Excludes1 pair
I01- vs I09-
I01 and I09 are not coded together. ICD-10-CM declares them mutually exclusive with an Excludes1 note — the two conditions are not expected to occur together, so exactly one of them is normally correct for a given encounter. The Official Guidelines carve out one exception: if the two conditions are clearly unrelated to each other, both may be reported.
The official note, declared on I01
chronic diseases of rheumatic origin (I05-I09) unless rheumatic fever is also present or there is evidence of reactivation or activity of the rheumatic process.
I01
Rheumatic fever with heart involvement
Not billable
- Chapter 9
- Diseases of the circulatory system
- Section
- I00-I02
Indexed under
- Fever › rheumatic › active with heart involvement
I09
Other rheumatic heart diseases
Not billable
- Chapter 9
- Diseases of the circulatory system
- Section
- I05-I09
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