I00 — Rheumatic fever without heart involvement
I00 is a billable, specific ICD-10-CM code for rheumatic fever without heart involvement. It is valid for submission on a claim.
Other codes that can never be billed with I00
These codes carry an Excludes1 note pointing at I00. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading I00 alone.
Risk adjustment
I00 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
I00 is named in 1 Medicare coverage policy — 1 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A57326Billing and Coding: Electrocardiograms
How I00 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to I00.
- Fever›rheumatic(active) (acute) (chronic) (subacute)
- Pneumonia›rheumatic
- Rheumatic›pneumonia
- Erythema, erythematous›marginatum›in acute rheumatic fever(due to)
- Pneumonia›in›rheumatic fever
Questions about I00
- Is I00 a billable ICD-10-CM code?
- Yes. I00 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does I00 sit in the tabular list?
- Diseases of the circulatory system (I00-I99), in the block Acute rheumatic fever (I00-I02).
- What cannot be coded together with I00?
- I00 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.