2026 ICD-10-CM Diagnosis Code M06.4Inflammatory polyarthropathy
ICD-10-CM Codes›M00–M99›M05-M14›M06
- Billable — Valid for Submission
- Chronic Condition
M06.4 is a billable ICD-10-CM diagnosis code for inflammatory polyarthropathy. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 553 through 554. Coders also document this condition as autoimmune leukopenia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Rheumatoid arthritis and related disease.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Autoimmune leukopenia
- Idiopathic polyarthritis
- Immune dysregulation, inflammatory bowel disease, arthritis, recurrent infection, lymphopenia syndrome
- Inflammatory polyarthropathy
- Lymphocyte count below reference range
- Lymphocytopenia
- Pyoderma gangrenosum due to inflammatory polyarthropathy
- Undifferentiated inflammatory arthritis
- Undifferentiated inflammatory polyarthritis
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Type 1 Excludes
- polyarthritis NOS M13.0
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
- Polyarthritis, polyarthropathy - See Also: Arthritis; - M13.0
- inflammatory - M06.4
External Cause of Injuries IndexGuidance
References for this code in the External Cause of Injuries Index.
- Polyarthritis, polyarthropathy
- inflammatory
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Arthritis
If you feel pain and stiffness in your body or have trouble moving around, you might have arthritis. Any disorder that affects the joints is often called arthritis. Joints are places where two bones meet, such as your elbow or knee.
The full article covers:
- What is arthritis?
- What are the types of arthritis?
- What are the symptoms of arthritis?
- Who is more likely to get arthritis?
- How is arthritis diagnosed?
- What are the treatments for arthritis?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert M06.4 to ICD-9-CMHistory
Code HistoryHistory
Questions About M06.4Overview
Is M06.4 (Other rheumatoid arthritis) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report inflammatory polyarthropathy on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does M06.4 group to?
When inflammatory polyarthropathy is the principal diagnosis on an inpatient stay, it groups to MS-DRG 553, 554, with relative weights from 0.8301 to 1.2963 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of M06.4?
Under the General Equivalence Mappings, inflammatory polyarthropathy converts to ICD-9-CM 714.89 (inflamm polyarthrop NEC) and 714.9 (inflamm polyarthrop NOS). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:
- The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
- The condition places limitations on self-care, independent living, and social interactions.
