B97.4 vs J21.0
B97.4 and J21.0 can never be reported together. ICD-10-CM declares them mutually exclusive with an Excludes1 note, meaning the two conditions cannot occur in the same patient — so exactly one of them is correct for any given encounter.
Respiratory syncytial virus as the cause of diseases classified elsewhere
- Chapter 1
- Certain infectious and parasitic diseases
- Section
- B95-B97
- RSV as the cause of diseases classified elsewhere
- Respiratory › syncytial virus, as cause of disease classified elsewhere
- Virus, viral › respiratory syncytial › as cause of disease classified elsewhere
- Virus, viral › respiratory syncytial › otitis media
- Virus, viral › respiratory syncytial › upper respiratory infection
- Infection, infected, infective › virus, viral NOS › respiratory syncytial › as cause of disease classified elsewhere (opportunistic)
Acute bronchiolitis due to respiratory syncytial virus
- Chapter 10
- Diseases of the respiratory system
- Section
- J20-J22
- Acute bronchiolitis due to RSV
- Bronchiolitis › due to › respiratory syncytial virus (acute) (infective) (subacute)
- Virus, viral › respiratory syncytial › bronchiolitis
- Infection, infected, infective › virus, viral NOS › respiratory syncytial › bronchiolitis (opportunistic)
These two codes sit in different chapters of the Tabular List, which is usually the clearest signal that they describe different underlying processes rather than different degrees of the same one.
Excludes1 is not always absolute: where two conditions covered by the note are genuinely unrelated, CMS guidance permits reporting both. Document the reasoning rather than assuming it. More on Excludes1 vs Excludes2 · FY2027