Question 1

What is ICD-10 code A18.6?

Accepted Answer

A18.6 is the ICD-10-CM diagnosis code for tuberculosis of (inner) (middle) ear. This is a tuberculosis infection that affects the ear, specifically the inner or middle ear structures. It's a serious infection caused by the tuberculosis bacterium spreading to the ear. A18.6 sits in the ICD-10-CM chapter for certain infectious and parasitic diseases (a00-b99), within the section covering tuberculosis (a15-a19).

A18.6 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.

Verify documentation specifies tuberculosis of the ear and confirm whether it involves the inner ear, middle ear, or both before coding.

Question 2

Is A18.6 an HCC code?

Accepted Answer

No. A18.6 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 A18.6 billable?

Accepted Answer

Yes. A18.6 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. A18.6 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 A18.6?

Accepted Answer

A18.6 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 A18.6 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 A18.6?

Accepted Answer

Verify documentation specifies tuberculosis of the ear and confirm whether it involves the inner ear, middle ear, or both before coding This code should be used in conjunction with the primary tuberculosis code (typically from A15-A19 range) to fully capture the patient's TB diagnosis and its site of infection

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A18.6

Is A18.6 an HCC code?

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A18.6 ICD-10-CM Code: Tuberculosis of (inner) (middle) ear

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A18.6

Is A18.6 an HCC code?

Get the V28 RAF + MEAT cheat sheet

What This Code Means

Coding Tips

Excludes 2, Not included here, may code separately

Child Codes

Code Hierarchy

Work A18.6 in HCC Buddy