ICD-10 Code H70.93 – Unspecified Mastoiditis, Bilateral (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H70.93 – Unspecified mastoiditis, bilateral
What it is
H70.93 identifies mastoid inflammation affecting both mastoid processes, with the specific cause or type not documented. Use it when the record confirms bilateral mastoiditis but does not specify acute, chronic, or another form.
Clinical signs
Clinical features vary; refer to documentation. Typical findings may include ear pain, mastoid tenderness, swelling behind the ear, or signs of ear infection, but the chart must support bilateral mastoid involvement.
When to use this code
Use this code when the clinician documents unspecified mastoiditis on both sides and no more specific mastoiditis code is available. It may apply when imaging, exam, or operative notes confirm bilateral disease, but the record does not define the type. Check documentation if laterality or acuity is unclear.
Do not use for
Do not use H70.93 if the record identifies acute, chronic, or other specified mastoiditis. Do not assign it for unilateral disease or for nonspecific ear infection without documented mastoid involvement.
Coding tip
Verify both laterality and specificity in the note before selecting H70.93.