M05.A
ICD-10BillableAbn rheu fctr & anti-citrul protein antibody w rheu arthrit
Official ICD-10-CM descriptor (FY2026)
Abnormal rheumatoid factor and anti-citrullinated protein antibody with rheumatoid arthritis
M05.A is valid for submission on a claim — CMS flags it as a billable, specific code.
Code first
Sequence the underlying condition before this code.
- rheumatoid arthritis with rheumatoid factor by site, if known (M05.00 to M05.8A)
Related codes in M05
- M05.0Felty's syndromecategory
- M05.1Rheumatoid lung disease with rheumatoid arthritiscategory
- M05.2Rheumatoid vasculitis with rheumatoid arthritiscategory
- M05.3Rheumatoid heart disease with rheumatoid arthritiscategory
- M05.4Rheumatoid myopathy with rheumatoid arthritiscategory
- M05.5Rheumatoid polyneuropathy with rheumatoid arthritiscategory
- M05.6Rheumatoid arthritis w involvement of oth organs and systemscategory
- M05.7Rheumatoid arthritis w rheumatoid factor w/o org/sys involvcategory
- M05.8Other rheumatoid arthritis with rheumatoid factorcategory
- M05.9Rheumatoid arthritis with rheumatoid factor, unspecified
Where this code sits
- Parent code
- M05
Krasyn AI Coder
Get code suggestions automatically as you type notes. Free for 50 analyses.
Install for Chrome — freeSource
ICD-10-CM FY2026. Centers for Medicare & Medicaid Services (CMS) / National Center for Health Statistics (NCHS), “2026 ICD-10-CM Code Descriptions in Tabular Order” (icd10cm_order_2026.txt). Download the original file from cms.gov. Public domain (US Government work). Descriptors, billable flags and instructional notes on this page are reproduced from that file without modification. Krasyn adds no clinical guidance.