Question 1

What is ICD-10 code N06.22?

Accepted Answer

N06.22 is the ICD-10-CM diagnosis code for secondary membranous nephropathy with isolated proteinuria. A kidney condition where protein leaks into the urine due to secondary damage to the kidney's filtering membranes, often caused by underlying diseases like lupus or infections. N06.22 sits in the ICD-10-CM chapter for diseases of the genitourinary system (n00-n99), within the section covering glomerular diseases (n00-n08).

N06.22 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 code requires documentation of the underlying cause of the secondary membranous nephropathy.

Question 2

Is N06.22 an HCC code?

Accepted Answer

No. N06.22 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 N06.22 billable?

Accepted Answer

Yes. N06.22 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. N06.22 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 N06.22?

Accepted Answer

N06.22 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 N06.22 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 N06.22?

Accepted Answer

This code requires documentation of the underlying cause of the secondary membranous nephropathy Verify that proteinuria is isolated (not accompanied by hematuria or other urinary findings)

N06.22

Is N06.22 an HCC code?

What This Code Means

Coding Tips

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Code Hierarchy

Open N06.22 in the Interactive Encoder