Skip to content

N17.2 ICD-10-CM Code: Acute kidney failure with medullary necrosis

N17.2 is not a CMS-HCC payment code. MEAT criteria · RAF calculator · free HCC coding tools

ICD-10-CM Code View

HCC Buddy Code Card

Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

FY 2026 Apr update / Diseases of the genitourinary system (N00-N99) / Acute kidney failure and chronic kidney disease (N17-N19)

N17.2

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Acute kidney failure with medullary necrosis

A sudden loss of kidney function caused by tissue death in the inner part of the kidney (medulla). This is a serious condition that requires immediate medical attention.

Buddy the Bee presenting code insight

Buddy Insight

Acute kidney failure with medullary necrosis represents severe kidney injury with death of the inner kidney tissue, indicating critical illness with high morbidity and mortality.

CMS-HCC V28

N/A

Not mapped

CMS-HCC V24

HCC 135

RAF 0.435

ACA/HHS

N/A

Not mapped

ESRD/PACE

HCC 135

RAF 0.000

RXHCC

N/A

Not mapped

Code Book Path

Official
N17Acute kidney failure
N17.2Acute kidney failure with medullary necrosis

Inclusion Terms

Official
  • Medullary [papillary] necrosis NOS
  • Acute medullary [papillary] necrosis
  • Renal medullary [papillary] necrosis

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for N17.2 in this effective period.

Related Child Codes

Official
N17.0Acute kidney failure with tubular necrosis
N17.1Acute kidney failure with acute cortical necrosis
N17.8Other acute kidney failure
N17.9Acute kidney failure, unspecified

Includes

Official

ICD-10-CM does not list Includes notes for N17.2 in this effective period.

Excludes 1

Official
  • posttraumatic renal failure (T79.5)

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for N17.2 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for N17.2 in this effective period.

Code Also

Official
  • associated underlying condition

Buddy Documentation Tip

HCC Buddy guidance
Acute kidney failure with rapid onset clearly documented
Evidence of medullary necrosis through imaging or tissue studies
Laboratory findings demonstrating acute kidney function deterioration
Identification of underlying causes or precipitating factors

MEAT Support

HCC Buddy guidance
Acute kidney failure with rapid onset clearly documented
Evidence of medullary necrosis through imaging or tissue studies
Laboratory findings demonstrating acute kidney function deterioration
Identification of underlying causes or precipitating factors

Audit Caution

HCC Buddy guidance
Confusing medullary necrosis with cortical necrosis locations
Using unspecified acute kidney failure when necrosis type is documented
Not distinguishing acute failure with necrosis from chronic conditions
Failing to capture the severity and urgency indicated by medullary necrosis

Common Mistakes

HCC Buddy guidance
N17.1 — Acute kidney failure with acute cortical necrosis (different anatomical location)
N17.9 — Acute kidney failure, unspecified (lacks medullary necrosis specification)
N28.0 — Ischemia and infarction of kidney (vascular cause without acute failure)
N18.6 — End stage renal disease (chronic condition, not acute with necrosis)

Current with CMS: FY2026 ICD-10-CM Apr 1 update (effective Apr 1 – Sep 30, 2026) · CMS-HCC V28, 100% phased in for payment year 2026. FY2027 code set already staged for October 1, 2026. How HCC Buddy stays current →

Is N17.2 an HCC code?

Yes. N17.2 maps to Acute Renal Failure under the V24 model but is not retained in V28.

Code
N17.2
Description
Acute kidney failure with medullary necrosis
HCC (V28)
No CMS-HCC V28 mapping
RAF
Billable
Yes
Payment year
2026

HCC Category Mapping

V24HCC 135, Acute Renal Failure
0.435
ESRDHCC 135, Acute Renal Failure
0.000

Each model's RAF is its CMS base weight for that model's standard population, so weights are not directly comparable across models: CMS-HCC V28 and V24 use Community, Non-Dual, Aged; ESRD uses the dialysis continuing-enrollee model; RxHCC is the Part D continuing-enrollee, non-low-income, aged weight (a larger scale than CMS-HCC). ACA/HHS has no single weight — it varies by metal level. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.

Work N17.2 in the Code Book — tabular path, V28 RAF, and MEAT checklist →

MEAT Criteria for N17.2

For N17.2 to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.

  • MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
  • EEvaluate: test results, medication response, or physical findings reviewed by the provider
  • AAssess: explicit mention in the assessment or plan with acknowledgment of status
  • TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis

Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed N17.2 during that encounter, not just copy-forwarded from a problem list.

Coder workflow notes

Get the V28 RAF + MEAT cheat sheet

One printable page: confirm a code's V28 HCC status, its RAF weight, and the MEAT your note needs to make it stick. Free, no card.

Free PDF. No card. Unsubscribe anytime.

What This Code Means

N17.2 is the ICD-10-CM diagnosis code for acute kidney failure with medullary necrosis. A sudden loss of kidney function caused by tissue death in the inner part of the kidney (medulla). This is a serious condition that requires immediate medical attention. N17.2 sits in the ICD-10-CM chapter for diseases of the genitourinary system (n00-n99), within the section covering acute kidney failure and chronic kidney disease (n17-n19).

Under the older CMS-HCC V24 model, N17.2 maps to Acute Renal Failure (HCC 135) with a community, non-dual, aged base RAF weight of 0.435. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.

This code indicates a specific type of acute kidney injury with medullary necrosis; ensure clinical documentation supports this specific finding rather than using the unspecified code N17.9. Because N17.2 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for N17.2 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

  • This code indicates a specific type of acute kidney injury with medullary necrosis; ensure clinical documentation supports this specific finding rather than using the unspecified code N17.9
  • Look for associated conditions like sepsis, severe dehydration, or nephrotoxic drug exposure that may have triggered the medullary necrosis

Clinical Significance

Acute kidney failure with medullary necrosis represents severe kidney injury with death of the inner kidney tissue, indicating critical illness with high morbidity and mortality. This condition requires immediate aggressive treatment and has significant impact on healthcare resource utilization.

Documentation Requirements

  • Acute kidney failure with rapid onset clearly documented
  • Evidence of medullary necrosis through imaging or tissue studies
  • Laboratory findings demonstrating acute kidney function deterioration
  • Identification of underlying causes or precipitating factors
  • Treatment plan including dialysis considerations
  • Monitoring protocols for kidney function and complications
  • Assessment of prognosis and potential for recovery

Commonly Confused Codes

  • N17.1: Acute kidney failure with acute cortical necrosis (different anatomical location)
  • N17.9: Acute kidney failure, unspecified (lacks medullary necrosis specification)
  • N28.0: Ischemia and infarction of kidney (vascular cause without acute failure)
  • N18.6: End stage renal disease (chronic condition, not acute with necrosis)

Child Codes

Code Hierarchy

N17Acute kidney failureN17.2Acute kidney failure with medullary necrosis
N17.2Acute kidney failure with medullary necrosis

Because N17.2 maps to a payment HCC, the documentation must also satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's risk adjustment score.

Work N17.2 in HCC Buddy

Open N17.2 in the Code Book for the full Index-to-Tabular path, MEAT checklist, and V28 HCC mapping, or in the Encoder to code from a keyword search. Pro includes 7 days to try everything, no card required.