Acute necrotizing encephalopathy: an underrecognized clinicoradiologic disorder

Genomics and Radiogenomics in Inherited Neurometabolic Disorders - A Practical Primer for Pediatricians

Advances in genetics has revolutionised the way we understand, diagnose and manage neurological disorders. Notwithstanding the fact that genetic confirmation has already become standard of care in routine clinical practice, radiological and clinical phenotyping has not diminished in value; in fact it has found an enhanced role in guiding and interpreting genetic test results. Inherited neurometabolic disorders are a prominent group of disorders which are seen commonly in clinical practice and many are potentially treatable. The concept of Radiogenomics is the bridge from phenotype to genotype and the strength of association varies widely across different inherited metabolic diseases. Understanding the strengths and limitations of these correlations forms the basis of success of multidisciplinary approach to diagnose these disorders. In this article authors give a brief overview of the genetic basis of a disease, available genetic tests and the prominent role of radiology in contemplating a diagnostic suspicion and guiding further confirmatory tests.

Puzzling mRNA: Alternative splicing fine-tunes specificity and function

In this issue of the Biomedical Journal we discover how alternative splicing might modulate the cell-type specificity and exact function of a ubiquitous purinergic receptor and how the beta blocker propanolol can contribute to breast cancer therapy. Moreover, we learn which culture conditions generate the best vascularisation of tissue engineered bone and which are the clinical features of acute necrotising encephalopathy in adults. Other studies reveal, how laser irradiation can fix fractured all-ceramic dental restorations in situ, and finally that nuclear magnetic resonance holds great potential for the rapid detection of pathogens.

Acute Necrotizing Encephalopathy in Children: a Long Way to Go

BACKGROUND

Acute necrotizing encephalopathy (ANE) is a rare, but potentially life threatening neurological condition in children. This study aimed to investigate its clinical spectrum, diagnostic and therapeutic dilemma, and prognosis.

METHODS

Twelve children with ANE were included in the study. The diagnosis was made by clinical and radiological characteristics from January 1999 to December 2017 and their clinical data were retrospectively analyzed.

RESULTS

A total of 12 children aged 6 to 93 months at onset (5 male: 7 female) were evaluated. The etiology was found in 4 of them (influenza A, H1N1; coxsackie A 16; herpes simplex virus; and RANBP2 gene/mycoplasma). The most common initial presentations were seizures (67%) and altered mental status (58%). The majority of the subjects showed elevation of aspartate aminotransferase/alanine aminotransferase with normal ammonia and increased cerebrospinal fluid protein without pleocytosis. Magnetic resonance imaging revealed increased T2 signal density in bilateral thalami in all patients, but the majority of the subjects (67%) also had lesions in other areas including tegmentum and white matter. Despite the aggressive immunomodulatory treatments, the long-term outcome was variable. One child and two sisters with genetic predisposition passed away.

CONCLUSION

ANE is a distinctive type of acute encephalopathy with diverse clinical spectrum. Even though the diagnostic criteria are available, they might not be watertight. In addition, treatment options are still limited. Further studies for better outcome are needed.

Developing a mouse model of acute encephalopathy using low-dose lipopolysaccharide injection and hyperthermia treatment

IMPACT STATEMENT

Acute encephalopathy (AE), mainly reported in East Asia, is classified into four categories based on clinical and neuropathological findings. Among them, AE caused by cytokine storm is known as the severest clinical entity that causes cerebral edema with poor prognosis. Because suitable and convenient model animal of AE had not been developed, the treatment of patients with AE is not established. In the present study, we established a simple and convenient protocol to mimic AE due to cytokine storm. Our model animal should be useful to elucidate the pathogenesis of AE.

Varying Patterns of CNS Imaging in Influenza A Encephalopathy in Childhood

PURPOSE

The brain imaging findings in children with neurological complications associated with influenza A infections are presented and analyzed and pathological imaging changes including atypical intracerebral hemorrhages in these patients are discussed.

METHODS

Neuroimaging findings in six children with influenza encephalopathy following influenza A infection between 2012-2017 were retrospectively investigated. Of these five underwent magnetic resonance imaging (MRI) and one computed tomography (CT). Gene analysis was performed in two cases with acute necrotizing encephalitis of childhood (ANEC).

RESULTS

The MRI findings of one child were concordant with mild encephalopathy with a reversible splenial lesion (MERS); this patient recovered but remained aphasic. In two cases MRI showed typical bilateral thalamic lesions as a feature of ANEC; genetic testing facilitated the diagnosis in one case. One of the patients died, the other showed little improvement. The remaining three patients had multiple diffuse cerebral hemorrhages predominantly affecting the supratentorial white matter after influenza A infection complicated by pneumonia, rhabdomyolysis and sepsis requiring extracorporeal membrane oxygenation (ECMO).

CONCLUSION

Neurological complications in children associated with influenza A infection may include MERS and ANEC. Additionally, atypical disseminated intracerebral hemorrhages as a complication of influenza A infection is reported.

Moonlighting nuclear pore proteins: tissue-specific nucleoporin function in health and disease

The nuclear pore complex is the main transportation hub for exchange between the cytoplasm and the nucleus. It is built from nucleoporins that form distinct subcomplexes to establish this huge protein complex in the nuclear envelope. Malfunctioning of nucleoporins is well known in human malignancies, such as gene fusions of NUP214 and NUP98 in hematological neoplasms and overexpression of NUP88 in a variety of human cancers. In the past decade, the incremental utilization of next-generation sequencing has unraveled mutations in nucleoporin genes in the context of an increasing number of hereditary diseases, often in a tissue-specific manner. It emerges that, on one hand, the central nervous system and the heart are particularly sensitive to mutations in nucleoporin genes. On the other hand, nucleoporins forming the scaffold structure of the nuclear pore complex are eminently mutation-prone. These novel and exciting associations between nucleoporins and human diseases emphasize the need to shed light on these unanticipated tissue-specific roles of nucleoporins that may go well beyond their role in nucleocytoplasmic transport. In this review, the current insights into altered nucleoporin function associated with human hereditary disorders will be discussed.

Acute necrotizing encephalopathy in an adult with influenza A infection

Acute necrotizing encephalopathy following influenza infection is a rapidly progressing disease with high morbidity. Although the neurological disorder is sometimes reported in children, it is very rare in adults. We herein describe an adult with acute necrotizing encephalopathy captured on a series of brain magnetic resonance images. A 55-year-old man had fever and impaired consciousness. He was diagnosed with influenza A (H1N1). Brain magnetic resonance imaging revealed symmetrical lesions in the cerebellum and basal nucleus, showing typical acute necrotizing encephalopathy. Physicians should know that influenza-associated acute necrotizing encephalopathy can occur even in middle-aged adults.

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

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

RANBP2 mutation in an Indian child with recurrent acute necrotizing encephalopathy

BACKGROUND

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

DESCRIPTION OF THE CASE

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

CONCLUSIONS

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

Atypical Presentations of Respiratory Syncytial Virus Infection: Case Series

The respiratory syncytial virus (RSV) usually causes a lower respiratory tract infection in affected patients. RSV has also been infrequently linked to extrapulmonary diseases in children. We report four children who had unusually severe clinical manifestations of RSV infections requiring critical care admission. These patients presented to the Royal Hospital, Muscat, Oman, in December 2013 with acute necrotising encephalopathy (ANE), acute fulminant hepatic failure with encephalopathy, pneumatoceles and croup. A unique presentation of ANE has not previously been reported in association with an RSV infection. All patients had a positive outcome and recovered fully with supportive management.

Acute necrotising encephalopathy in a child with H1N1 influenza infection: a clinicoradiological diagnosis and follow-up

Acute necrotising encephalopathy of childhood (ANEC) is a fulminant disorder with rapid progressive encephalopathy, seizures and poor outcome. It has been reported in association with various viral infections. We describe the clinicoradiological findings and short-term follow-up in a child with H1N1 influenza-associated ANEC. Laminar, target or tricolour pattern of involvement of the thalami was seen on apparent diffusion coefficient images. Our patient had significant morbidity at discharge despite early diagnosis and management with oseltamivir and immunoglobulin. Repeat imaging after 3 months had shown significant resolution of thalamic swelling, but there was persistence of cytotoxic oedema involving bilateral thalami. She was pulsed with intravenous steroids and maintained on a tapering schedule of oral steroids. This report emphasises the need for a high index of suspicion to establish early diagnosis, promotion of widespread immunisation strategies to prevent influenza outbreak, and more research to establish standard treatment protocols for this under-recognised entity.