D66 — Hereditary factor VIII deficiency
D66 is a billable, specific ICD-10-CM code for hereditary factor viii deficiency. 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.
- factor VIII deficiency with vascular defect (D68.0-)
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Classical hemophilia
- Deficiency factor VIII (with functional defect)
- Hemophilia NOS
- Hemophilia A
Other codes that can never be billed with D66
These codes carry an Excludes1 note pointing at D66. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading D66 alone.
- D68.0Von Willebrand disease
Risk adjustment
D66 risk-adjusts. Under the CMS-HCC V28 model it maps to these categories:
- HCC 111 Hemophilia, Male4.639 RAF
- HCC 111 Hemophilia, Male4.639 RAF
- HCC 112 Immune Thrombocytopenia and Specified Coagulation Defects and Hemorrhagic Conditions0.450 RAF
Coefficient shown for the Community Non-dual Aged segment. A higher HCC in the same hierarchy will suppress this one, so capturing it does not always add score.
Medicare coverage
D66 is named in 4 Medicare coverage policies — 4 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A56065Billing and Coding: Guidance for Anti-Inhibitor Coagulant Complex (AICC) National Coverage Determination (NCD) 110.3
- A56065Billing and Coding: Guidance for Anti-Inhibitor Coagulant Complex (AICC) National Coverage Determination (NCD) 110.3
- A56065Billing and Coding: Guidance for Anti-Inhibitor Coagulant Complex (AICC) National Coverage Determination (NCD) 110.3
- A56065Billing and Coding: Guidance for Anti-Inhibitor Coagulant Complex (AICC) National Coverage Determination (NCD) 110.3
How D66 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 D66.
- Hemophilia(classical) (familial) (hereditary)
- Subhemophilia
- Arthropathy›hemophilic NEC
- Disease, diseased›bleeder's
- Hemophilia›A
- Arthritis, arthritic›due to or associated with›hemophilia
- Arthritis, arthritic›in›hemophilia NEC
- Arthropathy›in›hemophilia NEC
- Deficiency, deficient›anti-hemophilic›factor(A)
- Deficiency, deficient›anti-hemophilic›globulin NEC(AHG)
- Deficiency, deficient›factor›VIII(congenital) (functional) (hereditary) (with functional defect)
Questions about D66
- Is D66 a billable ICD-10-CM code?
- Yes. D66 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does D66 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 Coagulation defects, purpura and other hemorrhagic conditions (D65-D69).
- What cannot be coded together with D66?
- D66 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.