Subperiosteal abscess of mastoid, unspecified ear

This code signifies an infection forming a collection of pus beneath the periosteum of the mastoid bone, where the specific ear affected is not documented. This condition is typically a complication of acute otitis media or mastoiditis, indicating a more severe progression of the infection. It can lead to significant pain, swelling behind the ear, and potential intracranial complications if left untreated.

Use this code when the medical record clearly documents a subperiosteal abscess of the mastoid, but the laterality (left, right, or bilateral) is not specified. This diagnosis is often made based on clinical examination findings, imaging studies such as CT scans, and sometimes surgical exploration. Documentation should explicitly state "subperiosteal mastoid abscess" without specifying the ear.

• Avoid using this code if the medical record specifies the affected ear; instead, use H70.011 (right ear) or H70.012 (left ear).
• Always query the provider for laterality if it's not documented to ensure the most specific code is assigned.
• Consider sequencing this code after a code for the underlying condition, such as acute mastoiditis (H70.00- series), if applicable and documented.