ICD-10 Code H70.893 – Other mastoiditis and related conditions, bilateral (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H70.893 – Other mastoiditis and related conditions, bilateral
What it is
This code identifies bilateral mastoid inflammation or related mastoid conditions that do not fit a more specific ICD-10 category. It tells you the condition involves both mastoid processes.
Clinical signs
Clinical features vary; refer to documentation. Commonly documented findings may include mastoid tenderness, swelling, redness, ear pain, or ear drainage, with involvement on both sides.
When to use this code
Use this code when the provider documents other mastoiditis or a related mastoid condition affecting both ears and no more specific code applies. It is appropriate when laterality is clearly documented as bilateral. If the note only says mastoiditis without further detail, check documentation before coding.
Do not use for
Do not use this code for unilateral mastoiditis or for a more specific mastoid diagnosis that is documented elsewhere. If the record does not support bilateral involvement, check documentation.
Coding tip
Always verify bilateral laterality in the provider note before assigning H70.893.