A 20-year-old man with acute lymphoblastic leukaemia develops severe hyperuricaemia from tumour lysis. Before giving rasburicase, which screening test is mandatory because the drug can trigger life-threatening haemolysis?
- A G6PD deficiency screen ✓
- B Methaemoglobin level
- C HLA-B*15:02 typing
- D Direct Coombs test
Correct answer: A. G6PD deficiency screen
Explanation
Rasburicase converts urate to allantoin via hydrogen peroxide generation. In glucose-6-phosphate dehydrogenase deficiency, red cells cannot regenerate reduced glutathione to detoxify peroxide, causing acute haemolysis and methaemoglobinaemia, so G6PD status must be checked first. The Coombs test is irrelevant because this haemolysis is oxidative and non-immune, which is the fact that rules out option D.
Reference: Katzung Basic and Clinical Pharmacology, 16th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.