ICD-10 Code H75.02 – Mastoiditis in infectious and parasitic diseases classified elsewhere, left ear (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code H75.02 – Mastoiditis in infectious and parasitic diseases classified elsewhere, left ear
What it is
H75.02 identifies mastoiditis of the left ear that is coded to an underlying infectious or parasitic disease elsewhere in the classification. Use it when the mastoid inflammation is linked to another documented infection.
Clinical signs
Findings may include ear pain, tenderness behind the ear, swelling, and mastoid inflammation on exam or imaging. Clinical features vary; refer to documentation.
When to use this code
Use this code when the record states left-sided mastoiditis and the provider documents an infectious or parasitic condition causing it. The underlying disease should also be coded when documented. Check documentation if laterality or the causal infection is unclear.
Do not use for
Do not use it for unspecified mastoiditis, right ear disease, or mastoiditis without an identified infectious or parasitic cause. Do not use it when the chart does not support the left-ear site.
Coding tip
Confirm both laterality and the underlying infection before assigning H75.02.