M00.879 Arthritis due to other bacteria, unspecified ankle and foot

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Applies from M00 Pyogenic arthritis

Excludes2 (not included here)

• infection and inflammatory reaction due to internal joint prosthesis (T84.5-)

Applies from M00.8 Arthritis and polyarthritis due to other bacteria

Use additional code

• code (B96) to identify bacteria

Applies from M00.87 Arthritis due to other bacteria, ankle and foot

Applicable to

• Arthritis due to other bacteria, tarsus, metatarsus, and phalanges

Risk adjustment (HCC)

• CMS-HCC V28: HCC 92 — Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis
• CMS-HCC V22: HCC 39 — Bone/Joint/Muscle Infections/Necrosis
• ESRD V24: HCC 39

MS-DRG index

Defines the logic of DRG(s) 548-550 in MDC 08.

Approximate ICD-9-CM (GEMs)

• 041.89 Other specified bacterial infections in conditions classified elsewhere and of unspecified site, other specified bacteria (approximate)
• 711.07 Pyogenic arthritis, ankle and foot (approximate)
• 711.07 Pyogenic arthritis, ankle and foot (approximate)

Medicare Code Edits (MCE v43.1 (April 2026))

• Unspecified code (laterality): Unspecified codes for which a more specific code identifying laterality (right, left, bilateral) exists within the same code family.

Nearby codes

• M00.862 Arthritis due to other bacteria, left knee
• M00.869 Arthritis due to other bacteria, unspecified knee
• M00.87 Arthritis due to other bacteria, ankle and foot
• M00.871 Arthritis due to other bacteria, right ankle and foot
• M00.872 Arthritis due to other bacteria, left ankle and foot
• M00.879 Arthritis due to other bacteria, unspecified ankle and foot (this code)
• M00.88 Arthritis due to other bacteria, vertebrae
• M00.89 Polyarthritis due to other bacteria
• M00.9 Pyogenic arthritis, unspecified