Alphabetic Index FY2027

M31

Other necrotizing vasculopathies

FY2027Chapter 13: Diseases of the musculoskeletal system and connective tissue/M30–M36 Systemic connective tissue disorders

Non-billable headerNot valid on its own. Use one of the more specific codes under it.

M31 is a non-billable ICD-10-CM code category for other necrotizing vasculopathies. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are M31.0 Hypersensitivity angiitis, M31.1 Thrombotic microangiopathy, M31.2 Lethal midline granuloma, M31.3 Wegener's granulomatosis and 6 more. Its coding notes include 1 Excludes1 entry and 10 Excludes2 entries.

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Also from chapter/block level (1 note)
Inherited from M30–M36 Systemic connective tissue disorders
  • autoimmune disease, single organ or single cell-type -code to relevant condition category

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Also from chapter/block level (10 notes)
Inherited from Chapter 13 Diseases of the musculoskeletal system and connective tissue
  • arthropathic psoriasis (L40.5-)
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • compartment syndrome (traumatic) (T79.A-)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Includes

Further defines or gives examples of the content of the category.

Also from chapter/block level (4 notes)
Inherited from M30–M36 Systemic connective tissue disorders
  • autoimmune disease NOS
  • collagen (vascular) disease NOS
  • systemic autoimmune disease
  • systemic collagen (vascular) disease

Notes

Also from chapter/block level (1 note)
Inherited from Chapter 13 Diseases of the musculoskeletal system and connective tissue
  • Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition

More specific codes under M31 10