Felty's syndrome, right knee

This code indicates Felty's syndrome, a rare and severe complication of rheumatoid arthritis characterized by the triad of seropositive rheumatoid arthritis, splenomegaly, and neutropenia, specifically affecting the right knee. Patients typically present with chronic, erosive arthritis, recurrent infections due to low neutrophil counts, and an enlarged spleen.

Use this code when documentation clearly states a diagnosis of Felty's syndrome with involvement of the right knee. This code is appropriate when the patient's medical record confirms the presence of rheumatoid arthritis, splenomegaly, and neutropenia, and the right knee is identified as an affected joint.

• Ensure documentation specifies "Felty's syndrome" and not just severe rheumatoid arthritis.
• Verify laterality (right knee) is clearly documented; do not assume.
• Code any associated manifestations of rheumatoid arthritis or neutropenia separately, if applicable.