Eastern Equine Encephalitis

Abstract

Purpose of ReviewTo describe the clinical presentation, diagnosis, management, and outcomes of 4 confirmed Eastern equine encephalitis (EEE) cases and a review of the literature.Recent FindingsThere was a sharp rise in the number of EEE cases in the United States in 2019, with 38 confirmed cases and 15 deaths. Our institution cared for 10% of patients with neuroinvasive EEE nationwide. These were the first cases seen locally since 2010.SummaryEEE virus causes one of the most lethal types of arboviral encephalitis in the United States with a mortality of 30%–40%. Manifestations of EEE infections can range from mild encephalopathy to coma. Common findings include CSF pleocytosis and involvement of the basal ganglia on MRI. Given the rarity of this disease and nonspecific findings, diagnosis can be challenging, and a high clinical suspicion is important. Management is mainly supportive, and the use of IV immunoglobulin remains controversial. Two of our 4 patients died; these patients had coma within 48 hours, hyponatremia, involvement of bilateral thalami and brainstem, status epilepticus, and severe brain dysfunction in EEG.