Epidemiological aspects of olfactory dysfunction.

PURPOSE: This study aimed at assessing the most common aetiological factors causing total or partial olfactory deficit and the statistical analysis of some clinical aspects. MATERIALS AND METHODS: 243 patients reporting alfactory dysfunction were enrolled in this STUDY: A case history was drawn up for each patient, and all of them underwent otolaryngology objective examination, including nasal endoscopy, paranasal sinuses CT-scan, and Utrecht method (GITU) based smell indentification test. RESULTS: Upper respiratory viral infections (40.2%), ceanial-facial traumas (39.3%), and rhinosinusal pathologies (6.3%) were the main aetiopathological factors indentified. A relevant number of case were recorded with unknown aetiology (14.2%). In 2 cases, olfactory dysfunction was due to neurological diseases, in 1 case it was due to intoxication and, in another case, it was congenital. The correlation between aetiology, gender, age, symptoms duration and deficit severity was studied. CONCLUSIONS: many different aetiological factors caused the loss or weakening of the sense of smell. They mainly affected olfactory neurosensorial structures and odorant conduction. However, there were many cases of unknown aetiology. Women, over 40 in particular, were the most affected. Anosmia and severe hyposmia were mainly correlated with traumas and viral pathologies.