Is D57.21 a billable ICD-10-CM code?

No. D57.21 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does D57.21 sit in the tabular list?

Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50-D89), in the block Hemolytic anemias (D55-D59).

What cannot be coded together with D57.21?

D57.21 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above D57.21 (D57) and apply to it just the same.

D57.21

D57.21 — Sickle-cell/Hb-C disease with crisis

Non-billable headerICD-10-CM

D57.21 is a non-billable header ICD-10-CM code for sickle-cell/hb-c disease with crisis. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes1 inherited from the categories above D57.21

These are not written on D57.21, but they bind it: a note on a category applies to every code beneath it. Billing D57.21 with anything listed here is a denial.

Written on D57 — Sickle-cell disorders

other hemoglobinopathies (D58.-)

Other codes that can never be billed with D57.21

These codes carry an Excludes1 note pointing at D57.21. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading D57.21 alone.

D56.8Other thalassemias

Risk adjustment

D57.21 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 history

D57.21 has not changed since FY2024 — no addition, revision or deletion across the three most recent ICD-10-CM releases.

Code to one of these instead D57.21

6 child codes. Green means billable.

Related codes at this level

Codes that share D57.2. If D57.21 is not quite right, the correct code is usually one of these.

D57.20Sickle-cell/Hb-C disease without crisis

Questions about D57.21

Is D57.21 a billable ICD-10-CM code?: No. D57.21 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does D57.21 sit in the tabular list?: Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D50-D89), in the block Hemolytic anemias (D55-D59).
What cannot be coded together with D57.21?: D57.21 carries Excludes1 notes, which means the conditions they list can never be coded together with it on the same encounter. Some are written on the categories above D57.21 (D57) and apply to it just the same.