ABSTRACT
To investigate the relationship between infection, water exposure, trauma and allergy and the development of otitis externa. This study included 100 patients with acute external otitis and 200 participants as a control group, matched in age and sex. All patients were asked about the frequency of different social habits and presence or absence of any allergic disorder. Otoscopy and microbiological analysis were carried out. It was found that 55% of cases revealed positive microbiological analysis. There was no apparent difference between the two groups regarding frequency of swimming, showering and hair washing. Allergic disorders were nearly four times more common in the otitis externa group, suggesting possible immunological etiology. A significant difference was found between the two groups regarding the use of agents capable of traumatizing the external canal. Eczematous otitis externa and viral causes accounted for 45% of the cases. Conclusions: Trauma to the external canal was proven to be statistically significant in the development of otitis externa. Allergic and viral causes also play an important role