A 58-year-old man with a diagnosis of chronic myeloid leukemia is treated with intensive chemotherapy. He goes into remission but develops pain in the left wrist. On physical examination, there is swelling and warmth on the palpation of the wrist. Polarized light microscopy of fluid aspirated from the wrist joint shows needle-shaped crystals that display negative birefringence. Which of the following processes most likely played an important role in the pathogenesis of the patient's wrist pain?
High-Yield Explanation
Secondary gout can occur in patients with leukemia, especially patients with a high leukocyte count (as occurs in chronic myeloid leukemia), who are treated with chemotherapeutic agents causing massive lysis of leukemic cell nuclei, and large amounts of urate are produced. The hyperuricemia leads to the deposition of crystals in the joint space that triggers a local inflammatory response. Joint hemorrhages might be seen in patients with thrombocytopenia, but they more typically occur in patients with hemophilia, and neither induces needle-shaped crystal formation. Rhomboid cholesterol crystals are the most likely product of blood breakdown. Articular cartilage damage can be seen in any form of chronic arthritis but is a prominent feature of osteoarthritis, not chemotherapy. Synovial proliferation also is a nonspecific change that is prominent in the inflammation of rheumatoid arthritis, not leukemia. Leukemic cells may infiltrate a variety of visceral organs, but usually not soft tissues.