M00.861 – Arthritis due to other bacteria, right knee

ICD-10-CM 2027 diagnosis code · Infectious arthropathies

Billable code

ICD-10-CM code M00.861

Code: M00.861 (claims format: M00861)
Description: Arthritis due to other bacteria, right knee
Billable: Yes – valid for HIPAA-covered transactions
Valid for: Dates of service October 1, 2026 – September 30, 2027 (FY2027)
Chapter: 13. Diseases of the musculoskeletal system and connective tissue (M00-M99)
Block: M00-M02 Infectious arthropathies
Parent codes: M00 › M00.8 › M00.86

Notes inherited from parent codes

Instructional notes at a category or block level apply to every code below it.

M00 – Pyogenic arthritis

Excludes2 (not included here):

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

M00.8 – Arthritis and polyarthritis due to other bacteria

Use additional code:

code (B96) to identify bacteria

Block M00-M02

Notes:

This block comprises arthropathies due to microbiological agents. Distinction is made between the following types of etiological relationship:
a) direct infection of joint, where organisms invade synovial tissue and microbial antigen is present in the joint;
b) indirect infection, which may be of two types: a reactive arthropathy, where microbial infection of the body is established but neither organisms nor antigens can be identified in the joint, and a postinfective arthropathy, where microbial antigen is present but recovery of an organism is inconstant and evidence of local multiplication is lacking.

Related codes in M00.86

Frequently asked questions

What is ICD-10 code M00.861?

M00.861 is the ICD-10-CM code for arthritis due to other bacteria, right knee, in the block M00-M02 (Infectious arthropathies).

Is M00.861 a billable code?

Yes. M00.861 is a billable/specific code that can be used to indicate a diagnosis for reimbursement purposes.

What category does M00.861 belong to?

It belongs to category M00 – Pyogenic arthritis.

Source: CDC/NCHS ICD-10-CM FY2027 code files, tabular list and index. Reference only – code assignment must follow the official ICD-10-CM guidelines and documentation in the medical record.