Which agent is used to prevent uric acid nephropathy in tumor lysis syndrome?

Which agent is used to prevent uric acid nephropathy in tumor lysis syndrome?

• A. Rasburicase
• B. Allopurinol
• C. Pemetrexed
• D. Methotrexate

Answer: (B)

Tumor lysis syndrome can flood the kidneys with uric acid from rapidly lysed tumor cells, and uric acid crystals can obstruct tubules leading to nephropathy. To prevent this, you want to reduce uric acid production in the first place. Allopurinol blocks xanthine oxidase, the enzyme that converts purines to uric acid, so less uric acid is formed and the risk of precipitation in the kidneys decreases. Rasburicase lowers uric acid by converting it to allantoin, which is helpful for rapidly reducing high uric acid levels or in high-risk situations, but it’s typically reserved for treatment or specific prophylaxis rather than routine prevention. The other two options are not used to prevent uric acid nephropathy. So, allopurinol is the appropriate preventive choice.

Tumor lysis syndrome can flood the kidneys with uric acid from rapidly lysed tumor cells, and uric acid crystals can obstruct tubules leading to nephropathy. To prevent this, you want to reduce uric acid production in the first place. Allopurinol blocks xanthine oxidase, the enzyme that converts purines to uric acid, so less uric acid is formed and the risk of precipitation in the kidneys decreases. Rasburicase lowers uric acid by converting it to allantoin, which is helpful for rapidly reducing high uric acid levels or in high-risk situations, but it’s typically reserved for treatment or specific prophylaxis rather than routine prevention. The other two options are not used to prevent uric acid nephropathy. So, allopurinol is the appropriate preventive choice.