A Rare Case of Invasive Central Nervous System Aspergillus niger in a Previously Immunocompetent Patient After Corticosteroid Treatment for COVID-19.

Aspergillus is a ubiquitous saprophyte found in air, soil, and organic matter. Humans inhale the spore form of the fungus, but manifestations of the disease are typically predominantly seen in immunocompromised patients. Invasive central nervous system (CNS) aspergillosis is even more uncommon, and epidemiological data is sparse, particularly in immunocompetent patients. We report the case of a 67-year-old previously immunocompetent female with no known comorbidities who was treated with corticosteroids for COVID-19 one month prior to admission for altered mental status (AMS). Subsequent imaging and biopsy demonstrated invasive CNS Aspergillus niger. Though a rare cause of AMS in immunocompetent patients, this report draws attention to the detrimental immunosuppressive effects of corticosteroid therapy in COVID-19.