ICD-10 Code M00.179 – Pneumococcal arthritis, unspecified ankle and foot (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M00.179 – Pneumococcal arthritis, unspecified ankle and foot
What it is
This code identifies pneumococcal septic arthritis affecting an unspecified ankle or foot joint. Use it when documentation names Streptococcus pneumoniae as the cause and does not specify the exact ankle or foot joint.
Clinical signs
Typical findings include acute joint pain, swelling, warmth, and reduced range of motion. Fever may occur, and clinical features vary; refer to documentation.
When to use this code
Use M00.179 when the provider documents pneumococcal arthritis in the ankle or foot but does not identify a more specific joint. It also fits cases where the infection is clearly septic arthritis due to pneumococcus and the site remains unspecified. Check documentation if laterality or a more exact joint is recorded.
Do not use for
Do not use this code for noninfectious arthritis, gout, or arthritis caused by another organism. If the record does not confirm pneumococcal involvement, check documentation.
Coding tip
Code the organism and joint site exactly as documented; unspecified joint detail supports this code, but more specific ankle or foot documentation may require another code.