ICD-10-CM 2027
ICD-10 code for inflammatory polyarthritis
From the official ICD-10-CM alphabetic index entry “Polyarthritis, polyarthropathy › inflammatory”. Page updated September 29, 2026.
About coding inflammatory polyarthritis
The ICD-10-CM code for inflammatory polyarthritis is M06.4 (Inflammatory polyarthropathy).
Within M06 (other rheumatoid arthritis), M06.4 is specifically for inflammatory polyarthropathy. Related codes cover rheumatoid arthritis without rheumatoid factor (M06.0), Adult-onset Still's disease (M06.1), rheumatoid bursitis (M06.2), rheumatoid nodule (M06.3), other specified rheumatoid arthritis (M06.8) and rheumatoid arthritis, unspecified (M06.9).
Don't report M06.4 together with the conditions in its Excludes1 note: polyarthritis NOS (M13.0).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
Don't confuse with (Excludes1 for M06.4)
- polyarthritis NOS (M13.0)
Common questions about inflammatory polyarthritis ICD-10 codes
What is the ICD-10 code for inflammatory polyarthritis?
- M06.4 — Inflammatory polyarthropathy.
Is M06.4 billable?
- Yes. M06.4 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can M06.4 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict M06.4 as a principal diagnosis.
Is M06.4 a CC or MCC?
- No. M06.4 is neither a CC nor an MCC under MS-DRG v44.0.