N49.3
BillableFournier gangrene
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is N49.3 an HCC code?
Yes. N49.3 maps to Bone/Joint/Muscle Infections/Necrosis under the CMS-HCC V28 risk adjustment model.
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. 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.
MEAT Criteria for N49.3
For N49.3 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 N49.3 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
N49.3 is the ICD-10-CM diagnosis code for fournier gangrene. A rapidly spreading, life-threatening bacterial infection of the genital area and surrounding tissues that causes tissue death. N49.3 sits in the ICD-10-CM chapter for diseases of the genitourinary system (n00-n99), within the section covering diseases of male genital organs (n40-n53).
Under the CMS-HCC V28 risk adjustment model, N49.3 maps to Bone/Joint/Muscle Infections/Necrosis (HCC 92) with a community, non-dual, aged base RAF weight of 0.209. N49.3 was not retained as a payment HCC under the older V24 model, so V28 introduced or recategorized it during the 2024–2026 phase-in. 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 is a medical emergency; ensure documentation reflects the severity and urgency of treatment. Because N49.3 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 N49.3 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •This is a medical emergency; ensure documentation reflects the severity and urgency of treatment
- •Code the causative organism separately if identified (typically polymicrobial); this condition often requires sepsis coding as well
Clinical Significance
Fournier gangrene is a urological emergency with high mortality risk, requiring immediate surgical debridement and aggressive antibiotic therapy. This necrotizing fasciitis of the genitalia and perineum represents one of the most severe soft tissue infections, making accurate coding essential for risk adjustment.
Documentation Requirements
- ✓Clinical diagnosis of necrotizing fasciitis of male genitalia
- ✓Documentation of tissue necrosis and gangrene
- ✓Evidence of systemic toxicity or sepsis
- ✓Surgical debridement or intervention records
- ✓Microbiological culture results when available
- ✓Assessment of extent of tissue involvement
- ✓Treatment with broad-spectrum antibiotics
- ✓Monitoring for complications and organ dysfunction