William Aird/X
Sep 2, 2025, 08:49
Why Polycythemia Vera Doesn’t Raise EPO Levels Explained by William Aird
William Aird, Professor of Medicine at Harvard Medical School, shared a post on X:
“Why PV Does Not Increase EPO
In PV, renal O2-sensing cells sit in a high-flow, low-extraction zone. Extra O₂ content outweighs modest viscosity effects, so HIF stays off & EPO stays low. The ‘falling off the curve’ in DO₂ vs Hct doesn’t hit them, unless Hct gets extremely high.”

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