Question 1

What is ICD-10 code N06.20?

Accepted Answer

N06.20 is the ICD-10-CM diagnosis code for isolated proteinuria with diffuse membranous glomerulonephritis, unspecified. A condition where protein is found in the urine caused by membranous glomerulonephritis, a disease affecting the membrane that filters waste in the kidneys, with the specific type not further specified. N06.20 sits in the ICD-10-CM chapter for diseases of the genitourinary system (n00-n99), within the section covering glomerular diseases (n00-n08).

N06.20 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.

N06.20 is used when membranous nephropathy is present but it's unclear whether it's primary or secondary.

Question 2

Is N06.20 an HCC code?

Accepted Answer

No. N06.20 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 N06.20 billable?

Accepted Answer

Yes. N06.20 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. N06.20 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 N06.20?

Accepted Answer

N06.20 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 N06.20 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 N06.20?

Accepted Answer

N06.20 is used when membranous nephropathy is present but it's unclear whether it's primary or secondary If primary membranous nephropathy is confirmed, use N06.21 instead; if secondary, specify the underlying cause

N06.20

Is N06.20 an HCC code?

What This Code Means

Coding Tips

Excludes 1 — Do NOT code together

Code Hierarchy

Open N06.20 in the Interactive Encoder