Incidental Diagnosis of Oligosymptomatic Bilateral Perirenal Erdheim-Chester Disease during Emergency Investigation for COVID-19 Infection.

Erdheim-Chester disease (ECD), a rare form of non-Langerhans histiocytosis, is a multisystem disorder. The case reported here refers to a 49-year-old man presenting at the emergency room with respiratory symptoms. While undergoing diagnostic tests for COVID-19 infection, tomography revealed asymptomatic bilateral perirenal tumors, while renal function remained unaltered.