Question 1

What is ICD-10 code B10.01?

Accepted Answer

B10.01 is the ICD-10-CM diagnosis code for human herpesvirus 6 encephalitis. An infection caused by human herpesvirus 6 that causes inflammation of the brain. B10.01 sits in the ICD-10-CM chapter for certain infectious and parasitic diseases (a00-b99), within the section covering other human herpesviruses (b10).

B10.01 has no mapping under the CMS-HCC V28 or V24 community payment models. B10.01 also appears in the HHS-HCC commercial risk model (HCC 003 (HHS-HCC 003 adult, RAF varies by metal level)), which is a commercial market model rather than a Medicare Advantage payment mapping. Do not assign V28 risk adjustment value from this page; verify the applicable model and payment year before using this code for risk adjustment.

Ensure documentation clearly states HHV-6 as the causative agent and confirms encephalitis diagnosis.

Question 2

Is B10.01 an HCC code?

Accepted Answer

B10.01 has no payable CMS-HCC V28 mapping in the final FY2026 CMS file.

Question 3

Is B10.01 billable?

Accepted Answer

Yes. B10.01 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. B10.01 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

Which HCC does B10.01 map to under V28?

Accepted Answer

B10.01 has no payable CMS-HCC V28 mapping in the final FY2026 CMS file.

Question 5

What RAF reference is published for B10.01?

Accepted Answer

B10.01 has no V28 reference coefficient because the final FY2026 source verifies no payable V28 mapping.

Question 6

What is the V28 vs V24 difference for B10.01?

Accepted Answer

B10.01 has verified no payable V28 mapping in the final FY2026 source. Select a historical effective period before making any V24 comparison.

Question 7

What documentation supports B10.01?

Accepted Answer

Ensure documentation clearly states HHV-6 as the causative agent and confirms encephalitis diagnosis This is a serious condition; verify appropriate severity documentation and any complications B10.01 is not a CMS-HCC V28 payment code in the verified current source, so MEAT is not the payment hook. Documentation still has to support the diagnosis if you report it.

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B10.01

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B10.01 ICD-10-CM Code: Human herpesvirus 6 encephalitis

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B10.01

Is B10.01 an HCC code?

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What This Code Means

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