M04.9
Autoinflammatory syndrome, unspecified
BillableComplete code, valid to report
M04.9 (also written M049) is a billable ICD-10-CM diagnosis code for autoinflammatory syndrome, unspecified. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 5 codes in category M04 (Autoinflammatory syndromes). The Alphabetic Index lists it under 2 entries. Its coding notes include 11 Excludes2 entries.
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)
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
Alphabetic Index terms
Terms the official Alphabetic Index lists for this code. 2 entries