Clinical, neurophysiological and neuroradiological characteristics of 30 cases of SARS-COV-2-associated encephalitis in Lombardia

ABSTRACT

Background and aims: The number of cases of encephalitis in COVID-19 pandemic is increasing. We describe characteristics and outcome of encephalitis in COVID-19 (COV-ENC) patients in one of the most affected regions by COVID-19 of the world, Lombardia, during the first pandemic wave. Methods: A multi-center observational study on neurological complications in COVID-19 patients was conducted by the Italian society of Hospital Neuroscience (SNO). Adult patients admitted to 20 Neurological Departments in Lombardia between February-April 2020 with COV-ENC have been included. Results: 30 COV-ENC patients had a mean age of 66.5 years and male frequency of 56.6%. Altered consciousness was characterized by confusion in 86%, coma in 30%, delirium in 37.9% and alteration of personality traits in 27.6%. Epileptic seizures occurred in 74% of cases. One third of cases had hyperproteinorrachia, one third pleocytosis/hyperproteinorrachia, and remaining third had a normal CSF. PCR for SARS-CoV-2 was negative in all tested patients. EEG was altered in 82.7% of patients. Brain CT and MRI were normal in 9 patients, and among abnormal findings 9 patients had mesial temporal lesions, one of which confirmed with PET imaging. The course was favorable in 39.2% of patients, sequelae were few in 26.6% and moderate in 19.2%, while 20% of patients died. Conclusions: The outcome tends to be worse in male patients. PCR negativity seems to confirm an autoimmune etiology more than a direct invasion of the virus. However, a temporal lobe involvement, detected in 30% of patients with COV-ENC, suggests usual sites of encephalitis due to herpes virus.