A 60-year-old male with newly diagnosed acute myeloid leukemia is admitted for induction chemotherapy. Twenty-four hours after starting chemotherapy, his labs show potassium 6.2 mEq/L, phosphorus 6.0 mg/dL, calcium 7.2 mg/dL, and uric acid 12 mg/dL. He has oliguria. What is the most appropriate initial management step?

✓ Correct Answer: Option B

This patient presents with tumor lysis syndrome (TLS), characterized by hyperkalemia, hyperphosphatemia, hypocalcemia, and hyperuricemia, leading to AKI. Aggressive IV fluids help prevent renal injury, and rasburicase (or allopurinol) rapidly lowers uric acid. Other options address individual electrolyte abnormalities but not the overall TLS management.