M05.80 is the authoritative medical code for Other rheumatoid arthritis with rheumatoid factor of unspecified site. This classification is used in medical billing and clinical recording to specify the clinical criteria for other rheumatoid arthritis with rheumatoid factor of unspecified site (ICD-10-CM M05.80), ensuring healthcare documentation aligns with 2026 federal coding standards.
Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.
Official Registry Overview & Definition
Other rheumatoid arthritis with rheumatoid factor of unspecified site is a billable ICD-10-CM diagnosis code M05.80. Excludes1 (not coded here): rheumatic fever I00; juvenile rheumatoid arthritis M08.-; rheumatoid arthritis of spine M45.-.
Official Tabular Instructional Notes
Sequencing, inclusion, and exclusion notes published for M05.80 in the official ICD-10-CM tabular list.
Excludes1 — Not Coded Here
Conditions that can never be reported with this code; the two are mutually exclusive.
- rheumatic fever I00
- juvenile rheumatoid arthritis M08.-
- rheumatoid arthritis of spine M45.-
Frequently Asked Questions (FAQ) & Clinical Guidance
What can't be coded together with M05.80?
Per official ICD-10-CM Excludes1 instructions, M05.80 must not be reported together with: rheumatic fever (I00); juvenile rheumatoid arthritis (M08.-); rheumatoid arthritis of spine (M45.-).
Nearest Codes in This Family
Official ICD-10-CM classifications closest to M05.80 in its code family, with their registry titles.
- M05 — Rheumatoid arthritis with rheumatoid factor
- M05-M14 — Inflammatory polyarthropathies (M05-M14)
- M05.0 — Felty's syndrome
- M05.00 — Felty's syndrome, unspecified site
- M05.01 — Felty's syndrome, shoulder
- M05.011 — Felty's syndrome, right shoulder
- M05.012 — Felty's syndrome, left shoulder
- M05.019 — Felty's syndrome, unspecified shoulder
- M05.02 — Felty's syndrome, elbow
- M05.021 — Felty's syndrome, right elbow
View all 40 codes in the M05 family
Indexed Clinical Terms (1)
Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code.
- Arthritis, arthritic (acute) (chronic) (nonpyogenic) (subacute), rheumatoid, seropositive, specified NEC