ICD-10 Code J85 – Abscess of lung and mediastinum (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code J85 – Abscess of lung and mediastinum
What it is
J85 identifies a localized collection of pus in the lung or mediastinum. Use it when documentation states a lung abscess, mediastinal abscess, or both.
Clinical signs
Clinical features vary; refer to documentation. Commonly, records describe cough, fever, chest pain, or imaging findings consistent with a cavitary or localized infectious process.
When to use this code
Use J85 when the provider documents an abscess involving the lung or mediastinum and no more specific code is available. It may also fit cases described as a pulmonary abscess or mediastinal abscess in the assessment.
If the note identifies a different infectious site or a postoperative collection without an abscess diagnosis, check documentation before coding J85. Confirm that the record supports an abscess rather than another pulmonary or mediastinal condition.
Do not use for
Do not use this code for pneumonia, empyema, or nonspecific chest infection unless an abscess is documented. Do not assign it for postoperative fluid collections without confirmation of abscess.
Coding tip
Code J85 only when the provider clearly names the abscess site; if the location is unclear, check documentation.