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D72.821

D72.821Monocytosis (symptomatic)

Billable / specific codeICD-10-CM

D72.821 is a billable, specific ICD-10-CM code for monocytosis (symptomatic). It is valid for submission on a claim.

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

  • infectious mononucleosis (B27.-)

Risk adjustment

D72.821 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

D72.821 is named in 17 Medicare coverage policies 17 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A55717Billing and Coding: Lab: Flow Cytometry
  • A56199Billing and Coding: Molecular Pathology Procedures
  • A56199Billing and Coding: Molecular Pathology Procedures
  • A56199Billing and Coding: Molecular Pathology Procedures

How D72.821 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 D72.821.

  • Monocytosis(symptomatic)

Related codes at this level

Codes that share D72.82. If D72.821 is not quite right, the correct code is usually one of these.

Questions about D72.821

Is D72.821 a billable ICD-10-CM code?
Yes. D72.821 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does D72.821 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 Other disorders of blood and blood-forming organs (D70-D77).
What cannot be coded together with D72.821?
D72.821 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.
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.