Clinical usefulness of mean corpuscular volume and red cell distribution width in iron deficient blood donors

The clinical efficacy of the red cell distribution width (RDW > 14.2%) and the mean corpuscular volume (MCV < 83.5 fL) in detecting iron deficiency was evaluated in female blood donors. Employing transferrin saturation < 17%, the prevalence of iron deficiency in 296 female donors was 23%, and in 635 male donors 1.1%. In the total female population, the sensitivity and specificity of the indices were 78% and 92%, respectively, but they were higher in anemic females (sensitivity 90% and positive predictive value 92%) than in non anemic females (sensitivity 58% and positive predictive value 50%). Our results confirm that there is an overlap in the levels of RDW and MCV between the iron and non iron deficient subjects, and these overlap seems to be more remarkable in the non anemic individuals. We conclude that these erythrocyte indices could be useful to identify iron deficiency in anemic female blood donors, but not in non anemic ones.