ICD-10 Code M05.89 – Other rheumatoid arthritis with rheumatoid factor of multiple sites (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M05.89 – Other rheumatoid arthritis with rheumatoid factor of multiple sites
What it is
This code identifies rheumatoid arthritis with a positive rheumatoid factor when the record describes involvement of multiple joints but does not fit a more specific rheumatoid arthritis subtype. Use it for documented RA affecting several sites.
Clinical signs
Typical findings include symmetric inflammatory joint pain, swelling, stiffness, and reduced range of motion. Clinical features vary; refer to documentation for the specific joints involved and any confirmatory rheumatoid factor evidence.
When to use this code
Use M05.89 when the provider documents rheumatoid arthritis with rheumatoid factor and multiple joint sites, but no more specific M05 code applies. It is appropriate when the note supports seropositive RA and does not name a different coded subtype. Check documentation if the record only says “RA” or lists one joint.
Do not use for
Do not use this code for rheumatoid arthritis without rheumatoid factor, or when the chart identifies a more specific rheumatoid arthritis code. Also avoid it if the documentation does not clearly support multiple-site involvement.
Coding tip
Confirm both the rheumatoid factor status and the “multiple sites” wording before assigning M05.89.