ICD-10 Code M05.59 – Rheumatoid polyneuropathy with rheumatoid arthritis of multiple sites (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M05.59 – Rheumatoid polyneuropathy with rheumatoid arthritis of multiple sites
What it is
This code identifies rheumatoid arthritis affecting multiple sites with associated polyneuropathy. It means the arthritis and nerve involvement are both documented, and you should code the combined condition.
Clinical signs
Clinical features vary; refer to documentation. Typical findings may include rheumatoid joint inflammation plus peripheral nerve symptoms such as numbness, tingling, weakness, or reduced sensation in more than one nerve distribution.
When to use this code
Use M05.59 when the provider clearly documents rheumatoid arthritis of multiple sites with rheumatoid polyneuropathy. This is appropriate when the neuropathy is linked to the rheumatoid disease, not listed as an unrelated condition.
If the record shows rheumatoid arthritis but does not confirm neuropathy, or neuropathy is present without a rheumatoid link, check documentation before coding. Confirm that multiple sites are involved as documented by the provider.
Do not use for
Do not use this code for rheumatoid arthritis without nerve involvement, or for neuropathy from another cause. If the chart does not support the rheumatoid association, check documentation.
Coding tip
Code this only when both rheumatoid arthritis and polyneuropathy are explicitly documented together in the same encounter record.