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You are seeing a 3 year old child with acute onset draining right ear. The child has no fever and no history of recent swimming or other risk factors for otitis externa. The child has a PMH of frequent otitis media, and pressure equalization (tympanostomy) tubes were placed at age 1 year. There have been no episodes of otitis media since then. As far as the parents know, the tubes are still in place, but they have not had any follow-up with an ENT. On exam, the left ear canal has a PE tube laying in the canal, which you remove; the tympanic membrane is translucent and mobile. The right canal is full of seropurulent drainage. You cannot see the tympanic membrane nor any PE tube. The canal itself is not swollen or red.