Encephalopathy in patients with COVID‐19: A review

Abstract

Encephalopathy and encephalitis are major and devastating severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus-associated central nervous system complications. Hypoxic/metabolic changes produced by intense inflammatory response against the virus triggers cytokine storm and subsequently acute respiratory distress syndrome and multiple organ failure. Hypoxic/metabolic changes result in encephalopathy. The presence of comorbidities predisposes to hypoxic/metabolic changes responsible for encephalopathy. Altered consciousness, ranging from mild confusion, delirium, to deep coma, is hallmark clinical features. Cortical and subcortical T2/FLAIR signal changes are common neuroimaging abnormalities. In a few isolated case reports of SARS-CoV-2 encephalitis, the virus has been demonstrated in cerebrospinal fluid. The presence of anosmia and ageusia can help in differentiation from other encephalopathies. We analyzed published reports on coronavirus disease 2019-associated encephalopathy. Encephalopathy is common in older patients, the majority are more than 50 years of age. The patients having encephalopathy/encephalitis are either severely or critically ill. Many patients were already on mechanical ventilation. Lung abnormalities are noted in almost all of the patients, presenting with encephalopathy. Encephalopathy is always preceded by commoner clinical features, like, fever, cough, dyspnoea, and headache. In majority, patients are already in the intensive care unit, when encephalopathy develops.

Cerebrospinal fluid findings in neurological diseases associated with COVID-19 and insights into mechanisms of disease development

“…In our study, encephalopathy was more frequent among the elderly and men. In a recent review, encephalopathy in COVID-19 was shown to be more common among individuals with more than 50 years of age ( Garg et al 2020 ), which corroborates our data.…”

“…As of July 31, 2020, more than 17 million cases of COVID-19 were confirmed worldwide ( Dong et al 2020 ). Hence, the spectrum of neurological diseases associated with SARS-CoV-2 infection is expanding, including ADEM ( Parsons et al, 2020 , Zanin et al, 2020 ), meningoencephalitis ( Bernard-Valnet et al, 2020 , Dogan et al, 2020 , Moriguchi et al, 2020 ), encephalitis ( Pilotto et al, 2020 , Ye et al, 2020 ), GBS ( Alberti et al, 2020 , Coen et al, 2020 , Juliao Caamaño and Alonso Beato, 2020 , Ottaviani et al, 2020 , Toscano et al, 2020 , Zhao et al, 2020 ), and encephalopathies ( Garg et al 2020 ). However, the conduction of clinical studies including CSF sampling and the collection of detailed clinical and laboratory data in the setting of COVID-19 pandemic has been challenging.…”

Electroencephalographic findings in COVID-19 patients: A systematic review

“…A wide range of etiologies may lead to diffuse background slowing such as sedative and anesthetic effect, various etiologies of encephalopathy, and central nervous system infectious processes. COVID-19-associated encephalopathy was found to be encountered in older and critically ill patients and may be of hypoxic-ischemic, toxic-metabolic, and inflammatory origin [ 38 ]. It remains uncertain whether the neurologic complications of COVID-19 such as encephalopathy is due to direct viral neuroinvasion or is a result of the critical illness.…”

COVID-19 Triage and Test Center: Safety, Feasibility, and Outcomes of Low-Threshold Testing

“…Analysis of clinical predictors showed that it is virtually impossible to include or exclude COVID-19 on clinical grounds only. Even though certain markers defining influenza-like illness, such as fever, myalgia, chills, and cough, were somewhat predictive of positive swab results in our setting, nonspecific symptoms, such as weakness and confusion [ 16 ] were similarly predictive. Although we previously demonstrated that nonspecific symptoms such as weakness are associated with unfavorable prognosis [ 17 ], these symptoms do not generally increase the probability of infection in (older) adults in the ED [ 18 , 19 ].…”