute Necrotizing Encephalopathy of Childhood Secondary to Dengue Infection: A Case Report from Pakistan

Acute necrotizing encephalopathy of childhood (ANEC) is a rare condition mainly affecting children with a distinct clinico-radiologic pattern. Initially thought to be secondary to respiratory viral infections, there have been more insights to the pathogenesis of ANEC including genetics. We present a case of a girl who developed this condition with classical clinico-radiologic findings of ANEC secondary to severe dengue infection and could not survive. We report this case with the aim to raise awareness about this fatal complication of dengue infection as dengue has become a global health-care problem.

RANBP2 mutation in an Indian child with recurrent acute necrotizing encephalopathy

BACKGROUND

Acute necrotizing encephalopathy (ANE) is a rare disorder characterized by encephalopathy following a febrile illness, mostly viral. Most cases are sporadic; however, recurrent and familial cases have been linked to RANBP2 mutation.

DESCRIPTION OF THE CASE

This is a description of a three and half years old girl with recurrent ANE with RANBP2 mutation (c.1754 C>T (p.T585M)). She had two episodes of encephalopathy, each following a short non-specific febrile illness. Neuroradiologically, she had typical findings involving bilateral thalami during the first episode and involving bilateral temporal and occipital lobes, bilateral cerebellar hemispheres and brainstem during the second episode. She was managed with intravenous gamma globulin and dexamethasone during both the episodes. She recovered significantly with residual deficits in her cognitive and language domains.

CONCLUSIONS

In relevant clinic-radiological scenarios both isolated and recurrent ANE should be considered because of treatment and long-term outcome related implications.

Serial outcomes in acute necrotising encephalopathy of childhood: A medium and long term study

OBJECTIVE

Acute necrotising encephalopathy (ANEC) is a severe, debilitating childhood disorder. We used the ANEC scoring system (ANE-ss) and standardised neurodevelopmental scores to objectively characterise medium and long term outcomes.

METHODS

Retrospective review of children with ANEC at KK Women's and Children's Hospital, Singapore, from 2005 to 2012. ANE-ss was determined from clinical features and neuroimaging, and neurodevelopmental scores (Pediatric Glasgow Outcome Scale Extended, Pediatric Cerebral Performance Category scale and Pediatric Overall Performance Category scale) were applied at 1, 6, 12 and 24months post diagnosis.

RESULTS

Seven patients with ANEC were studied. All had a viral prodrome with fever, and encephalopathy at presentation, and received immunotherapy (steroids or immunoglobulin). ANE-ss scores were medium risk in 4 patients and high risk in 3 patients. One died (high risk ANE-ss) and outcome was determined in the 6 survivors. At 1month post diagnosis, 3 patients (50%) were mildly affected and 3 (50%) were severely affected. Morbidity rates improved by 12months, with 67% and 33.3% scoring in the mildly affected and severely affected ranges, respectively. Medium risk patients did well with majority having little or no neurological deficits and good outcome scores.

CONCLUSION

Mortality and severe morbidity correlated well with high risk ANE-ss. However, our patients with medium risk ANE-ss had good neurodevelopmental sequelae. Serial disability scoring is useful in evaluating the progress of ANEC patients on follow up. Assessment at 1month post diagnosis can aid prognostication of long term outcome.

Familial acute necrotizing encephalopathy without RANBP2 mutation: Poor outcome

Most childhood cases of acute necrotizing encephalopathy (ANE) involve neither family history nor recurrence. ANE occasionally occurs, however, as a familial disorder or recurs in Caucasian patients. A mutation of RAN-binding protein 2 (RANBP2) has been discovered in more than one half of familial or recurrent ANE patients. In contrast, there has been no report of this mutation in East Asia. Here, we report the first sibling cases of typical ANE in Japan, with poor outcome. DNA analysis of genes associated with ANE or other encephalopathies, including RANBP2 and carnitine palmitoyl transferase II (CPT2), indicated neither mutations nor disease-related polymorphisms. On literature review, recurrent or familial ANE without the RANBP2 mutation has a more severe outcome and greater predilection for male sex than that with the RANBP2 mutation. This suggests that there are unknown gene mutations linked to ANE.

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 Children's 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.

Acute Postviral Encephalopathy: Pathologic and Radiologic Correlation in an Atypical Case

The authors report a case of fatal acute encephalopathy following influenza infection, with slightly atypical pathological and imaging findings. A healthy 8-year-old boy with probable recent influenza A/B infection admitted for refractory seizures was placed on phenobarbital coma and later developed hemodynamic instability. Magnetic resonance imaging revealed bilateral cerebral and cerebellar white matter lesions and microhemorrhages. Following his demise, the autopsy revealed a large area of necrosis in the right centrum semiovale with similar lesions in the temporal and cerebellar regions. Microscopically, there was extensive coagulative necrosis, compatible with necrotizing white matter encephalopathy, and neuronal loss suggesting superimposed hypoxic–ischemia. The acute progressive neurologic deterioration was partly reminiscent on acute necrotizing encephalopathy, a condition recently associated with influenza A. In acute necrotizing encephalopathy, typical brain findings are characterized by bilateral thalamic necrosis/petechiae with variable white matter edema. The somewhat atypical findings in our case can relate to superadded cardiovascular collapse and hypoxic–ischemic effects.

Targeted temperature management for acute encephalopathy in a Japanese secondary emergency medical care hospital

BACKGROUND

The goals of this study, conducted in our secondary emergency care hospital, were to assess the effectiveness of targeted temperature management (TTM) for acute encephalopathy secondary to status epilepticus and to consider appropriate adaptations for use of TTM in this setting.

METHODS

Medical records of patients admitted with acute encephalopathy to Hirakata City Hospital between January 2010 and December 2014 were retrospectively reviewed. Cases treated with TTM (36 °C) and methylprednisolone pulse (MP) therapy (TTM/MP) were compared with those treated with conventional MP regarding clinical courses and outcomes.

RESULTS

In total, 20 children were retrospectively enrolled. In the TTM/MP group (10 cases) all survived intact. In the MP group (10 cases), 4 cases were left with neurological sequelae. Furthermore, in the TTM/MP group, the body temperature dropped more quickly. For pediatricians in this secondary emergency hospital, implementing the body temperature management system was not difficult. There were no complications caused by hypothermia.

DISCUSSION

Use of TTM as the initial treatment for acute encephalopathy in the early-onset stage is possible in a secondary emergency care hospital. However, some acute encephalopathy cases are the so-called fulminant type; DIC or shock develops soon after onset and so it is sometimes difficult to introduce TTM. Fulminant-type patients should be transported to tertiary emergency care hospitals. Secondary emergency care hospitals must carefully select cases for TTM, keeping the possibility of transport to a tertiary emergency hospital in mind at all times.

Acute necrotizing encephalopathy in an adult

Acute necrotizing encephalopathy (ANE) is a rapidly progressing neurologic disorder that occurs in children after common viral infections of the respiratory or gastrointestinal systems. This disease is commonly seen in East Asia. Normal healthy infants and children can get affected. The condition carries a poor prognosis with high morbidity and mortality rates. We report here a case of a 23-year-old female with ANE and describe its neuroimaging findings. Magnetic resonance imaging examination performed showed symmetric lesions involving the thalami, brainstem, and cerebellum.

Serum tau protein as a marker of disease activity in enterohemorrhagic Escherichia coli O111-induced hemolytic uremic syndrome

Tau protein levels in cerebrospinal fluid (CSF) and serum are elevated in patients with various central nervous system diseases. We investigated whether serum tau protein levels are useful for predicting and assessing disease activity of acute encephalopathy (AE) in enterohemorrhagic Escherichia coli (EHEC) O111-induced hemolytic uremic syndrome (HUS; EHEC encephalopathy). Serum samples were obtained from 14 patients with EHEC O111/HUS, 20 patients with non-EHEC-related AE, and 20 age- and sex-matched healthy controls. CSF samples were obtained from 2 patients with EHEC encephalopathy and 20 patients with non-EHEC-related AE. Tau protein levels and levels of several proinflammatory cytokines were quantified by enzyme-linked immunosorbent assays. Results were compared with the clinical features of EHEC encephalopathy, including magnetic resonance image (MRI) findings. Serum tau levels in patients with EHEC encephalopathy were significantly elevated compared with those in patients with EHEC O111/HUS without encephalopathy, patients with non-EHEC-related AE, and healthy controls. The ratio of CSF tau levels to serum tau levels was >1.0 in all patients with non-EHEC-related AE but <1.0 in 2 patients with EHEC encephalopathy. Serum tau protein levels increased rapidly and markedly in patients with severe EHEC 0111/HUS and encephalopathy when HUS occurred, but were not elevated in mild patients, even in the HUS phase. Furthermore, changes in serum tau protein levels in patients with EHEC encephalopathy were consistent with abnormalities on brain MRI and were positively correlated with proinflammatory cytokine levels. Our results indicate that serum tau protein might be useful to predict and assess disease activity of EHEC encephalopathy.

Acute necrotizing encephalopathy: an underrecognized clinicoradiologic disorder

Acute necrotizing encephalopathy (ANE) is a rare but distinctive type of acute encephalopathy with global distribution. Occurrence of ANE is usually preceded by a virus-associated febrile illness and ensued by rapid deterioration. However, the causal relationship between viral infections and ANE and the exact pathogenesis of ANE remain unclear; both environmental and host factors might be involved. Most cases of ANE are sporadic and nonrecurrent, namely, isolated or sporadic ANE; however, few cases are recurrent and with familial episodes. The recurrent and familial forms of ANE were found to be incompletely autosomal-dominant. Further the missense mutations in the gene encoding the nuclear pore protein Ran Binding Protein 2 (RANBP2) were identified. Although the clinical course and the prognosis of ANE are diverse, the hallmark of neuroradiologic manifestation of ANE is multifocal symmetric brain lesions which are demonstrated by computed tomography (CT) or magnetic resonance imaging (MRI). The treatment of ANE is still under investigation. We summarize the up-to-date knowledge on ANE, with emphasis on prompt diagnosis and better treatment of this rare but fatal disease.

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 Children's 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.

A severity score for acute necrotizing encephalopathy

OBJECTIVE

To develop a score that predicts the prognosis of children with acute necrotizing encephalopathy (ANE).

METHOD

We retrospectively evaluated clinical variables and neurological outcome in two cohorts of children with ANE. Firstly, we developed the ANE severity score (ANE-SS) according to the clinical variables that correlated with neurological outcome in 41 children who were included in our previous reports in 2009. We then applied the scoring system to a second cohort of 32 patients who were newly collected in 2011. We investigated the correlation between the ANE-SS and neurological outcome in all 73 patients.

RESULTS

In the first cohort, brain stem lesions on MRI and state of shock at onset were significantly correlated with outcome. Age over 48 months, elevated CSF protein, and low platelet counts tended to be correlated with outcome. No types of treatment were correlated with outcome. The developed ANE-SS ranged from 0 to 9 points, with 3 points for existence of shock, 2 points for brain stem lesions, 2 points for age over 48 months, 1 point for platelet count below 100,000/μL, and 1 point for CSF protein above 60 mg/dl. Patients were classed as low risk (ANE-SS 0-1 points), medium risk (ANE-SS 2-4 points), or high risk (ANE-SS 5-9 points). ANE-SS was significantly correlated with outcome in the group of 73 patients.

CONCLUSION

ANE-SS can be used to predict outcome in patients with ANE. More effective treatments need to be developed for high-risk patients.

RANBP2 mutation and acute necrotizing encephalopathy: 2 cases and a literature review of the expanding clinico-radiological phenotype

BACKGROUND

Acute necrotising encephalopathy (ANE) is a rapidly progressive encephalopathy associated with acute viral illness. A missense mutation in nuclear pore gene RANBP2 has been identified as a major cause of familial and recurrent ANE, which is now termed as ANE1. First presentation of ANE can mimic an acute disseminated encephalomyelitis (ADEM), although ANE presents in a slightly younger age group. Identification of this disorder at radiological study is the most important determinant of the outcome. ANE1 is inherited as autosomal dominant, but shows incomplete penetrance.

METHODS

We report two female children who presented with atypical clinical presentation (afebrile) and atypical radiological presentation (lack of bilateral thalamic involvement), not fitting into the original diagnostic criteria for ANE1. Both received steroid therapy for a presumed diagnosis of ADEM and made good clinical recovery. We also reviewed the available literature on ANE1, including the clinical profile, MRI brain descriptions, CSF characteristics and common mutations.

RESULTS

A total of 59 patients are reported in patients with ANE1 were identified, the incidence of ANE was higher in younger age group (<4 yrs) as compared to ADEM 5.3 yrs (3.6-7). Male and female were equally affected. High CSF protein (>0.45 g/l) was reported in 44/47 (94%) in absence CSF pleocytosis (Cells > 5 × 10(6)/L). Neuroimaging findings showed multifocal involvement across different studies, and bilateral thalamic involvement was seen in 77% of patients.

CONCLUSION

Based on the literature review of ANE1 with RANBP2 mutation, we propose a threshold for RANBP2 mutation testing.

Only a Touch of the Flu? The Simultaneous Manifestation of Acute Necrotizing Encephalopathy in Two Consanguineous Patients

This case report describes the simultaneous manifestation of acute necrotizing encephalopathy in 2 consanguineous patients after infection with influenza B based on the autosomal dominant missense mutation of the RANBP2-gene. Differential diagnosis of acute encephalopathy, clinical and radiological clues, and treatment strategies are outlined.

Neurologic manifestations and complications of pandemic influenza A H1N1 in Malaysian children: what have we learnt from the ordeal?

INTRODUCTION

In 2009, pandemic influenza A H1N1 emerged in Mexico and subsequently spread worldwide. In Malaysia, there were more than a thousand of confirmed cases among children. The general clinical characteristics of these children have been well-published. However, the description of neurologic complications is scarce.

OBJECTIVE

This study aims to describe the characteristics of neurologic manifestations and complications in a national paediatric cohort with pandemic influenza A H1N1.

METHODS

During the pandemic, children (12 years or less) admitted for novel influenza A H1N1 in 68 Malaysian public hospitals, were prospectively enrolled into national database. The clinical, laboratory and neuro-imaging data for children with neurologic manifestations, hospitalized from 15th June 2009 till 30th November 2009, was reviewed.

RESULTS

Of 1244 children with influenza A H1N1 during the study period, 103 (8.3%) presented with influenza-related neurological manifestations. The mean age of our study cohort was 4.2 years (SD: 3.3 years). Sixty percent of them were males. Sixty-nine (66.9%) were diagnosed as febrile seizures, 16 (15.5%) as breakthrough seizures with underlying epilepsy, 14 (13.6%) as influenza-associated encephalopathy or encephalitis (IAE) and 4 (3.9%) as acute necrotizing encephalopathy of childhood (ANEC). All 4 available CSF specimens were negative for influenza viral PCR. Among 14 children with brain-imaging done, 9 were abnormal (2: cerebral oedema, 4: ANEC and 3: other findings). There were four deaths and three cases with permanent neurological sequelae.

CONCLUSION

About one-tenth of children with pandemic influenza A H1N1 presented with neurologic complications. The most common diagnosis was febrile seizures. One-fifth of those children with neurologic presentation had IAE or ANEC, which carried higher mortality and morbidity. This large national study provides us useful data to better manage children with neurologic complications in the future pandemic influenza outbreaks.

Familial acute necrotizing encephalopathy due to mutation in the RANBP2 gene

BACKGROUND

Acute necrotizing encephalopathy (ANE) is a rare and severe parainfectious central nervous system disease in which previously healthy children develop rapidly progressive coma following viral illness. While most ANE are sporadic, familial autosomal dominant ANE due to mutations in the RANBP2 gene has been recently reported (ANE1 or infection-induced acute encephalopathy-3 (IIAE3)). To date, only few IIAE3 families with ADANE episodes have been described.

OBJECTIVE

To report a new family with ADANE, describe clinical and radiological features and discuss differential diagnosis including Leigh syndrome or multiple sclerosis.

OBSERVATION

The family included 3 symptomatic individuals and one 59 year-old asymptomatic obligate carrier. Patients presented acute episodes of encephalopathy few days after common viral infection. Ages of onset ranged from 6 months to 5 years. Episodes not only occurred in childhood but also recurred in adulthood. Initial neurological signs included coma, focal neurological deficits and seizures. MRI showed typical necrotizing lesions primarily in the thalamus and brainstem, and in the temporal lobes and insula. CSF cell count and cultures were normal during episodes. RANBP2 gene screening identified pathogenic heterozygous c.1754C>T mutation (p.Thr585Met). Episodes led to cognitive or physical handicap in 2 patients and were fatal in one child.

CONCLUSION

IIAE3 or ADANE due to RANBP2 mutations has a large clinical heterogeneity. Our family illustrates the associated phenotypes from asymptomatic carrier to severe episodes of encephalopathy. Based on MRI features, the genetic IIAE3 diagnosis is important since prophylaxis and symptomatic management of infections may be beneficial, possibly in association with steroid or gammaglobulins.

Clinical outcome of acute necrotizing encephalopathy in related to involving the brain stem of single institution in Korea

Purpose

Acute necrotizing encephalopathy (ANE) is a fulminant disease of the brain characterized by bilateral thalamic lesions, and is prevalent among children in East Asia. The prognosis of ANE is usually poor with a high mortality rate and neurological sequelae. This study aimed to delineate the clinical characteristics and prognostic factors of ANE.

Methods

We retrospectively analyzed clinical data of 399 pediatric patients with encephalitis who were admitted to Samsung Medical Center from December 1998 to March 2011. We enrolled ten patients (11 cases) with ANE and analyzed their demographic, clinical, and neuroimaging data. The location and extent of the brain regions were checked based on fluid-attenuated inversion recovery, T1-, and T2-weighted imaging findings; the presence of contrast enhancement, restricted diffusion, and hemorrhage.

Results

Ten patients were identified, including one patient with two episodes. The median age of onset was 1.5 years (0.4-8.4 years). The mortality rate was 40%, and only 30% of patients survived without neurological sequelae. The definite involvement of the brainstem on brain magnetic resonance imaging was significantly correlated with mortality (P=0.04).

Conclusion

Broad and extensive brainstem involvement suggested the fulminant course of ANE. Early diagnosis of ANE before brainstem involvement, through careful identification of symptoms of brain dysfunction, may be the best way to achieve better neurological outcomes.

Neurological manifestations of influenza infection in children and adults: results of a National British Surveillance Study

BACKGROUND

The emergence of influenza A(H1N1) 2009 was met with increased reports of associated neurological manifestations. We aimed to describe neurological manifestations of influenza in adults and children in the United Kingdom that presented at this time.

METHODS

A 2-year surveillance study was undertaken through the British adult and pediatric neurological surveillance units from February 2011. Patients were included if they met clinical case definitions within 1 month of proven influenza infection.

RESULTS

Twenty-five cases were identified: 21 (84%) in children and 4 (16%) in adults. Six (29%) children had preexisting neurological disorders. Polymerase chain reaction of respiratory secretions identified influenza A in 21 (81%; 20 of which [95%] were H1N1) and influenza B in 4 (15%). Twelve children had encephalopathy (1 with movement disorder), 8 had encephalitis, and 1 had meningoencephalitis. Two adults had encephalopathy with movement disorder, 1 had encephalitis, and 1 had Guillain-Barré syndrome. Seven individuals (6 children) had specific acute encephalopathy syndromes (4 acute necrotizing encephalopathy, 1 acute infantile encephalopathy predominantly affecting the frontal lobes, 1 hemorrhagic shock and encephalopathy, 1 acute hemorrhagic leukoencephalopathy). Twenty (80%) required intensive care, 17 (68%) had poor outcome, and 4 (16%) died.

CONCLUSIONS

This surveillance study described a cohort of adults and children with neurological manifestations of influenza. The majority were due to H1N1. More children than adults were identified; many children had specific encephalopathy syndromes with poor outcomes. None had been vaccinated, although 8 (32%) had indications for this. A modified classification system is proposed based on our data and the increasing spectrum of recognized acute encephalopathy syndromes.

[Postinfectious family case of acute necrotizing encephalopathy caused by RANBP2 gene mutation]

Acute necrotizing encephalopathy is a rare neurologic disease most often triggered by a febrile viral event affecting an otherwise healthy infant. The clinical course is characterized by rapid deterioration of the neurological condition that often leads to coma and requires intensive care. The diagnosis is usually suggested by MRI, which shows symmetrical and focal necrotic lesions of thalami. Acute necrotizing encephalopathy has been linked in recent studies to an autosomal-dominant mutation of the gene for the protein RAN-binding protein 2.

CASE REPORT

We report three cases in siblings of Tunisian origin. Two of them presented with acute necrotizing encephalopathy at the age of 9 months in the immediate aftermath of a viral infection. The molecular study conducted in the family showed that both patients and their mother were carriers of the missense mutation gene RAN-binding protein 2.

COMMENTS

Although the role of Ran BP2 protein is incompletely known, mutation of the RANBP2 gene causes rare, reversible central neurologic disorders. Suspected diagnosis is facilitated by MRI, which shows specific lesions of multifocal, symmetric involvement of the thalami, brainstem tegmentum, supratentorial white matter, and cerebellum. Due to the low frequency of the disease and its non-specific clinical presentation, the diagnosis of acute necrotizing encephalopathy is a major challenge, while preventative measures can be proposed in familial mutation.

MRI gadolinium enhancement precedes neuroradiological findings in acute necrotizing encephalopathy

We report a 2-year-old Japanese boy with acute necrotizing encephalopathy (ANE) triggered by human herpes virus-6, who presented insightful magnetic resonance imaging (MRI) findings. He was admitted due to impaired consciousness and a convulsion, 2 days after the onset of an upper respiratory infection. At admission, cranial MRI showed marked gadolinium enhancement at the bilateral thalami, brainstem and periventricular white matter without abnormal findings in noncontrast MRI sequences. On the following day, noncontrast computed tomography demonstrated homogeneous low-density lesions in the bilateral thalami and severe diffuse brain edema. The patient progressively deteriorated and died on the 18th day of admission. The pathogenesis of ANE remains mostly unknown, but it has been suggested that hypercytokinemia may play a major role. Overproduced cytokines cause vascular endothelial damage and alter the permeability of the vessel wall in the multiple organs, including the brain. The MRI findings in our case demonstrate that blood-brain barrier permeability was altered prior to the appearance of typical neuroradiological findings. This suggests that alteration of blood-brain barrier permeability is the first step in the development of the brain lesions in ANE, and supports the proposed mechanism whereby hypercytokinemia causes necrotic brain lesions. This is the first report demonstrating MRI gadolinium enhancement antecedent to typical neuroradiological findings in ANE.

Acute necrotizing encephalopathy associated with enterovirus infection

Acute necrotizing encephalopathy is a rare, clinically distinct entity of acute encephalopathy triggered by acute febrile diseases, mostly viral infections. It is postulated to arise from uncontrolled cytokine release during a febrile illness, and is most often seen in East Asia. We describe a rare Saudi patient of acute necrotizing encephalopathy attributable to enterovirus in a 4 years and 6 months old girl. A work-up revealed elevations in serum and cerebrospinal fluid interleukin-6 and tumor necrosis factor-α. The outcome on intravenous pulse methylprednisolone was good. This case is the first, to the best of our knowledge, of acute necrotizing encephalopathy reported from Saudi Arabia with a good outcome despite severe magnetic resonance imaging findings and delay in the steroid treatment.

Novel Influenza A (H1N1)-Associated Acute Necrotizing Encephalopathy: A Case Report

Several cases of acute necrotizing encephalopathy (ANE) with influenza A (H1N1) have been reported to date. The prognosis of ANE associated with H1N1 is variable; some cases resulted in severe neurologic complication, whereas other cases were fatal. Reports mostly focused on the diagnosis of ANE with H1N1 infection, rather than functional recovery. We report a case of ANE with H1N1 infection in a 4-year-old Korean girl who rapidly developed fever, seizure, and altered mentality, as well as had neurologic sequelae of ataxia, intentional tremor, strabismus, and dysarthria. Brain magnetic resonance imaging showed lesions in the bilateral thalami, pons, and left basal ganglia. To our knowledge, this is the first report of ANE caused by H1N1 infection and its long-term functional recovery in Korea.

Influenza-associated neurological complications

While mostly diagnosed in the pediatric population, neurological complications of pandemic influenza A infection may affect young and previously healthy adults, and may follow a fulminant, severe, and occasionally fatal course. We reviewed severe neurological complications secondary to influenza infection reported in the literature, in attempt to outline recurrent syndromes that may assist the clinician in making a timely diagnosis. Vigilance and awareness of these clinical entities are key in the neurologist and intensivist's role in surveillance and early recognition of pandemic influenza, and in ensuring improved survival for affected patients.

Acute necrotizing encephalopathy (ANE1): rare autosomal-dominant disorder presenting as acute transverse myelitis

The term "acute transverse myelitis (ATM)" comprises various non-traumatic disorders that eventually can be associated with a focal myelopathy. Patients characteristically present with an acutely occurring paraparesis/plegia and require a comprehensive and timely diagnostic work up for the initiation of an appropriate treatment. We present a case of a 36-year-old female patient with a rare genetic disorder (ANE1: Acute Necrotizing Encephalopathy due to a RANBP2 mutation) who presented with an acute quadriplegia. Following an acute pulmonal infection, she rapidly (< 24 h) developed a severe quadriplegia (total motor score 38) with some facial sensory symptoms (perioral hypoesthesia). Magnetic resonance imaging (MRI) revealed a combination of longitudinal extensive transverse myelitis and symmetrical thalamic lesions. A work-up for infectious and systemic diseases was negative; specifically, no findings related to multiple sclerosis, neuromyelitis optica or vascular disorders. After empirical high dose steroid treatment and rehabilitation therapy, the patient gained almost normal gait and upper limb function. She was found to carry an autosomal-dominant missense mutation in the RANBP2 gene predisposing for ANE. Gene segregation was confirmed in other family members that had been affected by other episodes of acute steroid-responsive encephalopathies. We propose that a redefined diagnostic workup of ATM might include ANE1, as the frequency of this rare disorder might be underestimated.

Severe form of encephalopathy associated with 2009 pandemic influenza A (H1N1) in Japan

BACKGROUND

Every year, an estimated 200-500 children in Japan develop influenza-associated encephalopathy (IAE), and 10-30% of these children die.

OBJECTIVE

To clarify the clinical features of a severe form of acute encephalopathy seen with 2009 pandemic influenza A (H1N1).

STUDY DESIGN

This retrospective survey examined 20 children with acute encephalopathy associated with the 2009 pandemic influenza A (H1N1) who died or were in a prolonged deep coma with a flat electroencephalogram tracing and loss of spontaneous respiration. We obtained demographic, clinical, laboratory, and neuroimaging data through interviews with the attending physicians and chart reviews.

RESULTS

Subjects were 13 boys and seven girls. Their median age was 45 (range 11-200) months. Five patients had one or more pre-existing conditions. Acute encephalopathy developed within 2 days after influenza onset in 16 patients. As the initial neurological symptom, delirious behavior was seen in six children, and brief seizures in six. Eighteen patients were comatose within 6h of the onset of encephalopathy. Marked brain edema on computed tomography (CT) was seen in all but one patient. Brainstem lesions on CT were recognized in 12 patients. Sixteen patients died 0-45 (median 2.5) days after the onset of acute encephalopathy, and the others remained in deep comas without spontaneous respiration.

CONCLUSIONS

The clinical course of the patients was characterized by an onset with mild neurological symptoms and rapid deterioration of consciousness into coma. Head CT revealed marked cerebral edema, often associated with brainstem lesions.

Recurrent acute necrotizing encephalopathy in a Korean child: the first non-Caucasian case

Acute necrotizing encephalopathy is characterized by fever, seizures, acute encephalopathy, and rapid progression to coma. It is usually associated with viral illness and shows characteristic brain magnetic resonance imaging features, including symmetrical involvement of bilateral thalami, brain stem, white matter, and cerebellum. After the first report of recurrent or familial cases in 2003, similar cases were found exclusively in American and European regions. The association with Ran-binding protein 2 gene was identified in 75% of familial or recurrent cases. This report describes a previous healthy 22-month-old boy who recurrently manifested typical clinical and radiological characteristics of acute necrotizing encephalopathy. His neurological outcome worsened with repeated episodes. There was no family history of acute necrotizing encephalopathy and no mutation in the coding region of Ran-binding protein 2 (RANBP2) gene. This is the first reported case of recurrent acute necrotizing encephalopathy in a non-Caucasian family.

Prognostic factors in acute encephalopathy with reduced subcortical diffusion

OBJECTIVES

Acute encephalopathy with reduced subcortical diffusion (AED) covers a spectrum including not only typical acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) but also atypical AESD with monophasic clinical course, or more severe subtypes. Aim of this study is to analyze prognostic factors of AED.

MATERIALS & METHODS

We recruited 33 children with AED, that is, widespread diffusion restriction in cortical and subcortical structures. Their clinical courses, laboratory data, MRI, and the efficacy of treatment were analyzed retrospectively.

RESULTS

Of the 33 children, 20 were males and the mean age at diagnosis was 22 months. Eighteen children had good outcome and 15 had poor outcome. Univariate analysis showed loss of consciousness 24 h after the onset, prolonged seizure at the onset, and mechanical ventilation to be weak predictors of poor outcome. Maximal aspartate aminotransferase, alanine aminotransferase, and creatinine kinase levels were significantly higher in the poor outcome group. Multivariate analysis showed loss of consciousness 24 h after the onset and prolonged seizure at the onset to be poor predictors of AED. Treatment with steroids and/or immunoglobulins did not result in better outcome.

CONCLUSION

Prolonged seizure at the onset and loss of consciousness 24 h after the onset were seen at early stages of severe AED. Using these features, a prospective study of early intervention in AED should be conducted to further analyze the efficacy of its treatment.

Immunomodulatory therapy in recurrent acute necrotizing encephalopathy ANE1: is it useful?

Acute Necrotizing Encephalopathy (ANE) is a rare disorder characterized by fever, seizures and rapid progression to coma after the onset of a viral infection. Most cases are sporadic, however the observation of multiple cases in the same family with recurrent episodes of ANE led to the identification of a genetic form of the disorder, called ANE1, and to the discover of the causative mutation in RANBP2 gene. We report the first Italian child with ANE1 carrying the common c.1880C>T mutation in the RANBP2 gene, who presented three episodes of acute encephalopathy in the first two years of life. The child showed a less severe clinical and neuroradiological course with respect to the previously reported patients. During the acute encephalopathy episodes he was treated with steroids and immunoglobulin. A very low steroid maintenance therapy was administered after the second episode until the onset of the third. Thirty days after the last episode he started monthly intravenous immunoglobulin that might be used for prevention of viral infections. At the moment he is still continuing a low steroid maintenance therapy and monthly IVIG. We could hypothesize that the less severe clinical presentation of the third episode might be correlated to the steroid treatment or that the patient grew older. Despite there is no evidence to support that ANE1 is an immune-mediated disease, immunomodulatory therapy might be considered in the management of ANE1 cases especially in early childhood, in which a fatal course has been frequently reported. Further studies will be necessary to define the clinical, immunological and genetic aspects, as well as the outcome of immunomodulatory therapy in patients with ANE1.

Epidemiology of acute encephalopathy in Japan, with emphasis on the association of viruses and syndromes

A research committee supported by the Japanese government conducted a nationwide survey on the epidemiology of acute encephalopathy in Japan using a questionnaire. A total of 983 cases reportedly had acute encephalopathy during the past 3 years, 2007-2010. Among the pathogens of the preceding infection, influenza virus was the most common, followed by human herpesvirus-6 (HHV-6) and rotavirus. Among syndromes of acute encephalopathy, acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) was the most frequent, followed by clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS), acute necrotizing encephalopathy (ANE) and hemorrhagic shock and encephalopathy syndrome (HSES). Influenza virus was strongly associated with ANE and MERS, HHV-6 with AESD, and rotavirus with MERS. Mortality was high in ANE and HSES, but was low in AESD, MERS and HHV-6-associated encephalopathy. Neurologic sequelae were common in AESD and ANE, but were absent in MERS.

A case of acute necrotizing encephalopathy associated with parainfluenza virus infection

Acute necrotizing encephalopathy (ANE) may be suspected when a young child presents with abrupt onset of altered mental status, seizures, or both. Definitive clinical diagnosis is based on magnetic resonance imaging (MRI) results. ANE is associated with influenza virus infections. Preliminary data suggests that up to 25% of ANE patients die, and up to 25% of ANE survivors develop substantial neurologic sequelae. Here, we describe a case of a comatose 22-month-old girl who was admitted to our hospital because of febrile illness and seizures. On day 13 of her illness, she died from ANE associated with infection from parainfluenza virus. Brain MRI results indicated diffuse bilateral symmetric signal changes in both basal ganglia, thalami, periventricular white matter, pons, and cerebral white matter, as well as generalized swelling of the brain.

Acute encephalopathy with 2009 pandemic flu: comparison with seasonal flu

To clarify the features of acute encephalopathy associated with 2009 pandemic flu. We identified 51 patients with acute encephalopathy with seasonal flu from the data base accumulated by Tokai Pediatric Neurology Society. We also collected 10 patients with acute encephalopathy with 2009 pandemic flu. The clinical course, laboratory data, neuroimaging findings, treatment, and the outcome of these patients were recruited using a structured research form. These data were compared between the two groups. The age was larger in the 2009 pandemic flu group (median, 109.5months) than in the seasonal flu group (median, 44months). There was no significant difference in other demographic data, neurologic symptoms, laboratory and neuroimaging findings, and treatment. Various degrees of neurologic sequelae including death were observed in 32% of the patients in the seasonal flu group, and in 50% in the 2009 pandemic flu groups. The analyses of patients with ages of 6years or older revealed that moderate or more severe sequelae were more frequent in patients with 2009 pandemic flu. Acute encephalopathy with 2009 pandemic flu occurred mainly among children with 6years of age or older, and the outcome was worse in this age group compared with acute encephalopathy with seasonal flu.

Acute encephalopathy with bilateral thalamotegmental involvement and a benign course: a case report from Brazil

This rare encephalopathy that generally affects children is preceded by a respiratory infection and fever associated with convulsions and may progress to coma. Outcome is catastrophic in most cases. This case report describes a Brazilian child of African descent with fever, cephalea and bilateral amaurosis, who evolved to coma with pyramidal signs and associated convulsions. MRI showed diffuse, symmetrical lesions in the thalamotegmental region and brainstem. Following administration of methylprednisolone, the clinical condition of the patient improved and the brain lesions regressed, leaving the child with no current neurological deficits. This was a case of acute postinfectious encephalopathy, involving various brain structures. Outcome was favourable with no sequelae following therapy. This case was atypical due to the bilateral visual involvement and extensive encephalic lesions in a child of African descent with no neurological sequelae following therapy. No other similar cases have been reported in the literature.

Pediatric neurological complications of 2009 pandemic influenza A (H1N1)

OBJECTIVE

To analyze the spectrum of neurological manifestations in children hospitalized with pandemic influenza A H1N1 virus of 2009 (pH1N1).

DESIGN

Retrospective case series of children hospitalized from May 1, 2009, through November 30, 2009.

SETTING

Tertiary-care children's hospital in Colorado.

PATIENTS

All hospitalized patients with pH1N1 with neurological consult or diagnosis, lumbar puncture, electroencephalogram, or neuroimaging were selected as suspected cases. These were systematically reviewed and selected for final analysis if confirmed by pre-established definitions as a neurological complication.

RESULTS

Of 307 children with pH1N1, 59 were selected as having suspected cases of neurological complications. Twenty-three children were confirmed to have a neurological complication. Of these 23, 15 (65%) required intensive care monitoring. The median length of stay was 4 days. Seventeen (74%) had a preexisting neurological diagnosis. The most common manifestation was seizure with underlying neurological disease (in 62% of cases) followed by encephalopathy with or without neuroimaging changes (in 26% of cases). Results from a lumbar puncture showed elevated protein levels in 3 of 6 patients but no significant pleocytosis. Seven of the 9 electroencephalograms showed diffuse slowing, and findings from magnetic resonance imaging were abnormal in 5 of 6 children. Deaths occurred in 13% of patients, and short-term disability in 22%.

CONCLUSIONS

Children infected with pH1N1 presented with a wide spectrum of neurological manifestations, which occurred primarily in individuals with preexisting neurological conditions. These individuals had a severe disease course, evidenced by need for intensive care services and relatively high rates of mortality or neurological disability. Children with underlying neurological conditions should be particularly targeted for influenza prevention and aggressive supportive treatment at the onset of influenzalike symptoms.

Encephalitis diagnosis and management in the real world

Significant advances, especially in microbiologic diagnostics and brain imaging, have broadened our understanding of the etiology, pathogenesis, and natural history of acute encephalitis. In some instances this had led to specific therapies and preventive measures. The clinical hallmark of acute encephalitis is the triad of fever, headache, and altered mental status. Common neurologic features include disorientation or depressed level of consciousness; disturbances of behavior, speech, or executive function; and diffuse or focal neurologic signs such as cranial nerve dysfunction, hemiparesis, or seizures. These features distinguish the unusual patient with encephalitis from the more commonly encountered patient with uncomplicated meningitis who has fever, headache, and nuchal rigidity but lacks abnormal global or focal neurologic signs. Etiologies of acute encephalitis are myriad. Most are viral infections. Table 1 shows a robust but not exhaustive list of viral etiologies. Beyond this there is another robust but not exhaustive list (Table 2) of important considerations in the differential diagnosis. These include infectious agents (bacterial, fungal, parasitic, and amebic) as well as non-infectious etiologies (parainfectious, post-infectious, autoimmune, neoplastic, cerebrovascular, systemic, and other conditions). The challenge for the clinician is to rapidly hone the list and make critical management decisions by considering the specific features of the setting of the patient's illness, host susceptibility, clinical and neurologic findings, and results of laboratory and imaging studies.

The interplay of infection and genetics in acute necrotizing encephalopathy

PURPOSE OF REVIEW

Acute necrotizing encephalopathy (ANE) presents with fulminant encephalopathy and characteristic brain lesions following viral infection. The rarity and unpredictability of the disorder have significantly impaired its study. Growing recognition of ANE and the discovery of causative missense mutations in the nuclear pore gene RANBP2 give promising steps toward unraveling this disease. This review summarizes recent advances of clinical and scientific understanding of ANE.

RECENT FINDINGS

Inflammatory factors participate in the pathogenesis of ANE, but the lack of difference between influenza and noninfluenza ANE focuses attention on the abnormal host response as causative. Early treatment with steroids provides the best outcome for patients who do not have brainstem lesions. Missense mutations in RANBP2 cause the majority of familial and recurrent ANE cases, but other single-gene causes of ANE are possible for familial, recurrent, and sporadic cases.

SUMMARY

Early recognition and systematic evaluation of ANE are necessary. Modeling ANE as a genetic disorder may provide the most immediate gains in the understanding and treatment of ANE and related disorders.

Untreated recurrent acute necrotising encephalopathy associated with RANBP2 mutation, and normal outcome in a Caucasian boy

Acute necrotising encephalopathy (ANE) is a rare encephalitis-like syndrome usually reported in East Asia. This clinical syndrome tends to be triggered by viral febrile illness with rapid deterioration to seizures, coma and a generally poor outcome. Diagnosis is usually made on Magnetic Resonance Imaging (MRI). Its epidemiology is unknown largely due to under-recognition. Recurrent ANE has recently been associated with a newly discovered autosomal dominant mutation RAN-binding protein 2 now termed ANE1. There had been reports encouraging the use of empirical corticosteroids as treatment for this condition. However, there have not been any clinical trials to date. Here we report an unusual case of a Caucasian toddler who had suffered two episodes of ANE, but did not receive any specific treatment and has normal physical and cognitive outcome at 1 year follow up. He has this missense mutation in the gene of the RAN-binding protein 2 as have his mother and brother who are both well. This case adds to the worldwide literature and expands on the spectrum of outcomes in order to bring about better recognition in the Caucasian population.

Clinical spectrum and prognostic factors of acute necrotizing encephalopathy in children

This study was conducted to investigate the etiology, the clinical characteristics and prognosis of acute necrotizing encephalopathy (ANE) in Korean children. Six children (1 yr to 7 yr) patients with ANE were enrolled. They were diagnosed by clinical and radiological characteristics and their clinical data were retrospectively analyzed. In a search of clinically plausible causes, brain MRI in all patients, mitochondrial DNA studies for mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes (MELAS) and myoclonus epilepsy and ragged red fibers (MERRF) in four patients, and genomic typing on HLA DRB/HLA DQB genes in three patients were performed. All had precedent illnesses and the main initial symptoms included mental change (83%), seizures (50%), and focal deficits (50%). MRI revealed increased T2 signal density in the bilateral thalami and/or the brainstem in all patients. Mitochodrial DNA studies for MELAS and MERRF were negative in those children and HLA-DRB1*1401, HLA-DRB3*0202, and HLA-DQB1*0502 seemed to be significant. A high dose steroid was given to all patients, which seemed to be partly effective except for 2 patients. In conclusion, ANE is relatively rare, but can result in serious neurological complication in children. Early detection and appropriate treatment may lead to a better neurological outcome.

Acute necrotizing encephalopathy in 3 brothers

Acute necrotizing encephalopathy (ANE) is a devastating and rapidly progressive neurologic disorder that occurs in healthy children after common viral infections. Typically, ANE is sporadic and does not recur. However, familial (ANE1) and recurrent cases have been reported and were recently linked to mutations in RANBP2 (RAN-binding protein 2). We report here a multiply affected kindred with recurrent familial ANE. These affected male siblings (a set of twins and their older brother) all presented with prodromal fever and upper respiratory tract infection that progressed within 72 hours to seizures, coma, and ultimately death, a course that is typical of ANE. It should be noted that 1 brother was treated with early aggressive management, including corticosteroids, and he survived for an additional 5 years. This represents the second reported case of familial ANE in the United States and the only case of male siblings with consanguineous parents. We hope that early recognition and growing awareness can lead to more effective treatment and better outcomes in the future.

Acute necrotizing encephalopathy

Acute necrotizing encephalopathy (ANEC) is a rare disease well recognized in Japan but has not yet been reported from Indian subcontinent. We describe here a case of ANEC with the neuroimaging findings. P. vivax infection was detected as an associated finding and the treatment given.