RDW
Background
- Red cell distribution width; measure of variation in red blood cell size (anisocytosis)
Normal Values
- Normal: 11.5-14.5%
Interpretation
- Elevated RDW indicates variation in RBC sizes (anisocytosis)
- Useful in distinguishing iron deficiency anemia (elevated RDW) from thalassemia trait (normal RDW)
- Elevated in mixed-deficiency anemias, early iron/B12/folate deficiency, and transfused patients
- Elevated RDW has been studied as a prognostic marker in heart failure, PE, and sepsis