ICD-10 Code H70.92 – Unspecified mastoiditis, left ear (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H70.92 – Unspecified mastoiditis, left ear
What it is
H70.92 identifies mastoiditis affecting the left ear when the record does not specify the type. Use it for inflammation or infection of the mastoid region behind the left ear without further detail.
Clinical signs
Typical findings may include ear pain, tenderness over the mastoid, swelling, and redness behind the ear. Clinical features vary; refer to documentation.
When to use this code
Use H70.92 when the provider documents mastoiditis of the left ear but does not name an acute, chronic, or other specific form. It also fits when the chart confirms mastoid involvement on the left and no more precise diagnosis is available.
Do not use for
Do not use this code if the record identifies a different mastoiditis type or a right-sided or bilateral condition. Check documentation when the diagnosis is only suspected or not clearly confirmed.
Coding tip
Always verify laterality and specificity in the note before assigning H70.92.