ICD-10 Code I79.1 – Aortitis in diseases classified elsewhere (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I79.1 – Aortitis in diseases classified elsewhere
What it is
I79.1 identifies inflammation of the aorta that is caused by another underlying disease. Use it when the aortitis is documented as secondary, not as a primary aortic disorder.
Clinical signs
Clinical features vary; refer to documentation. Common references describe chest or back pain, constitutional symptoms, and imaging or pathology evidence of aortic inflammation linked to another condition.
When to use this code
Use this code when the provider states aortitis is due to a disease classified elsewhere, such as an autoimmune or infectious process. Code the underlying condition first when instructed by the record and guidelines. Confirm that the documentation clearly links the aortic inflammation to that cause.
Do not use for
Do not use I79.1 for primary aortitis or for nonspecific aortic disease without a documented secondary cause. Check documentation if the note does not clearly connect the aortitis to another disease.
Coding tip
Always look for the underlying disease and sequence it appropriately before assigning I79.1.