Evaluation of red cell distribution width in the diagnosis of iron deficiency anemia

Anuja Sharma, Mahima Sharma, Vandana Sharma


Background: Iron deficiency anemia is the most common nutritional deficiency world over and in India. It is the most important cause of microcytic hypochromic anemia. Red cell distribution width (RDW) provides quantitative assessment of anisocytosis and could be helpful in differentiating iron deficiency anemia from other microcytic anemias. The objective behind this study was to assess the role of RDW as an early indicator in diagnosing iron deficiency anemia.

Methods: A total of 100 cases of microcytic anemia (MCV <80fl) were included in the study. RDW values were obtained on an automated hematology analyser. Sensitivity, specificity, positive predictive value, negative predictive value of RDW in iron deficiency anemia were studied.

Results: With cut off value of 14.5%, sensitivity and specificity of RDW as a test in diagnosis of iron deficiency anemia were 84.81% and 57.14% respectively and a positive and negative predictive value of 88.15% and 50% respectively.

Conclusions: RDW has a high sensitivity and can be used as a simple, economical, reliable automated red blood cell parameter for initial diagnosis of iron deficiency anemia.


Red cell distribution width, Iron deficiency anemia, Microcytic hypochromic anemia

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