RDW
Medical abbreviation · Laboratory Test
| Stands for | Red cell distribution width |
|---|---|
| Categories | Medical |
RDW stands for Red cell distribution width, a laboratory test abbreviation.
Measures variation in red blood cell size (anisocytosis), usually reported as a coefficient of variation with a reference range around 11.5 to 14.5 percent. A high RDW indicates a mixed population of cell sizes, as seen in early iron deficiency, after transfusion or with combined nutritional deficiencies.
Example: Iron studies were sent because RDW was 17.2% despite a normal MCV.
Usage notes
Helpful for separating iron deficiency (high RDW) from thalassemia trait (usually normal RDW) when both produce small cells. Some analyzers also report an RDW-SD value in femtoliters. Large population studies have linked a raised RDW to higher mortality in heart failure and other chronic illnesses, although it is not used on its own for prognosis.
Related abbreviations
More laboratory test abbreviations
- PT – Prothrombin time
- PT/INR – Prothrombin time with international normalized ratio
- PTT – Partial thromboplastin time
- QNS – Quantity not sufficient
- RADT – Rapid antigen detection test
- RBC – Red blood cell count
- Retic – Reticulocyte count
- RF – Rheumatoid factor
- RFP – Renal function panel
- Rh – Rhesus (D antigen)
- RI – Reference interval
- RPR – Rapid plasma reagin
See all 135 laboratory test abbreviations →
This entry is for general education and is not medical advice. Abbreviation use varies between institutions; always confirm in context.