M02.3 vs M45
M02.3 (Reiter's disease) compared with M45 (Ankylosing spondylitis), from the official CMS tabular data. Do not report these codes together: the official tabular list marks them Excludes1.
Can these codes be reported together?
No — do not report together. M45 carries an Excludes1 note covering M02.3: “arthropathy in Reiter's disease (M02.3-)”
Sole exception: when the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).
Side by side
| M02.3Reiter's disease | M45Ankylosing spondylitis | |
|---|---|---|
| Billing status | Non-billable header | Non-billable header |
| Classification | M00-M99 — Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) | M00-M99 — Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) |
| Definition | Reiter's disease is a non-billable ICD-10-CM category code (M02.3). | Ankylosing spondylitis is a non-billable ICD-10-CM category code (M45). |
| Includes | Reactive arthritis | Rheumatoid arthritis of spine |
| Code first | underlying disease, such as: congenital syphilis [Clutton's joints] (A50.5) | — |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources