ICD-10 Code J84.111 – Idiopathic Interstitial Pneumonia, Not Otherwise Specified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code J84.111 – Idiopathic interstitial pneumonia, not otherwise specified
What it is
Use this code for an idiopathic interstitial pneumonia when the record does not identify a more specific subtype. It refers to diffuse lung disease with interstitial inflammation or fibrosis and no known cause.
Clinical signs
Patients commonly have progressive shortness of breath, dry cough, and abnormal chest imaging consistent with interstitial lung disease. Clinical features vary; refer to documentation.
When to use this code
Use J84.111 when the provider documents idiopathic interstitial pneumonia and does not specify a named form such as usual interstitial pneumonia or nonspecific interstitial pneumonia. It may also apply when the note explicitly states “not otherwise specified.” Check documentation if another interstitial lung disease is named.
Do not use for
Do not use this code for interstitial lung disease with a known cause, such as exposure-related, autoimmune, or drug-induced disease. Do not use it when a more specific idiopathic interstitial pneumonia subtype is documented.
Coding tip
Code the most specific interstitial pneumonia documented; if the subtype is unclear, query the provider before assigning J84.111.