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A43

A43Nocardiosis

Non-billable headerICD-10-CM

A43 is a non-billable header ICD-10-CM code for nocardiosis. It cannot be billed on its own: choose one of the more specific child codes below.

Other codes that can never be billed with A43

These codes carry an Excludes1 note pointing at A43. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading A43 alone.

  • J17Pneumonia in diseases classified elsewhere

Risk adjustment

A43 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.

Code to one of these instead A43

4 child codes. Green means billable.

Questions about A43

Is A43 a billable ICD-10-CM code?
No. A43 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does A43 sit in the tabular list?
Certain infectious and parasitic diseases (A00-B99), in the block Other bacterial diseases (A30-A49).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.