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

International consensus definitions for infection-triggered encephalopathy syndromes

AIM

To develop standardized diagnostic criteria for 'infection-triggered encephalopathy syndrome (ITES)' and five specific clinical syndromes of ITES.

METHOD

The draft definitions were based on existing criteria, standardized, and discussed by a panel of international experts using nominal group technique over 18 months to achieve consensus. All criteria use the same format: (1) presence of infection/fever; (2) clinical features including encephalopathy; (3) neuroradiological features on magnetic resonance imaging; (4) exclusion of other causes.

RESULTS

We first highlighted differences between ITES and infectious and autoimmune encephalitis, which is the most important differential diagnosis. Consensus was achieved to define five specific ITESs: acute encephalopathy with biphasic seizures and late reduced diffusion; acute necrotizing encephalopathy; mild encephalopathy with a reversible splenial lesion; acute fulminant cerebral oedema; and acute shock with encephalopathy and multiorgan failure. Two further conditions that are currently classified as epilepsy syndromes but have similar features to ITES, namely febrile infection-related epilepsy syndrome and hemiconvulsion-hemiplegia-epilepsy syndrome, are also discussed.

INTERPRETATION

The consensus definition is expected to improve awareness of this disease concept, provide diagnostic framework, and facilitate future international research and clinical trials.

Acute necrotizing encephalopathy infected with the SARS-CoV-2 in children: Case series and literature review of clinical outcomes with the use of Tocilizumab

BACKGROUND AND OBJECTIVE

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes acute necrotizing encephalopathy (ANE), which has a high mortality rate and severe sequelae. This study aimed to identify ANE early and evaluate the usefulness of tocilizumab in ANE treatment.

METHODS

We retrospectively included eight paeefediatric ANE cases infected with SARS-CoV-2 at Xi'an Children's Hospital, China, from December 1, 2022 to May 1, 2023. A literature search was performed using the PUBMED, SPRING, SCOPUS, and EMBASE databases. This study included eleven patients. Clinical characteristics, laboratory test results, imaging features, and treatment options were analysed.

RESULTS

Eight of the 19 cases (42 %) died, one (5 %) recovered, and nine (47 %) improved with residual neurological dysfunction. Eighteen patients presented with fever, with 56 % having ≥40 °C. Twelve patients (63 %) presented with dysfunction consciousness. Eight (42 %) patients experienced frequent convulsions. All eight patients in our hospital had elevated procalcitonin levels (mean: 21.32 ng/mL, range: 0.10-89.40 ng/mL). Alanine aminotransferase levels were elevated (mean: 632.81 U/L, range: 13.00-2251.00 U/L) in six patients. Seven patients showed elevated uric acid levels(mean: 396.50 μmol/L, range: 157.00-660.00 μmol/L). Brain imaging indicated that all the patients had symmetrical injuries to the bilateral thalami, accompanied by symmetrical injuries in the cerebrum, cerebellum, basal ganglia, and brain stem. Compared with the classical treatment (n = 9), the combination with tocilizumab (n = 6) showed a statistically difference in mortality (p = 0.028 < 0.05).

CONCLUSION

The typical clinical manifestations of ANE in children with SARS-CoV-2 infection are acute onset with high fever, frequent convulsions and rapidly worsening disturbance of consciousness. Tocilizumab treatment could reduces mortality in ANE.

COVID-19 susceptibility, hospitalization and severity and the risk of brain cortical structure: a Mendelian randomization study

BACKGROUND

Observational studies have reported structural changes in the brains of patients with coronavirus disease 2019 (COVID-19); it remains unclear whether these associations are causal.

AIM

We evaluated the causal effects of COVID-19 susceptibility, hospitalization and severity on cortical structures.

DESIGN

Mendelian randomization (MR) study.

METHODS

Data on the different COVID-19 phenotypes were obtained from the latest large-scale genome-wide association study (R7) of the COVID-19 Host Genetics Initiative. Brain structure data, including cortical thickness (TH) and surface area (SA), were obtained from the ENIGMA Consortium. Additionally, we employed the round 5 dataset released in January 2021 as the validation cohort. The inverse-variance weighted (IVW) method was used as the primary analysis in MR. Sensitivity analyses were conducted to evaluate heterogeneity and pleiotropy. We performed enrichment analysis on the MR analyses that passed the sensitivity analysis filtering.

RESULTS

After IVW and sensitivity analyses, we observed causal associations between COVID-19 susceptibility and rostral middle frontal SAw (P = 0.0308, β = -39.1236), cuneus THw (P = 0.0170, β = -0.0121), medial orbitofrontal THw (P = 0.0002, β = 0.0225), postcentral THw (P = 0.0217, β = -0.0106), temporal pole THw (P = 0.0077, β = 0.0359), medial orbitofrontal SAnw (P = 0.0106, β = -24.0397), medial orbitofrontal THnw (P = 0.0007, β = 0.0232), paracentral SAnw (P = 0.0483, β = -20.1442), rostral middle frontal SAnw (P = 0.0368, β = -81.9719) and temporal pole THnw (P = 0.0429, β = 0.0353). COVID-19 hospitalization had causal effects on medial orbitofrontal THw (P = 0.0053, β = 0.0063), postcentral THw (P = 0.0143, β = -0.0042), entorhinal THnw (P = 0.0142, β = 0.0142), medial orbitofrontal THnw (P = 0.0147, β = 0.0065) and paracentral SAnw (P = 0.0119, β = -7.9970). COVID-19 severity had causal effects on rostral middle frontal SAw (P = 0.0122, β = -11.8296), medial orbitofrontal THw (P = 0.0155, β = 0.0038), superior parietal THw (P = 0.0291, β = -0.0021), lingual SAnw (P = 0.0202, β = -11.5270), medial orbitofrontal THnw (P = 0.0290, β = 0.0039), paracentral SAnw (P = 0.0180, β = -5.7744) and pars triangularis SAnw (P = 0.0151, β = -5.4520).

CONCLUSION

Our MR results demonstrate a causal relationship between different COVID-19 phenotypes and cortical structures.

Mild Neurological Manifestations Associated With Severe Acute Respiratory Syndrome Coronavirus 2 Infection in Hospitalized Children During the Omicron Wave in Singapore: A Retrospective Cohort Review

BACKGROUND

Neurological complications with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron variant have been reported in adults; however, there are little data in the pediatric population. We aimed to report on the prevalence and clinical characteristics of children with neurological symptoms during the SARS-CoV-2 omicron wave.

METHODS

This was a single-center, retrospective cohort review of children (<18 years old) hospitalized for SARS-CoV-2 infection from December 2, 2021, to June 30, 2022.

RESULTS

During the study period, 455 children (mean age 4.8 years, range 0.67 to 18, male 58.9%) were hospitalized with SARS-CoV-2 infection. A total of 108 (23.7%) children experienced neurological symptoms; most common were seizures (62.0%), headaches (32.4%) and giddiness (14.8%). Seizures included febrile seizures (64.1%), acute symptomatic seizures (17.9%), and breakthrough seizures in known epileptics (17.9%). Children with neurological manifestations were older (7.3 vs 4.0 years, P < 0.00001), more likely to have underlying epilepsy (9.3% vs 1.2%, P = 0.0002) or neurodevelopmental disorders (17.6% vs 1.7%, P < 0.00001), and presented earlier in their illness (2.1 vs 2.8 days, P < 0.00001), compared with those without neurological manifestations. Neurological symptoms fully resolved in all but one patient at discharge. There were no mortalities and no difference in duration of hospitalization (3.1 vs 3.7 days, P = 0.5) between the groups.

CONCLUSIONS

One in four hospitalized children with SARS-CoV-2 infection when omicron variant was dominant experienced mild neurological symptoms. Overall risk factors for neurological symptoms associated with SARS-CoV-2 included older age, pre-existing febrile seizures/epilepsy and neurodevelopmental disorders.

Defining the Clinicoradiologic Syndrome of SARS-CoV-2 Acute Necrotizing Encephalopathy: A Systematic Review and 3 New Pediatric Cases

BACKGROUND AND OBJECTIVES

We characterize clinical and neuroimaging features of SARS-CoV-2-related acute necrotizing encephalopathy (ANE).

METHODS

Systematic review of English language publications in PubMed and reference lists between January 1, 2020, and June 30, 2023, in accordance with PRISMA guidelines. Patients with SARS-CoV-2 infection who fulfilled diagnostic criteria for sporadic and genetic ANE were included.

RESULTS

From 899 articles, 20 cases (17 single case reports and 3 additional cases) were curated for review (50% female; 8 were children). Associated COVID-19 illnesses were febrile upper respiratory tract infections in children while adults had pneumonia (45.6%) and myocarditis (8.2%). Children had early neurologic deterioration (median day 2 in children vs day 4 in adults), seizures (5 (62.5%) children vs 3 of 9 (33.3%) adults), and motor abnormalities (6 of 7 (85.7%) children vs 3 of 7 (42.9%) adults). Eight of 12 (66.7%) adults and 4 (50.0%) children had high-risk ANE scores. Five (62.5%) children and 12 (66.7%) adults had brain lesions bilaterally and symmetrically in the putamina, external capsules, insula cortex, or medial temporal lobes, in addition to typical thalamic lesions of ANE. Hypotension was only seen in adults (30%). Hematologic derangements were common: lymphopenia (66.7%), coagulopathy (60.0%), or elevated D-dimers (100%), C-reactive protein (91.7%), and ferritin (62.5%). A pathogenic heterozygous c/.1754 C>T variant in RANBP2 was present in 2 children: one known to have this before SARS-CoV-2 infection, and a patient tested because the SARS-CoV-2 infection was the second encephalopathic illness. Three other children with no prior encephalopathy or family history of encephalopathy were negative for this variant. Fifteen (75%) received immunotherapy (with IV methylprednisolone, immunoglobulins, tocilizumab, or plasma exchange): 6 (40.0%) with monotherapy and 9 (60.0%) had combination therapy. Deaths were in 8 of 17 with data (47.1%): a 2-month-old male infant and 7 adults (87.5%) of median age 56 years (33-70 years), 4 of whom did not receive immunotherapy.

DISCUSSION

Children and adults with SARS-CoV-2 ANE have similar clinical features and neuroimaging characteristics. Mortality is high, predominantly in patients not receiving immunotherapy and at the extremes of age.

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.

The youngest infant with COVID-19-associated necrotizing encephalitis in Asia: A case report

Acute necrotic encephalopathy in children is a very rare complication of severe acute respiratory syndrome coronavirus 2 infection and has rarely been reported worldwide. A 45-day-old girl was admitted to our hospital with fever and listlessness. A nose swab tested positive for the novel coronavirus nucleic acid, and her cerebrospinal fluid was positive for severe acute respiratory syndrome coronavirus 2. An early head magnetic resonance imaging scan indicated multiple abnormal signals in her bilateral cerebral hemispheres, and encephalitis was diagnosed. Twenty-three days after hospitalization, bilateral cerebral atrophy-like changes were observed on magnetic resonance imaging, with multiple softening lesions in the bilateral cerebral hemispheres, accompanied by convulsions. She was admitted to the hospital for mechanically assisted ventilation, and her condition improved after treatment of her symptoms with antiepileptic medication, anti-infection drugs, glucocorticoids, and immunoglobulins. Acute necrotic encephalopathy associated with severe acute respiratory syndrome coronavirus 2 infection in children should be detected and treated as early as possible. Satisfactory short-term efficacy can be obtained, but long-term neurological sequelae often linger.

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.

Association of IL6 and IL10 gene promotor polymorphisms with susceptibility to acute necrotizing encephalopathy

Objective

Acute necrotizing encephalopathy (ANE) is a severe complication of infectious diseases affecting the brain and systemic organs. The main pathogenesis is cytokine storm, in which interleukin-6 (IL-6) and interleukin-10 (IL-10) are candidates for key cytokines. To further elucidate their roles in the etiology and pathogenesis of ANE, we studied polymorphisms in the promotor regions of the IL6 and IL10 genes by genetic and functional analyses.

Methods

We first conducted a case-control association study of four IL6 and three IL10 polymorphisms. We genotyped 31 Japanese ANE cases and compared the results with those of approximately 200 Japanese controls. For the two polymorphisms showing a possible association, we next studied whether the polymorphisms alter the production of IL-6 or IL-10 by lymphoblasts upon phorbol 12-myristate 13-acetate (PMA) stimulation.

Results

The frequencies of IL6 rs1800796G allele and IL10 rs1800871/rs1800872 CC/CC diplotype were significantly higher in ANE cases than in controls. The IL10 CC/CC diplotype was associated with low IL-10 production, whereas the IL6 GG genotype was not associated with IL-6 production.

Conclusion

IL10 rs1800871/rs1800872 CC/CC diplotype may predispose Japanese children to ANE by altering IL-10 production in the early phase of infection. Etio-pathogenetic significance of IL6 rs1800796G remains to be elucidated.

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.

Neurological consequences of SARS-CoV-2 infections in the pediatric population

COVID-19 in the pediatric population is mostly asymptomatic. However, 1 out of 5 children presents non-specific neurologic symptoms such as headache, weakness, or myalgia. Furthermore, rarer forms of neurological diseases are increasingly being described in association to a SARS-CoV-2 infection. Encephalitis, stroke, cranial nerves impairment, Guillain-Barré syndrome or acute transverse myelitis have been reported and account for around 1% of pediatric COVID-19 cases. Some of these pathologies may occur during or after the SARS-CoV-2 infection. The pathophysiological mechanisms range from direct invasion of the central nervous system (CNS) by SARS-CoV-2 itself to postinfectious immune-mediated CNS inflammation. In most cases, patients presenting neurological pathologies related to SARS-CoV-2 infection are at greater risk of life-threatening complications and should be closely monitored. Further studies are needed to acknowledge the potential long-term neurodevelopmental consequences of the infection.