ICD-10 Code J84.11 – Idiopathic Interstitial Pneumonia (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code J84.11 – Idiopathic interstitial pneumonia
What it is
J84.11 identifies idiopathic interstitial pneumonia, a lung disorder in which the interstitial tissue becomes inflamed or scarred without a known cause. Use it when the record specifically documents this diagnosis.
Clinical signs
Clinical features vary; refer to documentation. Commonly reported findings include progressive shortness of breath, dry cough, and interstitial changes on imaging or other pulmonary evaluation.
When to use this code
Use J84.11 when the provider documents idiopathic interstitial pneumonia, including idiopathic interstitial lung disease described with this exact diagnosis. It is appropriate for confirmed cases in outpatient, inpatient, or consult notes when the condition is the reason for care or a relevant comorbidity. Check documentation if the note names a more specific interstitial pneumonia subtype.
Do not use for
Do not use this code for interstitial lung disease with an identified cause, such as exposure-related or autoimmune disease-related fibrosis. Do not assign it when the chart only says “interstitial changes” without a documented idiopathic interstitial pneumonia diagnosis.
Coding tip
Code the documented diagnosis as written and verify whether a more specific interstitial lung disease code applies before defaulting to J84.11.