An 11-year-old boy with Burkitt lymphoma is brought to the emergency department because of nausea, vomiting, flank pain, and dark urine for 1 day. Two days ago, he began induction chemotherapy with cyclophosphamide, vincristine, prednisolone, and doxorubicin. His serum creatinine level is 2.7 mg/dL. Renal biopsy reveals multiple uric acid crystals obstructing renal tubular lumen. The principal site of uric acid precipitation would be which of the following?

Question

An 11-year-old boy with Burkitt lymphoma is brought to the emergency department because of nausea, vomiting, flank pain, and dark urine for 1 day. Two days ago, he began induction chemotherapy with cyclophosphamide, vincristine, prednisolone, and doxorubicin. His serum creatinine level is 2.7 mg/dL.  Renal biopsy reveals multiple uric acid crystals obstructing renal tubular lumen.  The principal site of uric acid precipitation would be which of the following?

Quizplus · Accepted Answer

Eductional Objective: Tumor lysis syndrome occurs when tumors with a high cell turnover are treated with chemotherapy. The lysis of tumor cells causes intracellular ions, such as potassium and phosphorous, and uric acid (metabolite of tumor nucleic acid) to be released into serum. Uric acid is soluble at physiologic pH, but it can precipitate in the normally acidic environment of distal tubules and collecting ducts. The prevention of tumor lysis syndrome includes urine alkalinization and hydration, as high urine flow and high pH along the nephron prevents crystallization and precipitation of uric acid.

An 11-Year-Old Boy with Burkitt Lymphoma Is Brought to the Emergency