Postdysenteric arthropathy, unspecified knee

This code describes joint inflammation in an unspecified knee that develops after a bout of dysentery. It represents a reactive arthritis, meaning the joint inflammation is triggered by an infection elsewhere in the body, in this case, the gastrointestinal tract. The arthropathy is non-suppurative and typically aseptic.

Use this code when documentation clearly indicates a diagnosis of reactive arthritis affecting the knee, with a direct causal link to a preceding dysenteric infection. This diagnosis is often made after ruling out other causes of arthritis and identifying a history of dysentery. Supporting documentation should include a history of dysentery and clinical findings consistent with arthropathy of the knee.

• Ensure documentation specifies the knee as the affected joint; if another joint is involved, a more specific code should be used.
• This code is for an unspecified knee; if laterality (right or left) is documented, a more specific code (M02.161 or M02.162) should be assigned.
• Do not confuse with other forms of reactive arthritis or infectious arthritis where the joint itself is infected.