ear, nose, and throat disorders
Anosmia
Pathophysiology of Anosmia
Anosmia occurs when Intranasal swelling or other obstruction prevents odors from gaining access to the olfactory area. The olfactory neuroepithelium is destroyed. The olfactory nerve fila, bulbs, tracts, or central connections are destroyed (see table). Major causes of anosmia include Traumatic Brain Injury (TBI) (young adults) Introduction to Brain Infections None Alzheimer Disease (older adults) Prior upper respiratory infection (URI), especially influenza, is implicated in 14 to 26% of all patients that present with hyposmia or anosmia. Medications can contribute to anosmia in susceptible patients. Other causes include prior head and neck radiation, recent nasal or sinus surgery, nasal and brain tumors, and toxins. The role of tobacco is uncertain. Anosmia may be an early symptom and thus a clue to COVID-19 , caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Immediately urge patients who are at risk of COVID-19 and have suddenly lost their sense of smell to isolate themselves from others. 