AB190. SOH24AB_115. Seven degrees of separation in otitis externa

Background: Successful treatment of recurrent otitis externa is related to breaking the itch/infection cycle. It is suggested that it should be considered primarily a skin complaint in a tube leading to the ear. Effective management techniques have been more dermatological than truly otological. The local preventative Do-NOT strategy is advice that patients should obey the Granny elbow rule by not putting anything smaller than the elbow into the ear and maintenance therapy with nizoral (N) to prevent itch, insufflation of ototopical powder (O) to the canal and tacrolimus (T) for itch. A new classification system is proposed to consider the degree of inflammation and infection but include complications. Methods: A narrative review was performed with the intention of formulating a clinically applicable classification of the degrees of inflammation in otitis externa using sequential clinical imaging as a support. Results: Otitis externa ranges from normal canals with itch or pre-pain to inflammatory non-infective (negative growth on ear swab) or infective (proven on microbiology culture), non-oedematous or oedematous auditory meatuses. Complications include perichondritis, facial cellulitis, and both typical or atypical skull base osteomyelitis. Conclusions: Otitis externa can be classified by seven degrees—1st degree: a normal canal but evidence of agitation; 2nd degree: wet debris and normal lumen but negative growth; 3rd degree: wet debris, negative growth with narrowed lumen; 4th degree: positive growth, normal lumen but minimal debris; 5th degree: positive growth, large amounts of debris; 6th degree: positive growth, debris and a narrowed lumen; 7th degree: complications.