ICD-10 · PDGM grouping
M31 Other necrotizing vasculopathies
All 13 codes in the M31 family, with the PDGM clinical group, comorbidity subgroup and primary-position rule CMS assigns, read from the CMS grouper crosswalk v07.2.26 and the CDC FY2027 code file.
Codes in family
13
Can lead a claim
12
Cannot lead a claim
1
What CMS assigns to M31
12 of the 13 codes group to MMTA - Other; 1 is assigned no clinical group. None of the 13 is assigned a comorbidity subgroup. 12 of the 13 can lead a claim. CMS attaches a code-first note to 1 of the 13.
Code first
CMS grouper convention 117, on M31.11. Code first:
- complications of bone marrow transplant (T86.0-)
- complications of stem cell transplant (T86.5)
- if applicable:
Every code in M31
Descriptions are CDC’s FY2027 wording; where CMS’s grouper abbreviates one, its form is shown beneath.
| Code | Description | Primary position | Clinical group | Comorbidity subgroup |
|---|---|---|---|---|
| M31.0 | Hypersensitivity angiitis | Can lead a claim | A | None |
| M31.1 Thrombotic microangiopathy | ||||
| M31.10 | Thrombotic microangiopathy, unspecified | Can lead a claim | A | None |
| M31.11 | Hematopoietic stem cell transplantation-associated thrombotic microangiopathy [HSCT-TMA]CMS: Hematpoetc stem cell txpltation-assoc throm microangiopathy | Cannot lead a claimPrincipal diagnosis not assigned to a clinical group | None | None |
| M31.19 | Other thrombotic microangiopathy | Can lead a claim | A | None |
| M31.2 | Lethal midline granuloma | Can lead a claim | A | None |
| M31.3 Wegener's granulomatosis | ||||
| M31.30 | Wegener's granulomatosis without renal involvement | Can lead a claim | A | None |
| M31.31 | Wegener's granulomatosis with renal involvement | Can lead a claim | A | None |
| M31.4 | Aortic arch syndrome [Takayasu] | Can lead a claim | A | None |
| M31.5 | Giant cell arteritis with polymyalgia rheumatica | Can lead a claim | A | None |
| M31.6 | Other giant cell arteritis | Can lead a claim | A | None |
| M31.7 | Microscopic polyangiitis | Can lead a claim | A | None |
| M31.8 | Other specified necrotizing vasculopathies | Can lead a claim | A | None |
| M31.9 | Necrotizing vasculopathy, unspecified | Can lead a claim | A | None |
Sources: CMS HH PPS Grouper Software v07.2.26, effective 2026-10-01, for the clinical group, comorbidity subgroup, code-first conventions and primary-position flags; CDC NCHS ICD-10-CM FY2027 code descriptions for the family title and code wording. This is the crosswalk Medicare runs a claim through. Grouping also depends on admission source, timing, the OASIS functional items and the rest of the diagnosis list.
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