A patient with suspected Wilson's disease has serum ceruloplasmin of 0.08 g/L (normal 0.2–0.6 g/L). Which enzyme activity provides a DIRECT functional assessment of copper status in this context?
- A Superoxide dismutase (Cu/Zn-SOD) activity in erythrocytes ✓
- B Ceruloplasmin ferroxidase activity
- C Serum lysyl oxidase activity
- D Monoamine oxidase activity
Correct answer: A. Superoxide dismutase (Cu/Zn-SOD) activity in erythrocytes
Explanation
Erythrocyte Cu/Zn-superoxide dismutase (SOD1) requires copper as a cofactor; its activity directly reflects intracellular copper availability and is used as a functional biomarker of copper status. Ceruloplasmin is a transport protein that can be falsely elevated by inflammation. Lysyl oxidase requires copper but is not routinely measured clinically for copper status in Wilson's disease assessment.
Reference: Harper's Illustrated Biochemistry, 32nd ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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