Question 1

What is ICD-10 code D77?

Accepted Answer

D77 is the ICD-10-CM diagnosis code for other disorders of blood and blood-forming organs in diseases classified elsewhere. Blood and bone marrow disorders that occur as a complication of another disease classified elsewhere in the ICD-10 system. D77 sits in the ICD-10-CM chapter for diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (d50-d89), within the section covering other disorders of blood and blood-forming organs (d70-d77).

D77 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

This is a secondary code; the primary disease must be coded first.

Question 2

Is D77 an HCC code?

Accepted Answer

No. D77 is a billable ICD-10-CM code but does not map to any payment HCC category under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can still be reported on Medicare Advantage encounter data submissions, but it does not contribute to the beneficiary's Risk Adjustment Factor (RAF) score and therefore does not affect the risk-adjusted capitation payment to the plan. V28 reached 100% phase-in for payment year 2026.

Question 3

Is D77 billable?

Accepted Answer

Yes. D77 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. D77 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

Question 4

What is the V28 vs V24 difference for D77?

Accepted Answer

D77 does not map to a payment HCC under either the CMS-HCC V28 risk adjustment model or the older V24 model. V28 reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition. Because neither model rewards D77 with a risk adjustment factor, it contributes zero to a Medicare Advantage beneficiary's RAF score in either version. Coders should check whether provider documentation supports a more specific child code that does map to a payment HCC.

Question 5

What should coders know when reporting D77?

Accepted Answer

This is a secondary code; the primary disease must be coded first Review documentation carefully to identify the underlying condition causing the blood disorder

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D77

Is D77 an HCC code?

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D77 ICD-10-CM Code: Other disorders of blood and blood-forming organs in diseases classified elsewhere

HCC Buddy Code Card

D77

Is D77 an HCC code?

Get the V28 RAF + MEAT cheat sheet

What This Code Means

Coding Tips

Excludes 1, Do NOT code together

Code First

Code Hierarchy

Work D77 in HCC Buddy