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

The Spectrum of Influenza-Associated Acute Necrotizing Encephalopathy of Childhood: A Case Series

BACKGROUND

Acute necrotizing encephalopathy of childhood (ANEC) is a rare inflammatory neurological disease with characteristic neuroimaging findings commonly leading to disability or death. It is associated with a variety of infectious agents, most commonly influenza.

METHODS

This study is a retrospective case series describing three children presenting with ANEC during the 2023-2024 influenza season.

RESULTS

All patients were influenza A positive with a variable duration of prodromal infectious symptoms. Each presented with witnessed or suspected seizures and persistent encephalopathy. Initial computed tomography (CT) was unremarkable in two patients; however, on follow-up neuroimaging all evolved multifocal brain lesions, including symmetric bilateral thalamic involvement consistent with ANEC. All patients received intravenous pulse methylprednisolone, but the timing and selection of additional immunomodulatory interventions differed between patients. Outcomes spanned from slight disability to death.

CONCLUSIONS

These patients illustrate the spectrum of ANEC presentations and outcomes and underscore the importance of prompt investigations in children with persistent encephalopathy and prodromal infectious symptoms, even with unremarkable findings on initial CT. The variability in treatment and outcomes within a single center emphasizes the need for further research to establish a better pathophysiologic understanding of ANEC and optimal treatment protocols.

Long-Term Fish Oil Supplementation Attenuates Spike Wave Discharges in the Amygdala of Adult Rats with Early-Life Febrile Seizures

Background and Objectives: Febrile seizures (FS) are neuronal disturbances frequently associated with abnormal electroencephalographic activity (EEG) as spike-wave discharges (SWDs). Fish oil (FO) has high amounts of omega-3 fatty acids (θ-3), and its effects on FS alterations are poorly understood. The aim of this work was to evaluate the effect of long-term FO supplementation on the EEG of the amygdala of adult male rats with early-life FS. Materials and Methods: Progenitor female Wistar rats, from puberty to gestation and delivery, were fed daily with a commercial diet supplemented with either fish oil (FO), palm oil (PO), or deionized water (CTRL). After parturition, male pups were exposed for 30 min to hyperthermia (HP) and then returned to their dams. After weaning, pups were fed a commercial diet and the respective treatments up to 155 days of age when electrodes were implanted in the amygdala. Results: During early life HP, the PO and CTRL groups reached maximal core temperature (CT) in comparison with the FO group. Furthermore, the FO group only has fewer myoclonus and long latency to adopt an uncontrolled posture. At an adult age, the FO group with early-life FS scored shorter periods of SWDs in amygdala EEG but without seizures and presented minor values of absolute power than the PO and CTRL groups. Conclusions: In adult rats, the long-term supplementation of FO minimizes the deleterious behavioral effects caused by early-life FS and decreases the occurrence and amplitude of SWDs in the EEG of the amygdala.

Acute necrotizing encephalopathy in an adult presenting with typical imaging findings and distinctive cerebrospinal fluid characteristics: a case report

BACKGROUND

Acute necrotizing encephalopathy is a rare, clinically distinct subgroup of acute encephalopathy, which may be a complication of coronavirus disease 2019.

CASE PRESENTATION

A 22-year-old male of Han Chinese with a yellow complexion presented with fever, psychological and behavioral abnormalities, seizures, and coma. Cerebrospinal fluid tests indicated leukocytosis, high protein concentrations, and significantly elevated levels of neuron-specific enolase, interleukin-2, interleukin-6, and interleukin-8. Magnetic resonance imaging revealed restricted diffusion in the bilateral thalami and splenium of the corpus callosum, and no hemorrhagic signals were detected on susceptibility-weighted imaging. Hyperintense and hypointense lesions in the bilateral thalami, brainstem, cerebellum, and splenium of the corpus callosum were observed in T1- and T2-weighted sequences without gadolinium enhancement. At the 6-month follow-up, the T1 and T2 sequences showed significant atrophy in the cerebellar hemispheres and brachium pontis and an enlarged fourth ventricle. After symptomatic and immunotherapy treatment, the prognosis was good.

CONCLUSION

We report a rare case of a 22-year-old male diagnosed acute necrotizing encephalopathy showing typical imaging findings and distinctive cerebrospinal fluid presentation. In adults, heightened awareness of acute necrotizing encephalopathy is crucial because early recognition and treatment have the potential to enhance prognosis.

Epidemiology and treatment trends for acute encephalopathy under the impact of SARS-CoV-2 pandemic based on a prospective multicenter consecutive case registry

BACKGROUND

Acute encephalopathy is a severe condition predominantly affecting children with viral infections. The purpose of this study was to elucidate the epidemiology, treatment, and management of acute encephalopathy. The study also aimed to understand how the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has affected epidemiological trends.

METHODS

This retrospective study used the database of the Febrile Acute Convulsion and Encephalopathy registry, a prospective multicenter consecutive case registry for acute encephalopathy and febrile convulsive status epilepticus. Pediatric patients aged 0-18 years hospitalized and diagnosed with acute encephalopathy between January 2020 and August 2023 were included in this study.

RESULTS

Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) was the most common syndrome (36 cases, 27.5 %). SARS-CoV-2 was the most common pathogen (19 cases, 14.5 %), followed by influenza virus type A (15 cases, 11.5 %). Targeted temperature management was performed for 25 (69.4 %) of 36 patients with AESD; 5 (50.0 %) of 10 patients with hemorrhagic shock and encephalopathy; and only 1 (5.9 %) of 17 patients with mild encephalitis or encephalopathy with a reversible splenial lesion (MERS). High-dose corticosteroids were administered to 9 (90.0 %) of 10 patients with hemorrhagic shock and encephalopathy and 11 (30.6 %) of 36 patients with AESD.

CONCLUSIONS

The primary causative pathogen of acute encephalopathy has changed to SARS-CoV-2. AESD remains the most common syndrome. Targeted temperature management is more, whereas high-dose corticosteroid therapy is less, frequently used. No specific treatment for mild encephalitis or encephalopathy with a reversible splenial lesion has been established.

Clinical characteristics and associated factors of pediatric acute necrotizing encephalopathy: a retrospective study

BACKGROUND

In the clinic, pediatric acute necrotizing encephalopathy (ANE) primarily affects children under 5 years of age and is characterized by severe brain damage and high mortality. However, some challenges remain regarding the diagnosis and treatment of ANE. In the present study, we analyzed the clinical characteristics and related factors of ANE with the aim of providing improved diagnostic and treatment strategies.

PURPOSE

The main purpose of this study is to gain a deeper understanding of the clinical characteristics and pathophysiology of ANE through a retrospective study, and to provide clinical practitioners with more effective. diagnostic and treatment strategies to improve patient survival rates and quality of life.

METHODS

Thirty-four pediatric ANE patients admitted to Zhejiang University School of Medicine Hospital between February 2019 and December 2023 were included in this study. To identify the factors associated with mortality, clinical, laboratory and imaging data were analyzed with independent-sample t tests, Mann-Whitney U tests, Fisher exact probability tests and receiver operating characteristic curve analyses.

RESULTS

In this cohort of 34 patients, the most common symptoms were fever, seizures, altered consciousness, vomiting, diarrhea and shock. The mortality rate was 55.9%. Laboratory tests revealed that patients who died had higher creatinine, lactate, activated partial thromboplastin time, thrombin time, interleukin (IL)-6, IL-10, creatine kinase, and D-dimer than survivors. Imaging examinations predominantly revealed symmetrical lesions in the thalamus. The fatal group displayed lower Glasgow Coma Scale (GCS) scores and severe complications. Other factors related to mortality included the arterial pH, GCS score and hospitalization duration.

CONCLUSION

The most common symptoms of ANE are fever, seizures, altered consciousness, vomiting, diarrhea and shock, and ANE has a high mortality rate. The GCS score and arterial pH are critical biomarkers for assessing the severity of ANE.

Child Neurology: Acute Necrotizing Encephalopathy of Childhood Associated With Dengue: Good Neurologic Outcome Despite a Fulminant Presentation

Acute necrotizing encephalopathy of childhood (ANEC) is characterized by a rapidly progressive encephalopathy after a viral febrile illness, with multiple, symmetrical lesions in the brain including the thalami. Acute dengue fever is a known, but rare, trigger for ANEC. The clinical course of ANEC is usually fulminant and is associated with high morbidity and mortality. We describe here a prospective cohort of 5 children who presented with ANEC associated with dengue infection characterized by encephalopathy within the first week of fever, followed by a rapidly deteriorating sensorium requiring intensive care unit admission. Dengue fever was diagnosed based on a positive nonstructural protein 1 antigen test. ANEC was diagnosed based on characteristic MRI brain findings including the "trilaminar sign" in bilateral thalami combined with clinical features of severe encephalopathy, thrombocytopenia, and transaminitis. All the children required prolonged hospital stay (mean duration 30 days), with 4 of 5 children requiring mechanical ventilation (mean duration 21 days). All the children received immunomodulation with IV methylprednisolone either alone or followed by IV immunoglobulin. Although these children were bedridden at discharge (modified Rankin Scale, mRS score 4 or 5), they showed a consistent recovery in follow-up. At 6 months of follow-up, all the children were fully independent in activities of daily living (mRS scores 1-2). These cases highlight good neurologic outcomes in children with ANEC associated with dengue despite a catastrophic presentation and a protracted hospital course. The most common residual neurologic deficits noted were hand tremors and extrapyramidal dysarthria.

Two siblings with acute necrotizing encephalopathy associated with variants of LARS1

Acute necrotizing encephalopathy (ANE) is a rapidly progressive encephalopathy of unknown etiology. The underlying mechanisms are highly heterogeneous, often including genetic backgrounds. Variants of LARS1, encoding the leucyl-tRNA synthetase 1, are responsible for infantile liver failure syndrome 1. We describe two siblings with ANE caused by compound heterozygous variants of LARS1. Patient 1 was a 17-month-old girl. She presented with generalized seizure and liver dysfunction due to influenza type A infection. Brain magnetic resonance imaging on day 4 of onset showed diffuse high-intensity signals consistent with ANE. She died on day 10. Patient 2, a younger male sibling of patient 1, had mild to moderate developmental delay and growth failure at the age of 18 months. He showed a markedly elevated level of transaminases triggered by infection with human herpesvirus 6. On day 4 of onset, he had generalized seizures. Brain computed tomography showed a diffuse symmetrical hypodensity consistent with ANE. He died on day 7. Whole exome sequencing identified the compound heterozygous variants in LARS1 (NM_020117.11) as c.83_88delinsAATGGGATA, p.(Arg28_Phe30delinsLysTryAspIle) and c.1283C>T, p.(Pro428Leu) in both siblings. The severe neurologic phenotype, found in our patients, reflects the complicated pathogenesis of LARS1-related disorder.

Severe Neurological Complications With Influenza in Vietnamese Children

BACKGROUND

Influenza is a common contagious respiratory virus that primarily causes respiratory tract infections. Neurological complications associated with influenza have also been reported, mainly in pediatric populations, and may be fatal.

METHODS

A descriptive study evaluated pediatric patients who were diagnosed with severe influenza-associated neurological complications at the Tropical Pediatrics Center-Vietnam National Children's Hospital from October 2022 to February 2024.

RESULTS

In this study involving 20 patients, 80% of children were under 5 years old; 70% of patients had a history of good health. All patients had not received an influenza vaccination within 12 months. The median time from onset to neurological symptoms was 1 day. The most common neurological complication was encephalitis (16/20 patients) with symptoms included altered consciousness and seizures. Most patients had elevated levels of ALT (60%), AST (90%), LDH (94%), and ferritin (69%) in serum. The imaging of brain damage on MRI and CT scans varied in patterns and locations. There was no difference in the timing of methylprednisolone treatment within and after 48 h. The mortality rate was 20%, with 45% of patients experiencing severe sequelae.

CONCLUSIONS

IANCs are severe with damage to both white matter and central gray matter and can occur in healthy children, emphasizing the importance of vaccination to reduce the risk.

Acute necrotizing encephalopathy caused by bacterial infection

PURPOSE

Acute necrotizing encephalopathy (ANE), a rare and severe brain disorder, is typically linked to prior infections. ANE predominantly affects children, with most reported cases attributed to viral infections. However, instances of bacterial-induced ANE are infrequent. Here, we present a case of adult-onset ANE associated with bacterial infection.

CASE DESCRIPTIONS

The patient exhibited a hyperinflammatory state following a urinary tract bacterial infection, with neurological function rapidly declining into a coma as the illness progressed. Gram culture of blood suggested Escherichia coli infection. A magnetic resonance imaging (MRI) scan of the brain showed symmetrical hyperintense lesions involving bilateral thalami and pons in T2-weighted and fluid-attenuated inversion recovery images. These lesions also presented with diffuse cerebral edema and diffusion restriction and subacute hemorrhage. Based on clinical symptoms and typical brain MRI, ANE was diagnosed, and the patient underwent immunotherapy.

CONCLUSIONS

This case underscores the occurrence of ANE triggered by bacterial infection, expanding our understanding of the pathogens associated with this condition. It suggests that ANE may be an immune-mediated disorder rather than solely an infectious disease.

Acute necrotizing encephalopathy in adult patients with influenza: a case report and review of the literature

The neurological complications of influenza affect mainly the pediatric Asian population. In the category of influenza-associated encephalopathy, acute necrotizing encephalopathy (ANE) is a rapidly progressive and fulminant brain disorder associated with significant neurological sequelae and mortality. To date, only a few adult cases of influenza-associated ANE have been reported. We describe a 44-year-old woman who presented with rapid progression of consciousness impairment and recurrent generalized convulsions. Influenza was diagnosed three days prior to presentation, and infection with influenza A (H3N2) pdm09 was subsequently confirmed. A diagnosis of ANE was made based on the presence of characteristic brain MRI findings, the exclusion of central nervous system infection, and an elevated serum interleukin-6 level. Pulse steroid therapy followed by tocilizumab was initiated, which led to clinical stabilization and improvement. Genetic testing revealed that the patient carried heterozygous human leukocyte antigen DQB1 03:03 and DRB1 09:01 genotypes. An analysis of the adult cases of influenza-associated ANE in the literature and the present case revealed a wide range of ages (22-71 years), a short interval (median 3 days) between the clinical onset of influenza and ANE, and a high overall mortality rate (32%). The thalamus was the most frequent (91%) location of the lesions. Our report highlights the importance of identifying this devastating but treatable neurological complication of influenza in adults, especially those of Asian descent. As a cytokine storm is the most accepted pathogenic mechanism for ANE, cytokine-directed therapies may be promising treatments for which further investigation is warranted.

Clinical characteristics and prognosis of paediatric respiratory syncytial virus-related encephalopathy

BACKGROUND

To understand the clinical characteristics and prognosis of respiratory syncytial virus (RSV)-related encephalopathy in children.

METHODS

A retrospective analysis of the data of children who were diagnosed with RSV-related encephalopathy and admitted to the paediatric intensive care unit (PICU) of Beijing Children's Hospital between November 2016 and November 2023 was performed.

RESULTS

Four hundred and sixty-four children with RSV infection were treated in the PICU, and eight of these patients (1.7%) were diagnosed with RSV-related encephalopathy. The mean age of the patients was 24.89 (5.92 ∼ 36.86) months. Two patients had underlying diseases. The time from the onset of illness to impaired consciousness was 3 (1.88-3.75) days. Five patients had convulsions, and three patients had an epileptic status. The serum procalcitonin (PCT) level was 1.63 (0.24, 39.85) ng/ml for the eight patients, and the cerebrospinal fluid (CSF) protein level was 232 (163 ∼ 848) g/L. Among the 8 patients, four patients underwent electroencephalogram (EEG) monitoring or examination. One patient showed continuous low-voltage, nonresponsive activity, and another patient displayed persistent slow waves, the remaining two patients had negative results. One patient had a combination of acute necrotizing encephalopathy (ANE) and acute encephalopathy with biphasic seizures and late reduced diffusion (AESD). Additionally, one patient had ANE, and another had acute brain swelling (ABS). One patient died in the hospital, and the other seven patients were discharged with improvement. Routine follow-up was conducted for 4.58(0.5 ∼ 6.50) years, and all patients fully recovered.

CONCLUSIONS

RSV-related encephalopathy could have varying clinical manifestations, and some types, such as ANE and ABS, are dangerous and can lead to death.

Identification of neurological complications in childhood influenza: a random forest model

BACKGROUND

Among the neurological complications of influenza in children, the most severe is acute necrotizing encephalopathy (ANE), with a high mortality rate and neurological sequelae. ANE is characterized by rapid progression to death within 1-2 days from onset. However, the knowledge about the early diagnosis of ANE is limited, which is often misdiagnosed as simple seizures/convulsions or mild acute influenza-associated encephalopathy (IAE).

OBJECTIVE

To develop and validate an early prediction model to discriminate the ANE from two common neurological complications, seizures/convulsions and mild IAE in children with influenza.

METHODS

This retrospective case-control study included patients with ANE (median age 3.8 (2.3,5.4) years), seizures/convulsions alone (median age 2.6 (1.7,4.3) years), or mild IAE (median age 2.8 (1.5,6.1) years) at a tertiary pediatric medical center in China between November 2012 to January 2020. The random forest algorithm was used to screen the characteristics and construct a prediction model.

RESULTS

Of the 433 patients, 278 (64.2%) had seizures/convulsions alone, 106 (24.5%) had mild IAE, and 49 (11.3%) had ANE. The discrimination performance of the model was satisfactory, with an accuracy above 0.80 from both model development (84.2%) and internal validation (88.2%). Seizures/convulsions were less likely to be wrongly classified (3.7%, 2/54), but mild IAE (22.7%, 5/22) was prone to be misdiagnosed as seizures/convulsions, and a small proportion (4.5%, 1/22) of them was prone to be misdiagnosed as ANE. Of the children with ANE, 22.2% (2/9) were misdiagnosed as mild IAE, and none were misdiagnosed as seizures/convulsions.

CONCLUSION

This model can distinguish the ANE from seizures/convulsions with high accuracy and from mild IAE close to 80% accuracy, providing valuable information for the early management of children with influenza.

Pediatric neuroinflammatory diseases in the intensive care unit

Inflammatory disorders of the central nervous system (CNS) include a wide spectrum of autoimmune, autoinflammatory, and paraneoplastic diseases. While many affected patients require acute hospital admission, a subset may present with severe neurological symptoms requiring intensive care unit (ICU) escalation due to disordered consciousness, respiratory failure, status epilepticus, intracranial hypertension, and/or severe autonomic dysregulation.

Ferritin as an Effective Predictor of Neurological Outcomes in Children With Acute Necrotizing Encephalopathy

BACKGROUND

Acute necrotizing encephalopathy (ANE) is a fulminant disease with poor prognosis. Cytokine storm is the important phenomenon of ANE that affects the brain and multiple organs. The study aimed to identify whether hyperferritinemia was associated with poor prognosis in patients with ANE.

METHODS

All patients with ANE had multiple symmetric lesions located in the bilateral thalami and other regions such as brainstem tegmentum, cerebral white matter, and cerebellum. Neurological outcome at discharge was evaluated by pediatric neurologists using the Pediatric Cerebral Performance Category Scale. All risk factors associated with poor prognosis were further analyzed using receiver operating characteristic curve analysis.

RESULTS

Twenty-nine patients with ANE were enrolled in the current study. Nine (31%) patients achieved a favorable neurological outcome, and 20 (69%) patients had poor neurological outcomes. results The group of poor neurological outcome had significantly higher proportion of shock on admission and brainstem involvement. Based on multivariate logistic regression analysis, ferritin, aspartate aminotransferase (AST), and ANE severity score (ANE-SS) were the predictors associated with outcomes. The appropriate cutoff value for predicting neurological outcomes in patients with ANE was 1823 ng/mL for ferritin, 78 U/L for AST, and 4.5 for ANE-SS. Besides, comparison analyses showed that higher level of ferritin and ANE-SS were significantly correlated with brainstem involvement (P < 0.05).

CONCLUSIONS

Ferritin may potentially be a prognostic factor in patients with ANE. Hyperferritinemia is associated with poor neurological outcomes in patients with ANE and ferritin levels more than 1823 ng/mL have about eightfold increased risk of poor neurological outcome.

A Case of Acute Necrotizing Encephalopathy With Multiple Organ Failure Following COVID-19

Neurological complications are frequent non-respiratory complications associated with coronavirus disease 2019 (COVID-19), and acute encephalopathy (AE) has been reported to occur in 2.2% of patients. Among many phenotypes of AEs, acute necrotizing encephalopathy (ANE) is associated with multiple organ failure (MOF), leading to severe neurological morbidity and mortality. A previously healthy seven-year-old girl presented with a one-day history of fever followed by 12 hours of vomiting and altered consciousness. On arrival, the patient was in shock. Blood tests revealed severe acute liver failure and kidney injury, accompanied by coagulopathy. The serum interleukin-6 levels were also elevated. PCR testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was positive. A head CT scan showed heterogeneous low-density areas in the bilateral thalamus, without brainstem involvement. She was diagnosed as ANE complicated with MOF (ANE severity score = 6). Intravenous methylprednisolone and therapeutic plasma exchange (TPE) were initiated with neurocritical care. After the introduction of TPE, hemodynamics improved rapidly, followed by gradual improvement in neurological manifestations. Upon follow-up after two months, no neurological or systemic sequelae were noted. Although further studies are needed, our case suggests that early immunomodulatory therapy and TPE may have contributed to the improvement in ANE and MOF associated with COVID-19.

Clinical characteristics and prognostic analysis of acute necrotizing encephalopathy of childhood: a retrospective study at a single center in China over 3 years

Objective

Acute Necrotizing Encephalopathy of Childhood (ANEC) is a rare, fulminant neurological disease in children with unknown mechanisms and etiology. This study summarized the clinical characteristics, treatment, and prognosis of ANEC through a retrospective analysis, providing insights into the ANEC early diagnosis and prognosis assessment.

Methods

Clinical data of children diagnosed with ANEC at the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University from July 1, 2020, to June 30, 2023, were retrospectively analyzed.

Results

There were 25 cases, 14 males and 11 females, with a median age of 3 years. Hospital admissions were mainly in the winter (14/25, 56%) and spring (9/25, 36%). All patients presented with varying degrees of fever and altered consciousness, with 92% (23/25) experiencing high body temperatures (>39.1°C) and 88% (22/25) having a Glasgow coma scale (GCS) score of ≤8. Seizures were observed in 88% (22/25) of patients. Laboratory findings indicated 100% B lymphocyte activation (14/14), and 78% (14/18) of patients showed cytokine storm (interleukin (IL)-6, IL-8, IL-10, interferon (IFN)-α). Neuroimaging showed symmetrical thalamus involvement, commonly involving basal ganglia and brainstem regions. Viral infection (23/24, 96%) was the predominant etiological finding, with 42% (10/24) of cases due to SARS-CoV-2 infection and 42% (10/24) to influenza A virus infection. Multi-organ dysfunction occurred in 68% (17/25) of patients, and 52% (13/25) died. Correlation analysis revealed the death group exhibited higher proportion of male, lower GCS scores, higher IL-6 level and a greater likelihood of associated brainstem impairment (p < 0.05).

Conclusion

ANEC is more prevalent in the winter and spring, and its etiology may be associated with B lymphocyte activation and cytokine storm following viral infections. Clinical manifestations lack specific features, with fever, consciousness disturbances, and seizures being the main presentations, particularly in cases of high fever and hyperpyrexia. ANEC progresses rapidly and has a high mortality rate. The child's gender, GCS score, IL-6 levels, and the presence of brainstem involvement can serve as important risk factors for assessing the risk of mortality.

Recurrent infection triggered encephalopathy syndrome in a pediatric patient with RANBP2 mutation and severe acute respiratory syndrome coronavirus 2 infection

Introduction

Acute necrotizing encephalopathy (ANE), a fatal subtype of infection-triggered encephalopathy syndrome (ITES), can be triggered by many systemic infections. RANBP2 gene mutations were associated with recurrent ANE.

Case presentation

Here we report a 1-year-old girl with recurrent ITES and RANBP2 mutation. She was diagnosed with influenza-associated encephalopathy and made a full recovery on the first episode. After severe acute respiratory syndrome coronavirus 2 infection, the patient presented with seizures and deteriorating mental status. Brain magnetic resonance imaging revealed necrotic lesions in bilateral thalami and pons. Methylprednisolone, immunoglobulin, and interleukin 6 inhibitors were administered. Her consciousness level was improved at discharge. Nineteen cases of 2019 coronavirus disease-related ANE have been reported, of which 22.2% of patients died and 61.1% had neurologic disabilities. RANBP2 gene mutation was found in five patients, two of whom developed recurrent ITES.

Conclusion

Patients with RANBP2 mutations are at risk for recurrent ITES, may develop ANE, and have a poor prognosis after relapse.

Possible Toxin-Induced Acute Necrotising Encephalitis (ANE) With Secondary Vasculopathy and Paroxysmal Autonomic Instability With Dystonia (PAID) Syndrome

Acute necrotising encephalitis (ANE) is a rare and life-threatening disorder typically associated with viral pathogens triggering an inflammatory response. It is characterised by rapid neurological deterioration linked to a cytokinetic storm which radiologically manifests with cerebral radiological changes. We present a unique case not previously documented of an immunocompetent 23-year-old male who survived the course of ANE, with widespread involvement of the brain including the deep white matter, cortex, superior frontal gyrus, occipital lobe and cerebellum. His disease course was complicated by a ventilator-associated empyema, paroxysmal autonomic instability with dystonia (PAID) syndrome) and livedo reticularis which cumulatively resulted in a poor neurological outcome.

Rapid and inexpensive bedside diagnosis of RAN binding protein 2-associated acute necrotizing encephalopathy

Acute necrotizing encephalopathy 1 (ANE1) is a very rare disorder associated with a dominant heterozygous mutation in the RANBP2 (RAN binding protein 2) gene. ANE1 is frequently triggered by a febrile infection and characterized by serious and irreversible neurological damage. Although only a few hundred cases have been reported, mutations in RANBP2 are only partially penetrant and can occur de novo, suggesting that their frequency may be higher in some populations. Genetic diagnosis is a lengthy process, potentially delaying definitive diagnosis. We therefore developed a rapid bedside qPCR-based tool for early diagnosis and screening of ANE1 mutations. Primers were designed to specifically assess RANBP2 and not RGPD (RANBP2 and GCC2 protein domains) and discriminate between wild-type or mutant RANBP2. Nasal epithelial cells were obtained from two individuals with known RANBP2 mutations and two healthy control individuals. RANBP2-specific reverse transcription followed by allele-specific primer qPCR amplification confirmed the specific detection of heterozygously expressed mutant RANBP2 in the ANE1 samples. This study demonstrates that allele-specific qPCR can be used as a rapid and inexpensive diagnostic tool for ANE1 using preexisting equipment at local hospitals. It can also be used to screen non-hospitalized family members and at risk-population to better establish the frequency of non-ANE-associated RANBP2 mutations, as well as possible tissue-dependent expression patterns.

Systematic review registration

The protocol was registered in the international prospective register of systematic reviews (PROSPERO- CRD42023443257).

Acute Necrotizing Encephalopathy in Adult Patients With COVID-19: A Systematic Review of Case Reports and Case Series

BACKGROUND AND PURPOSE

Acute necrotizing encephalopathy (ANE) is a rare neurological disorder that is often associated with viral infections. Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a few COVID-19-associated ANE cases have been reported. Since very little is known about ANE, the present study aimed to determine the clinical, biochemical, and radiological characteristics of affected patients.

METHODS

A search was conducted on PubMed, Scopus, Embase, and Web of Science databases for articles published up to August 30, 2022 using relevant keywords. Case reports and series in the English language that reported ANE in adult patients with COVID-19 confirmed by reverse transcription polymerase chain reaction were included in this study. Data on the demographic, clinical, laboratory, and radiological characteristics of patients were extracted and analyzed using the SPSS software (version 26).

RESULTS

The study included 30 patients (18 males) with COVID-19 and ANE who were aged 49.87±18.68 years (mean±standard deviation). Fever was the most-prevalent symptom at presentation (66.7%). Elevated C-reactive protein was observed in the laboratory assessments of 13 patients. Computed tomography and magnetic resonance imaging were the most-common radiological modalities used for brain assessments. The most commonly prescribed medications were methylprednisolone (30%) and remdesivir (26.7%). Sixteen patients died prior to discharge.

CONCLUSIONS

The diagnosis of COVID-19-associated ANE requires a thorough knowledge of the disease. Since the clinical presentations of ANE are neither sensitive nor specific, further laboratory and brain radiological evaluations will be needed to confirm the diagnosis. The suspicion of ANE should be raised among patients with COVID-19 who present with progressive neurological symptoms.

Acute necrotizing encephalopathy associated with COVID-19: case series and systematic review

Acute necrotizing encephalopathy (ANE) is a rare neurological complication related to COVID-19. Here we present a case series of six Chinese cases with ANE associated with COVID-19 and review all reported cases in the literature. A total of six cases with ANE related to COVID-19 were enrolled in this study. Clinical manifestations, neuroimaging data, treatment and outcomes of these patients were analyzed. A literature review was performed in Pubmed and Embase and 25 cases with clinical and neuroimaging data were collected and analyzed. Among our six cases, the age of onset ranged from 15 to 56 years, with a male-to-female ratio of nearly 1:1. All patients presented with reduced consciousness. Elevated interleukin 6 in serum and/or cerebrospinal fluid (CSF) was detected in four patients. Two patients improved clinically after intravenous methylprednisolone and intravenous immunoglobulin (IVIG). Based on the literature review, the majority of cases were from Europe and the United States (60%). Two age peaks at 10-20 years (20%) and 50-60 years (28%) were observed. Two cases were found with a heterozygous Thr585Met mutation. The mortality of ANE caused by COVID-19 was 42%. The use of IVIG in combination with other immunotherapies was related to better outcome (P = 0.041) and both two patients who received Tocilizumab survived. This is the first Chinese case series about ANE associated with COVID-19. Elevated serum and CSF interlukin-6 were found in certain cases. The mortality and morbidity rates remained high although prompt immunotherapy could improve the outcomes.

Case report: Acute necrotizing encephalopathy: a report of a favorable outcome and systematic meta-analysis of outcomes with different immunosuppressive therapies

Acute Necrotizing Encephalopathy (ANE) is a condition characterized by symmetric, bilateral lesions affecting the thalamus and potentially other areas of the brain following an acute febrile illness. It manifests clinically as abrupt development of encephalopathy, or alteration in mental status that often includes development of seizures and progression to coma. Treatment strategies combine immunosuppressive therapies and supportive care with varying levels of recovery, however there are no universally accepted, data-driven, treatment algorithms for ANE. We first report a case of a previously healthy 10-year-old female with acute onset diplopia, visual hallucinations, lethargy, and seizures in the setting of subacute non-specific viral symptoms and found to have bilateral thalamic and brainstem lesions on MRI consistent with ANE. She was treated with a combination of immunomodulatory therapies and ultimately had a good outcome. Next, we present a meta-analysis of 10 articles with a total of 158 patients meeting clinical and radiographic criteria for ANE. Each article reported immunosuppressive treatments received, and associated morbidity or mortality outcome for each individual patient. Through our analysis, we confirm the effectiveness of high-dose, intravenous, methylprednisolone (HD-IV-MP) therapy implemented early in the disease course (initiation within 24 h of neurologic symptom onset). There was no significant difference between patients treated with and without intravenous immunoglobulin (IVIG). There was no benefit of combining IVIG with early HD-IV-MP. There is weak evidence suggesting a benefit of IL-6 inhibitor tocilizumab, especially when used in combination with early HD-IV-MP, though this analysis was limited by sample size. Finally, plasma exchange (PLEX) improved survival. We hope this meta-analysis will be useful for clinicians making treatment decisions for patients with this potentially devastating condition.

Bibliometric analysis of publication trends and topics of influenza-related encephalopathy from 2000 to 2022

BACKGROUND

Influenza-related encephalopathy is a rapidly progressive encephalopathy that usually presents during the early phase of influenza infection and primarily manifests as central nervous system dysfunction. This study aimed to analyze the current research status and hotspots of influenza-related encephalopathy since 2000 through bibliometrics analysis.

METHODS

The Web of Science Core Collection (WOSCC) was used to extract global papers on influenza-related encephalopathy from 2000 to 2022. Meanwhile, the VOSviewer and CiteSpace software were used for data processing and result visualization.

RESULTS

A total of 561 published articles were included in the study. Japan was the country that published the most articles, with 205 articles, followed by the United States and China. Okayama University and Tokyo Medical University published the most articles, followed by Nagoya University, Tokyo University, and Juntendo University. Based on the analysis of keywords, four clusters with different research directions were identified: "Prevalence of H1N1 virus and the occurrence of neurological complications in different age groups," "mechanism of brain and central nervous system response after influenza virus infection," "various acute encephalopathy" and "diagnostic indicators of influenza-related encephalopathy."

CONCLUSIONS

The research progress, hotspots, and frontiers on influenza-related encephalopathy after 2000 were described through the visualization of bibliometrics. The findings will lay the groundwork for future studies and provide a reference for influenza-related encephalopathy. Research on influenza-related encephalopathy is basically at a stable stage, and the number of research results is related to outbreaks of the influenza virus.

Timing of therapeutic interventions against infection-triggered encephalopathy syndrome: a scoping review of the pediatric literature

Our goal was to conduct a scoping review of the literature on the treatment of infection-triggered encephalopathy syndrome/acute encephalopathy in children, focusing on treatment targets and treatment initiation timing. We performed literature searches using PubMed for articles reporting treatments of infection-triggered encephalopathy syndrome/acute encephalopathy. We included articles describing specific treatments for acute encephalopathy with control groups. For the purpose of searching new therapies only experimentally tried in the case series, we also included case series studies without control groups in this review, if the studies contained at least two cases with clear treatment goals. Therapies were classified based on their mechanisms of action into brain protection therapy, immunotherapy, and other therapies. We operationally categorized the timing of treatment initiation as T1 (6-12 h), T2 (12-24 h), T3 (24-48 h), and T4 (>48 h) after the onset of seizures and/or impaired consciousness. Thirty articles were included in this review; no randomized control study was found. Eleven retrospective/historical cohort studies and five case-control studies included control groups with or without specific therapies or outcomes. The targeted conditions and treatment timing varied widely across studies. However, the following three points were suggested to be effective in multiple studies: (1) Careful seizure management and targeted temperature management within 12 h (T1) of onset of febrile seizure/prolonged impaired consciousness without multiple organ failure may reduce the development of acute encephalopathy with biphasic seizures and late reduced diffusion; (2) immunotherapy using corticosteroids, tocilizumab, or plasma exchange within 24 h (T1-T2) of onset of acute necrotizing encephalopathy may reduce sequelae; and (3) anakinra therapy and ketogenic diet demonstrate little evidence of neurologic sequelae reduction, but may reduce seizure frequency and allow for weaning from barbiturates, even when administered weeks (T4) after onset in children with febrile infection-related epilepsy syndrome. Although available studies have no solid evidence in the treatment of infection-triggered encephalopathy syndrome/acute encephalopathy, this scoping review lays the groundwork for future prospective clinical trials.

Coronavirus or Cholangitis? An Acute Necrotizing Encephalopathy Caused by COVID-19

A 63-year-old Japanese woman presented to the emergency room with a fever and altered mental status. She was diagnosed as acute cholangitis and coronavirus disease 2019 (COVID-19). On the second day, her consciousness level deteriorated. The patient was finally diagnosed with acute necrotizing encephalopathy (ANE). This case illustrated ANE caused by COVID-19 that co-occurred with acute cholangitis. ANE is a subtype of acute encephalitis/encephalopathy, sometimes related to COVID-19. ANE shares some clinical features with acute cholangitis. COVID-19 and bacterial infections may coexist, thus complicating an accurate diagnosis. Physicians should avoid overlooking life-threatening febrile conditions even if the diagnosis of COVID-19 is confirmed.

Treatment of severe acute necrotizing encephalopathy of childhood with interleukin-6 receptor blockade in the first 24 h as add-on immunotherapy shows favorable long-term outcome at 2 years

BACKGROUND

Acute necrotizing encephalopathy (ANE) of childhood is a rare and devastating infection-associated acute encephalopathy. While there are no consensus treatments for ANE, recent case reports suggest a beneficial role for the use of tocilizumab, a recombinant humanized monoclonal antibody against the interleukin-6 (IL-6) receptor. The correlation of the timing of add-on tocilizumab in relation to long-term outcome has not been reported.

METHODS

We report on the timing of administration of tocilizumab in two patients classified as high-risk using the ANE severity score (ANE-SS) with respect to the long-term outcome at 2 years.

RESULTS

Case 1 was a 19-month-old previously well boy who presented to a tertiary children's hospital with seizures, evolving status dystonicus and shock. Case 2 was a three-year-old boy who presented to a peripheral hospital with fever, sepsis and encephalopathy. The patients were transferred to the tertiary intensive care unit and MRI confirmed ANE with extensive brainstem involvement. Case 1 received intravenous immunoglobulin (IVIg), methylprednisolone and tocilizumab at 21, 39 and 53 h respectively. His modified Rankin scale (mRS) at discharge and two years was unchanged at 5. The functional independence measure - for children (WeeFIM) at two years was very low (19/126). Case 2 received dexamethasone at 1 h, methylprednisolone at 21 h and IVIg and tocilizumab at 22 h. The mRS at discharge and two years was 4 and 3 respectively. The WeeFIM score at two years showed substantial improvement (96/126).

CONCLUSION

The very early use of interleukin-6 blockade as 'add-on' immunotherapy in the first 24 h demonstrates potential for improving the long-term outcome in patients classified as high-risk using the ANE-SS.

Pathogenesis and Management of Acute Necrotizing Encephalopathy

INTRODUCTION

During the COVID-19 pandemic, many cases of acute necrotizing encephalopathy (ANE) secondary to COVID-19 have been reported. ANE is characterized by a rapid onset, a fulminant course, and low morbidity and fatality rates. Therefore, clinicians need to be vigilant for such disorders, especially during the influenza virus and COVID-19 epidemics.

AREAS COVERED

The authors summarize the most recent studies on the clinical spectrum and treatment essentials of ANE to provide references for prompt diagnosis and improved treatment of this rare but fatal disease.

EXPERT OPINION

ANE is a type of necrotizing lesion of the brain parenchyma. There are two major types of reported cases. One is isolated and sporadic ANE, which is primarily caused by viral infections, particularly influenza and HHV-6 virus. The other type is familial recurrent ANE, which is caused by RANBP2 gene mutations. ANE patients have rapid progression and a very poor prognosis, with acute brain dysfunction occurring within days of viral infection and requiring admission to the intensive care unit. Clinicians still need to investigate and find solutions for the problems of early detection and treatment of ANE.

Human Herpesvirus-6 Encephalitis Associated With Acute Necrotizing Encephalopathy in an Immunocompetent Child: A Case Report and Literature Review

Human herpesvirus type 6 (HHV-6) is a DNA virus considered a member of the Herpesviridae family. HHV-6 is acquired early in life, when it may cause roseola infantum and nonspecific febrile illnesses which is usually a self-limiting disease before the age of two. Primary HHV-6 encephalitis and acute necrotizing encephalopathy (ANE) are rare diseases to occur in immunocompetent children. We describe an unusual case of HHV-6 encephalitis with mixed features of acute necrotizing encephalopathy and acute disseminated encephalomyelitis and contextualize it with a review of the literature on HHV-6 encephalitis in immunocompetent children. Although the incidence of primary HHV-6 encephalitis is rare in immunocompetent children, HHV-6 encephalitis associated with acute necrotizing encephalopathy is a devastating disease, highly fatal and neurologically damaging disease. Therefore, early testing and diagnosis are crucial as well as effective management of encephalitis with antiviral therapy is highly recommended.

Risk factors for mortality in fulminant acute necrotizing encephalopathy following influenza A in an adolescent boy

Acknowledging the risk factors of mortality and morbidity of each disease is effective for its final outcome. Recognizing these cases can have the value of preventing the occurrence of unfortunate events, such as not recommending the use diclofenac in an influenza epidemic.

Brain Hypothermia Therapy and Targeted Temperature Management for Acute Encephalopathy in Children: Status and Prospects

In adult intensive care, brain hypothermia therapy (BHT) was reported to be effective in neuroprotection after resuscitation and cardiac arrest. By contrast, in neonatal intensive care, the pathophysiology of brain damage caused by hypoxic-ischemic encephalopathy (HIE) is attributed to circulatory disturbances resulting from ischemia/reperfusion, for which neonatal brain cryotherapy is used. The International Liaison Committee on Resuscitation, 2010, recommends cerebral cryotherapy for HIE associated with severe neonatal pseudoparenchyma death. The usefulness of BHT for neuroprotection in infants and children, especially in pediatric acute encephalopathy, is expected. Theoretically, BHT could be useful in basic medical science and animal experiments. However, there are limitations in clinical planning for treating pediatric acute encephalopathy. No international collaborative study has been conducted, and no clinical evidence exists for neuroprotection using BHT. In this review, we will discuss the pathogenesis of neuronal damage in hypoxic and hypoperfused brains; the history of BHT, its effects, and mechanisms of action; the success of BHT; cooling and monitoring methods of BHT; adverse reactions to BHT; literature on BHT. We will review the latest literature on targeted temperature management, which is used for maintaining and controlling body temperature in adults in intensive care. Finally, we will discuss the development of BHT and targeted temperature management as treatments for pediatric acute encephalopathy.

Changes in the treatment of pediatric acute encephalopathy in Japan between 2015 and 2021: A national questionnaire-based survey

BACKGROUND

Although acute encephalopathy (AE) is the most serious disorder associated with a viral infection in childhood and often causes death or neurological sequelae, standard treatments have not been established. In 2016, the Japanese Society of Child Neurology published the "Guidelines for the Diagnosis and Treatment of Acute Encephalopathy in Childhood 2016" (AE GL 2016). We conducted a questionnaire survey to evaluate the status of the treatment of pediatric AE in 2021 and the changes in treatment before and after the publication of the AE GL 2016.

METHODS

In October 2021, questionnaires were mailed via the web to members of two mailing lists who were involved in the practice of pediatric neurological disorders.

RESULTS

Most Japanese physicians (98 %) engaged in the treatment of pediatric AE used the AE GL 2016 as a clinical reference. From 2015 to 2021, the number of institutions that implemented targeted temperature management (TTM), vitamin administration, and continuous electroencephalographic monitoring increased significantly. Regarding the targeted temperature for TTM, the proportion of patients who were treated with normothermia (36.0-37.0 °C) increased from 2015 (55 %) to 2021 (79 %). The use of corticosteroids in patients with AE caused by a cytokine storm, which is recommended in the AE GL 2016, had already been implemented in most institutions by 2015.

CONCLUSION

The AE GL 2016 could be used to disseminate the knowledge accumulated to date. Evidence of the efficacy and proper indication criteria for the treatment of AE is insufficient and must be further accumulated.

Factors associated with outcomes of severe acute necrotizing encephalopathy: A multicentre experience in Malaysia

This case series compared clinical variables and various combinations of immunotherapy received with outcomes of patients with severe acute necrotizing encephalopathy (ANE). We performed a retrospective review of clinical variables, immunotherapy received, and outcomes (based on the modified Rankin Scale) in Malaysia between February 2019 and January 2020. Twenty-seven children (12 male), aged 7 months to 14 years (mean 4 years) at diagnosis were included. Of these, 23 had an ANE severity score of 5 to 9 out of 9 (high risk). Eleven patients received tocilizumab (four in combination with methylprednisolone [MTP], seven with MTP + intravenous immunoglobulin [IVIG]) and 16 did not (two received MTP alone, 14 received MTP + IVIG). Nine died. Among the survivors, six had good outcomes (modified Rankin Score 0-2) at 6 months follow-up. All patients who received tocilizumab in combination with MTP + IVIG survived. Twenty children received first immunotherapy within 48 hours of admission. No significant association was found between the timing of first immunotherapy with outcomes. Those with brainstem dysfunction (p = 0.016) were observed to have poorer outcomes. This study showed a trend towards better survival when those with severe ANE were treated with tocilizumab in combination with MTP + IVIG. However, larger studies will be needed to determine the effect of this regime on the long-term outcomes.

SARS-CoV-2-Related Acute Necrotizing Encephalopathy of Childhood With Good Response to Tocilizumab in an Adolescent

BACKGROUND

Acute necrotizing encephalopathy of childhood (ANEC) is a rare parainfectious neurological disorder. ANEC is associated with a high mortality rate and poor neurological outcomes. ANEC is postulated to arise from immune-mediated or metabolic processes driven by viral infections. Although there have been some case reports of acute necrotizing encephalopathy with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) coinfection in adults, paediatric cases are rare.

METHODS

A single case report of SARS-CoV-2-related ANEC in an 11-year-old boy is presented through retrospective chart review. Literature search was performed using PubMed, Embase, Cochrane database, and Google Scholar to compare and analyze similar cases of parainfectious immune-mediated encephalopathies related to SARS-CoV-2 in children.

RESULTS

An 11-year-old boy with acute SARS-CoV-2 infection presented with ophthalmoplegia, ataxia, and aphasia. Neuroimaging findings demonstrated significant swelling and signal changes in bilateral thalami, brainstem, and cerebellar hemispheres, consistent with ANEC. His high ANEC Severity Score indicated poor neurological prognosis. Treatment with a combination of early steroid therapy, intravenous immunoglobulin therapy, and targeted interleukin 6 (IL-6) blockade yielded good neurological improvements. Literature search identified 19 parainfectious immune-mediated neurological disorders related to SARS-CoV-2 in children. The only other pediatric ANEC case identified was postinfectious and thus not included.

CONCLUSIONS

This is the first report of a pediatric case of SARS-CoV-2-related ANEC, which responded well to early immunotherapy, including IL-6 blockade. Early immunotherapy with IL-6 blockade can be considered as an adjunct in managing severe ANEC.

Pathogenesis and Preventive Tactics of Immune-Mediated Non-Pulmonary COVID-19 in Children and Beyond

The COVID-19 pandemic has evolved to immune escape and threatened small children and the elderly with a higher severity and fatality of non-pulmonary diseases. These life-threatening non-pulmonary COVID-19 diseases such as acute necrotizing encephalopathies (ANE) and multisystem inflammatory syndrome in children (MIS-C) are more prevalent in children. However, the mortality of multisystem inflammatory syndrome in adults (MIS-A) is much higher than that of MIS-C although the incidence of MIS-A is lower. Clarification of immunopathogenesis and genetic susceptibility of inflammatory non-pulmonary COVID-19 diseases would provide an appropriate guide for the crisis management and prevention of morbidity and fatality in the ongoing pandemic. This review article described three inflammatory non-pulmonary COVID-19 diseases including (1) meningoencephalitis (ME), (2) acute necrotizing encephalopathies (ANE), and (3) post-infectious multisystem inflammatory syndrome in children (MIS-C) and in adults (MIS-A). To prevent these life-threatening non-pulmonary COVID-19 diseases, hosts carrying susceptible genetic variants should receive prophylactic vaccines, avoid febrile respiratory tract infection, and institute immunomodulators and mitochondrial cocktails as early as possible.

Rotavirus infection-associated central nervous system complications: clinicoradiological features and potential mechanisms

Despite the introduction of vaccines in 2006, rotavirus remains one of the most common causes of pediatric gastroenteritis worldwide. While many studies have conclusively shown that rotavirus infection causes gastroenteritis and is associated with various extraintestinal manifestations including central nervous system (CNS) complications, extraintestinal manifestations due to rotavirus infection have been relatively overlooked. Rotavirus infection-associated CNS complications are common in children and present with diverse clinicoradiological features. Rotavirus infection-associated CNS complications can be classified based on clinical features and brain magnetic resonance imaging findings, particularly lesion location on diffusion-weighted imaging. Common clinicoradiological features of rotavirus infection-associated CNS complications include: (1) benign convulsions with mild gastroenteritis; (2) acute encephalopathies/encephalitis, such as mild encephalopathy with a reversible splenial lesion, acute encephalopathy with biphasic seizures and late reduced diffusion, and acute necrotizing encephalopathy; (3) acute cerebellitis; and (4) neonatal rotavirus-associated leukoencephalopathy. The precise mechanism underlying the development of these complications remains unknown despite a number of clinical and laboratory studies. Here we review the diverse clinicoradiological features of rotavirus infection-associated CNS complications and propose a hypothesis of their pathophysiology.

Adult-onset Still's disease with concurrent acute necrotizing encephalopathy: a case report

Background

Acute necrotizing encephalopathy (ANE) is a rare encephalopathy characterized by multiple symmetrical brain lesions, mainly involving thalami. Adult-onset Still’s disease (AOSD) is a rare systemic inflammatory condition of unknown cause characterized by fever, sore throat, rash and joint pain. Both entities are considered to be triggered by infections and associated with hypercytokinemia.

Case presentation

A 46-year-old male was diagnosed with AOSD at local hospital because of 3-week-long high fever, sore throat, arthralgia, transient skin rash, lymphadenopathy, leukocytosis, hyperferritinemia, and absence of antinuclear antibodies (ANA) and rheumatoid factor (RF). Corticosteroids were not used because of delayed diagnosis. Three weeks after the onset, the patient suddenly fell unconscious and was transferred to our hospital. Brain CT and MRI revealed symmetrical lesions involving thalami, striatum and brain stem, consistent with ANE. One day after admission, his condition aggravated and brain CT revealed hemorrhage in the lesions. He died 3 days after admission.

Conclusion

We report a rare case of ANE preceded by AOSD. The underlying mechanism is still unclear. Early recognizing of the two conditions is difficult but prognostically important.

Outcomes in influenza and RANBP2 mutation-associated acute necrotizing encephalopathy of childhood

AIM

To evaluate clinical and imaging features in patients with acute necrotizing encephalopathy of childhood (ANEC) to identify predictors of RANBP2 mutations, influenza association, and long-term outcomes.

METHOD

A retrospective chart review in patients with ANEC (2012-2020) seen at a tertiary pediatric center was performed. Children were included if they had acute inflammatory lesions in the basal ganglia and pons. Variables included presenting features, imaging characteristics, RANBP2 gene testing, nasopharyngeal swab findings, therapies, and long-term outcomes.

RESULTS

Twenty patients were included (average age at presentation 3y 6mo, interquartile range  3y 7mo, SD  2y 8mo; 14 females, six males). Three of the 20 experienced recurrences; one of the 20 died. Ten patients were influenza positive. Seven patients were RANBP2 mutation positive. A higher likelihood of hemorrhage was observed in patients who were influenza positive compared to influenza negative (p=0.048). Patients with influenza had a higher degree of thalamic hemorrhage (2, p=0.035) and greater extent of diffusion restriction (3, p=0.035) in semiquantitive analysis.

INTERPRETATION

Children with ANEC who are positive for influenza are more likely to have hemorrhage and greater thalamic swelling. RANBP2 status was predictive of relapse but not predictive of overall outcome.

Early therapeutic plasma exchange may lead to complete neurological recovery in moderate to severe influenza-associated acute necrotizing encephalopathy

BACKGROUND

Acute necrotizing encephalopathy (ANE) is a pediatric neurological disease, presumably caused by cytokine storms, with a poor prognosis. Immunomodulatory therapy, including therapeutic plasma exchange (TPE), could be an effective treatment.

CASES

Two patients with influenza-associated ANE were treated. The ANE severity scores were 3 and 8 in case 1 (a 3-y-old boy) and case 2 (a 7-y-old boy), respectively. In case 1, intravenous methylprednisolone and TPE were initiated at 8 and 16 h, respectively, after the onset of impaired consciousness. In case 2, multiple organ failure and septic shock persisted even after infusion of fluids and inotropic agents. Intravenous methylprednisolone and TPE were started at 5 and 9 h, respectively, after the onset of impaired consciousness, which improved the inotrope-refractory septic shock. Patient 1 and 2 achieved complete neurological recovery within 4 weeks and after 3 months, respectively. In both patients, cytokine levels were serially measured. There were increased serum interleukin (IL)-6 and IL-10 levels in both patients; patient 1 showed increased IL-6 levels in the initial cerebrospinal fluid sample. There was a post-treatment decrease in serum IL-6 levels in both cases.

DISCUSSION

Early intensive immunomodulatory therapy with TPE may improve neurological outcomes in pediatric influenza-associated ANE. Further studies are required to establish the efficacy of TPE for ANE.

Effect of higher body temperature and acute brain edema on mortality in hemorrhagic shock and encephalopathy syndrome

OBJECTIVE

Hemorrhagic shock and encephalopathy syndrome (HSES) is a severe subtype of acute encephalopathy with a poor prognosis. The factors associated with acute neurological outcomes in patients with HSES remain unclear. This study aimed to determine the clinical features, laboratory and radiological findings, and treatments that determine the acute outcomes of HSES.

METHODS

Forty children with HSES registered in a database of Osaka City General Hospital between 1995 and 2020 were included in this observational study. We retrospectively collected data on clinical features, laboratory and radiological items, and treatments. We divided acute neurological outcomes into two groups: the non-death and death groups in 1 week. Correlations were assessed between these items and acute neurological outcomes.

RESULTS

Twenty-seven and 13 patients comprised the non-death and death groups, respectively. Univariate logistic regression analysis showed that higher body temperature, presence of hemorrhagic episode, elevated lactate level, high glucose level in the cerebrospinal fluid, and brain edema at initial computed tomography (CT) were correlated with the death group. Regarding treatments, barbiturate therapy, intravenous immunoglobulin, and intravenous methylprednisolone were significantly initiated in the non-death group. The multivariate logistic regression model showed higher body temperature (odds ratio [OR], 4.210 [1.409-12.584]; p = 0.010) and brain edema on initial head CT (OR, 46.917 [3.995-550.976]; p = 0.002) were independent factors.

CONCLUSIONS

Higher body temperature and brain edema at the onset of HSES were associated with acute outcomes. The results of this study may be useful for treatment planning and acute outcomes in patients with HSES.

Clinical features and imaging manifestations of acute necrotizing encephalopathy in children

PURPOSE

We summarized the clinical features of acute necrotizing encephalopathy (ANE) in children.

METHODS

Clinical data of 14 children with ANE at one center from January 2017 to January 2020 were retrospectively analyzed. ANE severity score (ANE-ss) was used to assess ANE severity, and the Glasgow Outcome Scale-Extended was used to assess functional outcomes.

RESULTS

Peak incidence was between 1 and 3 years of age (71%), and a large percentage of males were affected (79%). The main manifestations included fever (100%), seizure (86%), and impaired consciousness (100%). Seven patients (58%) developed status epilepticus. The etiology was identified in 10 patients (71%) and mainly included H1N1 (36%) and Epstein-Barr virus (29%).Complications included multiple organ failure (MOF), predominantly liver (36%), heart (21%) and kidney (7%) failure, gastrointestinal hemorrhage (21%), hypernatremia (7%), hematuria (7%), disseminated intravascular coagulation (7%), and shock (7%). Pleocytosis was observed in two patients, and increased cerebrospinal fluid protein was found in 11 patients. A missense mutation in RANBP2 (c.1754C>T: p.Thr585Met) was observed in one patient. Magnetic resonance imaging revealed increased T2 and T1 signal density in multifocal and symmetric brain lesions (bilateral thalami, 100%) in all patients during the acute phase. There were no deaths. Nine children retained neurological sequelae affecting movement, cognition, speech, vision, and/or seizure. Four children recovered almost completely. There was a significant correlation between risk classification and outcome by ANE-ss.

CONCLUSION

ANE is a group of clinical and imaging syndromes. Most patients have severe neurological sequelae, and ANE may have lower mortality. And ANE-ss can assess prognosis.

Influenza A H3N2-Associated Meningoencephalitis in an Older Adult With Viral RNA in Cerebrospinal Fluid: Case Report

Influenza-associated encephalopathy (IAE) is most frequently observed in young children, but less reported in adults. Diagnosis of IAE is difficult, as clinical presentations vary significantly and the influenza virus is rarely detected in cerebrospinal fluid (CSF). Herein, we described the case of an older adult presenting with acute meningoencephalitis due to an influenza A (H3N2) infection and the influenza A (H3N2) RNA is detected in cerebrospinal fluid. To the best of our knowledge, this is infrequently reported in the literature. We emphasize that, in adults presenting with acute viral encephalitis, clinicians should consider an influenza infection as part of the differential diagnosis and that metagenomic next-generation sequencing of CSF for IAE may help establish an accurate diagnosis. It must be emphasized that the administration of steroids in a timely manner following the onset of symptoms may yield a better outcome in patients.

Workshop on RanBP2/Nup358 and acute necrotizing encephalopathy

Dominant missense mutations in RanBP2/Nup358 cause Acute Necrotizing Encephalopathy (ANE), a pediatric disease where seemingly healthy individuals develop a cytokine storm that is restricted to the central nervous system in response to viral infection. Untreated, this condition leads to seizures, coma, long-term neurological damage and a high rate of mortality. The exact mechanism by which RanBP2 mutations contribute to the development of ANE remains elusive. In November 2021, a number of clinicians and basic scientists presented their work on this disease and on the interactions between RanBP2/Nup358, viral infections, the innate immune response and other cellular processes.

Post-Infectious Autoimmunity in the Central (CNS) and Peripheral (PNS) Nervous Systems: An African Perspective

The direct impact and sequelae of infections in children and adults result in significant morbidity and mortality especially when they involve the central (CNS) or peripheral nervous system (PNS). The historical understanding of the pathophysiology has been mostly focused on the direct impact of the various pathogens through neural tissue invasion. However, with the better understanding of neuroimmunology, there is a rapidly growing realization of the contribution of the innate and adaptive host immune responses in the pathogenesis of many CNS and PNS diseases. The balance between the protective and pathologic sequelae of immunity is fragile and can easily be tipped towards harm for the host. The matter of immune privilege and surveillance of the CNS/PNS compartments and the role of the blood-brain barrier (BBB) and blood nerve barrier (BNB) makes this even more complex. Our understanding of the pathogenesis of many post-infectious manifestations of various microbial agents remains elusive, especially in the diverse African setting. Our exploration and better understanding of the neuroimmunology of some of the infectious diseases that we encounter in the continent will go a long way into helping us to improve their management and therefore lessen the burden. Africa is diverse and uniquely poised because of the mix of the classic, well described, autoimmune disease entities and the specifically "tropical" conditions. This review explores the current understanding of some of the para- and post-infectious autoimmune manifestations of CNS and PNS diseases in the African context. We highlight the clinical presentations, diagnosis and treatment of these neurological disorders and underscore the knowledge gaps and perspectives for future research using disease models of conditions that we see in the continent, some of which are not uniquely African and, where relevant, include discussion of the proposed mechanisms underlying pathogen-induced autoimmunity. This review covers the following conditions as models and highlight those in which a relationship with COVID-19 infection has been reported: a) Acute Necrotizing Encephalopathy; b) Measles-associated encephalopathies; c) Human Immunodeficiency Virus (HIV) neuroimmune disorders, and particularly the difficulties associated with classical post-infectious autoimmune disorders such as the Guillain-Barré syndrome in the context of HIV and other infections. Finally, we describe NMDA-R encephalitis, which can be post-HSV encephalitis, summarise other antibody-mediated CNS diseases and describe myasthenia gravis as the classic antibody-mediated disease but with special features in Africa.

Association of O blood type with the prognosis of acute necrotizing encephalopathy in childhood: A single-center cohort study

BACKGROUND

Acute necrotizing encephalopathy (ANE) of childhood is a rare but critical disease with global distribution. Few studies have focused on investigating the relationship between O blood type and the prognosis of ANE.

METHODS

We analyzed retrospectively the data of patients with ANE admitted to the Beijing Children's Hospital from March 2012 to February 2019. Baseline data, clinical characteristics, examination, treatment, and prognosis of O blood group were compared with those of the non-O blood group. Cox regression was used to observe the independent prognostic factors in ANE.

RESULTS

Thirty-one ANE patients were recruited, and 8 (25.8%) of these patients were in the O blood group. The rest (n = 23; 74.2%) were in the non-O blood group. No significant differences were found in the demographic characteristics, clinical features, examinations, and treatments between the two groups (p > 0.05). At 28 days after discharge, the overall survival rate of the O blood group was significantly higher than that of the non-O blood group (χ² = 5.630, p = 0.018). At 1 year after discharge, the survival quality of the O blood group was higher than that of the non-O blood group (p = 0.006). After adjusting for the confounding factors, Cox regression analysis showed that O blood type might be a protective factor in ANE [hazard ratio = 0.283, 95% CI = 0.081-0.988; p = 0.048].

CONCLUSIONS

O blood type may be a protective factor for patients with ANE.