USMLE-Rx Step 1 Qmax Challenge #4057

Check out today’s Step 1 Qmax Question Challenge.

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After a night of heavy drinking, a 37-year-old man experiences pain, warmth, swelling, and redness around his big toe, shown radiographically in the image. He had been previously warned against drinking heavily, as it could exacerbate the pain in his toe.

Which of the following enzymes is responsible for the final conversion of the product responsible for this patient’s pain?

A. Adenosine deaminase
B. Cystathionine synthase
C. Hypoxanthine guanine phosphoribosyltransferase
D. Phenylalanine hydroxylase
E. Xanthine oxidase

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