J16 vs J18.9
J16 and J18.9 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.
The official note, declared on J16
pneumonia NOS (J18.9)
J16
Pneumonia due to other infectious organisms, not elsewhere classified
Not billable
- Chapter 10
- Diseases of the respiratory system
- Section
- J09-J18
J18.9
Pneumonia, unspecified organism
BillableUnspecified
- Chapter 10
- Diseases of the respiratory system
- Section
- J09-J18
Indexed under
- Pneumonia (acute) (double) (migratory) (purulent) (septic) (unresolved)
- Infection, infected, infective › lung (opportunistic)
- Pneumonia › atypical NEC (acute) (double) (migratory) (purulent) (septic) (unresolved)
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