Mastoiditis mimicry: retro-auricular cellulitis related to otitis externa.

Retro-auricular cellulitis associated with otitis externa is now the great mimicker of mastoiditis. It may be the most common cause of this specific cellulitis/auricular protrusion when it is associated with otitis externa. This column presents six cases of children who presented with peri-auricular redness, four of whom had protuberant ear and retro-auricular cellulitis.