Rheu arthritis of left knee w involv of organs and systems

This code signifies rheumatoid arthritis affecting the left knee, where the disease process has extended beyond the joints to involve other organ systems. This systemic involvement can manifest in various ways, such as vasculitis, pulmonary fibrosis, or pericarditis, in addition to the characteristic joint inflammation.

Apply this code when documentation clearly indicates a diagnosis of rheumatoid arthritis with specific involvement of the left knee and evidence of extra-articular manifestations. This requires physician documentation detailing both the joint involvement and the specific other organ or system affected by the rheumatoid disease process.

• Ensure documentation specifies "left" knee involvement; laterality is crucial.
• Verify that the medical record explicitly states involvement of "other organs and systems" beyond the joints.
• Do not use this code if only joint involvement is documented; consider codes for rheumatoid arthritis without systemic involvement.