Teaching Neuroimages: COVID-19-Associated Acute Disseminated Encephalomyelitis With Corpus Callosal Hemorrhage

Encephalopathy as a prognostic factor in adults with acute disseminated encephalomyelitis following COVID-19

Numerous reports support the possible occurrence of acute disseminated encephalomyelitis (ADEM) following COVID-19. Herein, we report a case of ADEM in a 53-year-old man 2 weeks after SARS-CoV-2 infection. We reviewed the reports of adult cases of ADEM and its variant acute necrotizing hemorrhagic leukoencephalitis (ANHLE) to check for possible prognostic factors and clinical/epidemiological peculiarities. We performed a descriptive analysis of clinical and cerebrospinal fluid data. Ordinal logistic regressions were performed to check the effect of clinical variables and treatments on ADEM/ANHLE outcomes. We also compared ADEM and ANHLE patients. We identified a total of 20 ADEM (9 females, median age 53.5 years) and 23 ANHLE (11 females, median age 55 years). Encephalopathy was present in 80% of ADEM and 91.3% of ANHLE patients. We found that the absence of encephalopathy predicts a better clinical outcome in ADEM (OR 0.027, 95% CI 0.001–0.611, p = 0.023), also when correcting for the other variables (OR 0.032, 95% CI 0.001–0.995, p = 0.05). Conversely, we identified no significant prognostic factor in ANHLE patients. ANHLE patients showed a trend towards a worse clinical outcome (lower proportion of good/complete recovery, 4.5% vs 16.7%) and higher mortality (36.4% vs 11.1%) as compared to ADEM. Compared to pre-pandemic ADEM, we observed a higher median age of people with post-COVID-19 ADEM and ANHLE, a shorter interval between infection and neurological symptoms, and a worse prognosis both in terms of high morbidity and mortality. Despite being affected by the retrospective nature of the study, these observations provide new insights into ADEM/ANHLE following SARS-CoV-2 infection.

Epidemiology, pathophysiology, and classification of the neurological symptoms of post-COVID-19 syndrome

Introduction

Post-COVID-19 syndrome is a series of chronic signs and symptoms that may appear after SARS-CoV-2 infection, including fatigue, dyspnoea, chest pain, palpitations, anxiety, depression, and joint and muscle pain. The purpose of this study was to review the controversies on post-COVID-19 syndrome, the frequency of neurological symptoms, and the potential pathophysiological mechanisms.

Methods

We present a narrative review of studies published in PubMed since the beginning of the pandemic (January 2020-July 2021).

Results

Patients with history of COVID-19 have been found to present persistent neurological symptoms, including cognitive complaints, memory and concentration problems, headache, anosmia, ageusia, vertigo, and insomnia. Post-COVID-19 syndrome is a heterogeneous disease that lacks a universally accepted definition, which may explain the great variability in the estimated prevalence (2.3%-85%) and symptom duration. The criteria differentiating post-COVID-19 syndrome from chronic fatigue syndrome or critical illness syndrome are ambiguous. Risk factors include older age, female sex, certain comorbidities, and greater number of symptoms in the acute phase. The pathophysiology of the syndrome is largely unknown, although it is probably multifactorial, including immunological mechanisms, neural network dysfunction, neurotransmitter alterations, persistent viral damage, and functional impairment.

Conclusions

Post-COVID-19 syndrome may present after mild or even asymptomatic SARS-CoV-2 infection, causing limitations in activities of daily living and in quality of life. Further research will clarify the origin and most appropriate management of these neurological alterations.

Central neuroinflammation in Covid-19: a systematic review of 182 cases with encephalitis, acute disseminated encephalomyelitis, and necrotizing encephalopathies

Growing evidence demonstrates the association of encephalitis, meningoencephalitis or encephalomyelitis, with SARS-CoV-2 infection. This study aims to determine the profile and possible mechanisms behind CNS inflammatory diseases in the context of Covid-19. We conducted a systematic review of case reports on Covid-19-related encephalitis, meningoencephalitis, acute necrotizing encephalitis, and acute disseminated encephalomyelitis in adults, published before January 2021. A total of 182 cases (encephalitis = 109, meningoencephalitis = 26, acute disseminated encephalomyelitis = 35, acute necrotizing (hemorrhagic) encephalitis = 12) were included. While cerebrospinal fluid (CSF) pleocytosis and increased protein level was present in less than 50%, magnetic resonance imaging (MRI) and electroencephalogram (EEG) were abnormal in 78 and 93.2% of all cases, respectively. Viral particles were detected in cerebrospinal fluid of only 13 patients and autoantibodies were present in seven patients. All patients presented with altered mental status, either in the form of impaired consciousness or psychological/cognitive decline. Seizure, cranial nerve signs, motor, and reflex abnormalities were among associated symptoms. Covid-19-associated encephalitis presents with a distinctive profile requiring thorough diagnosis and thereby a comprehensive knowledge of the disease. The clinical profile of brain inflammation in Covid-19 exhibits majority of abnormal imaging and electroencephalography findings with mild/moderate pleocytosis or proteinorrhachia as prevalent as normal cerebrospinal fluid (CSF). Oligoclonal bands and autoantibody assessments are useful in further evaluating neuro-covid patients, as supported by our pooled evidence. Despite the possibility that direct viral invasion cannot be easily estimated, it is still more likely that immune-mediated or autoimmune reactions play a more important role in SARS-CoV-2 neuroinflammation.

Acute disseminated encephalomyelitis in a patient vaccinated against SARS-CoV-2

Acute disseminated encephalomyelitis (ADEM) is a demyelinating disease, and there are some data that link this event with various vaccinations. We report a young female admitted to the hospital with headache, fever, back pain, nausea, vomiting, and urinary retention. Two weeks prior, she received the first dose of SARS‐CoV‐2 mRNA vaccine. Brain and spinal cord magnetic resonance imaging (MRI) showed distinctive for ADEM widespread demyelinating lesions. The patient was successfully treated with methylprednisolone.

SARS-CoV-2-associated acute disseminated encephalomyelitis: a systematic review of the literature

The literature on cases of acute disseminated encephalomyelitis (ADEM) associated with SARS-CoV-2 infection has been rapidly increasing. However, the specific clinical features of ADEM associated with SARS-CoV-2 (SARS-CoV-2-ADEM) have not been previously evaluated. We screened all articles resulting from a search of PubMed and Web of Science databases looking for reports of ADEM published between December 01, 2019, and June 5, 2021. Of the 48 ADEM cases identified from 37 studies, 34 (71%) had ADEM while 14 (29%) were of AHLE. RT-PCR for SARS-CoV-2 was positive in 83% (n = 19) of patients. 26 patients (54%) were male, and 18 patients (38%) were female, with a male to female sex ratio of 1.4:1; median age was 44 (1.4–71) years. 9 patients (19%, 9/48) were children. Of the 9 children patients, their median age was 9 years (range 1.4–13 years), 6 patients (67%) were female, and 2 patients (22%) were male, with a female to male sex ratio of 3:1.39 patients (81%) was performed CSF analysis. PCR for SARS-CoV-2 tested positive in 3 patients (14%, 3/22) on CSF sample. 31 (64%) of patients had a poor outcome on discharge from hospital. Five (10%) patients died in hospital. Compared to classic ADEM, SARS-CoV-2-ADEM have a more longer duration between the onset of the antecedent infective symptoms and the start of ADEM symptoms, the older age distribution of the patients, relatively poor outcome, a lower full recovery rate, a more frequently brain lesions involved the periventricular white matter and corpus callosum, and less frequently affected the deep gray matter. Taken together, the present comprehensive review reveals that although rare, ADEM can be associated with SARS-CoV-2 infection. SARS-CoV-2-ADEM seems to share most features of classic ADEM, with moderate discrepancies from the classical ADEM.