Case Report: Acute Necrotizing Encephalopathy Following COVID-19 Vaccine

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.

Pediatric recurrent acute necrotizing encephalomyelitis, RANBP2 genotype and Sars-CoV-2 infection: Diagnosis, pathogenesis and targeted treatments from a case study

Acute necrotizing encephalopathy (ANE) is a rare disease not yet described in children with Covid-19. RANBP2 gene variations are implicated in recurrences in the genetic form of ANE, the so called ANE1. We report the first case of pediatric ANE1 following Sars-CoV-2 infection. She had a first episode at 2 years of age following influenza type A with full recovery, many other respiratory and non-respiratory febrile viral infections without recurrences and a severe recurrence following Sars-CoV-2 infection, suggesting a potentiation effect on cytokine cascade. Her MRI showed the typical pattern of injury resembling that of mitochondrial disorders, and supported the role of RANBP2 in mitochondrial homeostasis. This case rises attention on diagnostic challenges and offers several interesting tips for discussion about new perspectives in pathogenesis and targeted treatments.

A review of the potential neurological adverse events of COVID-19 vaccines

Despite the advantages of getting access to the coronavirus disease 2019 (COVID-19) vaccines, their potential ability to induce severe adverse events (AEs) has been a significant concern. Neurological complications are significant among the various adverse events following immunization (AEFI) due to their likely durability and debilitating sequelae. Neurological AEs following COVID-19 vaccination can either exacerbate or induce new-onset neuro-immunologic diseases, such as myasthenia gravis (MG) and Guillain-Barre syndrome (GBS). The more severe spectrum of AEs post-COVID19 vaccines has included seizures, reactivation of the varicella-zoster virus, strokes, GBS, Bell's palsy, transverse myelitis (TM), and acute disseminated encephalomyelitis (ADEM). Here, we discuss each of these neurological adverse effects separately.

Neurological Complications Following COVID-19 Vaccination

PURPOSE OF REVIEW

A variety of neurological complications have been reported following the widespread use of the COVID-19 vaccines which may lead to vaccine hesitancy and serve as a major barrier to the public health aim of achieving protective herd immunity by vaccination. In this article, we review the available evidence regarding these neurological adverse events reported, to provide clarity regarding the same so that unfounded fears maybe put to rest.

RECENT FINDINGS

There is a greater than expected occurrence of severe neurological adverse events such as cortical sinus venous thrombosis, Bell's palsy, transverse myelitis, and Guillain-Barré syndromes along with other common effects such as headaches following different kinds of COVID-19 vaccination. Precipitation of new onset demyelinating brain lesions with or without detection of specific antibodies and worsening of pre-existing neurological disorders (like epilepsy, multiple sclerosis) are also a matter of great concern though no conclusive evidence implicating the vaccines is available as of now. The COVID-19 pandemic is far from being over. Till such time that a truly effective anti-viral drug is discovered, or an appropriate therapeutic strategy is developed, COVID-appropriate behavior and highly effective mass vaccination remain the only weapons in our armamentarium to fight this deadly disease. As often occurs with most therapeutic means for the treatment and prevention of any disease, vaccination against COVID-19 has its hazards. These range from the most trivial ones like fever, local pain and myalgias to several potentially serious cardiac and neurological complications. The latter group includes conditions like cerebral venous thrombosis (curiously often with thrombocytopenia), transverse myelitis and acute inflammatory demyelinating polyneuropathy amongst others. Fortunately, the number of reported patients with any of these serious complications is far too low for the total number of people vaccinated. Hence, the current evidence suggests that the benefits of vaccination far outweigh the risk of these events in majority of the patients. As of now, available evidence also does not recommend withholding vaccination in patients with pre-existing neurological disorders like epilepsy and MS, though adenoviral vaccines should be avoided in those with history of thrombotic events.

The Clinical Neurophysiology of COVID-19- Direct Infection, Long-Term Sequelae and Para-Immunization responses: A literature review

The COVID-19 pandemic resulting from the SARS-CoV-2 virus is in its third year. There is continuously evolving information regarding its pathophysiology and its effects on the nervous system. Clinical neurophysiology techniques are commonly employed to assess for neuroanatomical localization and/or defining the spectrum of neurological illness. There is an evolving body of literature delineating the effects of the SARS-CoV-2 virus on the nervous system as well as para-immunization responses to vaccination against this virus. This review focuses on the use of neurophysiological diagnostic modalities in the evaluation of potential acute and long-term neurological complications in patients that experience direct infection with SARS-CoV-2 and analyzes those reports of para-immunization responses to vaccination against the SARS-CoV-2 virus. The neurophysiological modalities to be discussed include electroencephalography (EEG), evoked potentials (EPs), nerve conduction studies and electromyography (EMG/NCV), autonomic function tests, transcranial magnetic stimulation (TMS) and Transcranial Doppler ultrasound (TCD).