Rasburicase is planned for rapid lowering of serum urate before chemotherapy in a patient with tumour lysis syndrome. Screening for which condition is essential before giving the first dose?

• A Urate oxidase autoantibodies
• B Hereditary fructose intolerance
• C Methylenetetrahydrofolate reductase polymorphism
• D Glucose-6-phosphate dehydrogenase deficiency ✓

Explanation

Rasburicase is a recombinant urate oxidase that converts urate to allantoin. Its reaction generates hydrogen peroxide, and in glucose-6-phosphate dehydrogenase deficiency the resulting oxidative stress causes haemolysis and methaemoglobinaemia. G6PD status must be checked before use, and the drug is contraindicated in deficient patients. Pegloticase carries the same caution, while allopurinol and febuxostat are enzyme inhibitors and carry no such risk.

Reference: Goodman and Gilman's The Pharmacological Basis of Therapeutics, 14th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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