Hemphagocytic Lymphohistiocytosis Secondary to COVID-19: A Case Report

Hemophagocytic lymphohistiocytosis (HLH) is categorized into primary HLH and secondary HLH. Primary or familial HLH is an autosomal recessive disorder due to mutation in immune regulatory genes. Secondary HLH is an uncommon hyperinflammatory disease triggered by a critical illness (malignancies or viral infection) that induces an uncontrollable excessive immune response, which results in multiorgan failure. Due to the rarity of the syndrome, HLH is associated with worse outcomes. Severe coronavirus disease-19 (COVID-19) is identified as a trigger of HLH, and published literature suggests that patients with severe COVID-19 are at high risk of developing HLH. COVID-19-associated HLH is rarely reported in the literature. Herein we present a case of secondary HLH due to COVID-19 presented in the emergency department with prolonged non-resolving fever.