Serious infections, left untreated, can also cause meningitis or mastoiditis, an infection of the mastoid bone in the skull, which requires surgery.

A story about Newman in the magazine Deaf Life said he was 5 when a chronic ear infection led to mastoiditis.

As mastoid complications may be mentioned: suppurative mastoiditis, leading to destruction of the bone, mastoid fistula, and sub-periosteal mastoid abscess.