Is D84.81 a billable ICD-10-CM code?

Yes. D84.81 is a billable, specific ICD-10-CM code and is valid for submission on a claim.

Where does D84.81 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 Certain disorders involving the immune mechanism (D80-D89).

What cannot be coded together with D84.81?

D84.81 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

D84.81

D84.81 — Immunodeficiency due to conditions classified elsewhere

Billable / specific codeICD-10-CM

D84.81 is a billable, specific ICD-10-CM code for immunodeficiency due to conditions classified elsewhere. 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.

certain disorders involving the immune mechanism (D80-D83, D84.0, D84.1, D84.9)
human immunodeficiency virus [HIV] disease (B20)

Code first

The underlying condition must be sequenced before this code.

underlying condition, such as:
chromosomal abnormalities (Q90-Q99)
diabetes mellitus (E08-E13)
malignant neoplasms (C00-C96)

Risk adjustment

D84.81 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

D84.81 is named in 5 Medicare coverage policies — 5 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

A56464Billing and Coding: Flow Cytometry
A56638Billing and Coding: Gastrointestinal Pathogen (GIP) Panels Utilizing Multiplex Nucleic Acid Amplification Techniques (NAATs)
A56642Billing and Coding: Gastrointestinal Pathogen (GIP) Panels Utilizing Multiplex Nucleic Acid Amplification Techniques (NAATs)
A57044Billing and Coding: Removal of Benign Skin Lesions

How D84.81 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 D84.81.

Immunodeficiency›due to›conditions classified elsewhere

Related codes at this level

Codes that share D84.8. If D84.81 is not quite right, the correct code is usually one of these.

Questions about D84.81

Is D84.81 a billable ICD-10-CM code?: Yes. D84.81 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does D84.81 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 Certain disorders involving the immune mechanism (D80-D89).
What cannot be coded together with D84.81?: D84.81 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.