ICD-10-CM 2027
ICD-10 code for Mediastinitis
From the official ICD-10-CM alphabetic index entry “Mediastinitis (acute) (chronic)”. Page updated September 29, 2026.
About coding Mediastinitis
The ICD-10-CM code for Mediastinitis is J98.51 (Mediastinitis). The official index lists 2 more specific codes, so check the documentation for details such as type, cause, site or severity before settling on J98.51.
Within J98.5 (diseases of mediastinum, not elsewhere classified), J98.51 is specifically for Mediastinitis. Related codes cover other diseases of mediastinum, not elsewhere classified (J98.59).
Code first: underlying condition, if applicable, such as postoperative mediastinitis (T81.-).
Use an additional code to identify: exposure to environmental tobacco smoke (Z77.22), exposure to tobacco smoke in the perinatal period (P96.81), history of tobacco dependence (Z87.891), occupational exposure to environmental tobacco smoke (Z57.31), tobacco dependence (F17.-) and 1 more.
More specific Mediastinitis codes (official index)
Common questions about Mediastinitis ICD-10 codes
What is the ICD-10 code for Mediastinitis?
- J98.51 — Mediastinitis. More specific codes apply when the documentation supports them: A52.73, A15.8.
What is the ICD-10 code for syphilitic mediastinitis?
- A52.73 — Symptomatic late syphilis of other respiratory organs.
What is the ICD-10 code for tuberculous mediastinitis?
- A15.8 — Other respiratory tuberculosis.
Is J98.51 billable?
- Yes. J98.51 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can J98.51 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict J98.51 as a principal diagnosis.
Is J98.51 a CC or MCC?
- J98.51 is an MCC (major complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.