AN ASSESSMENT OF DRIED BLOOD-SPOT TECHNOLOGY FOR IDENTIFYING IRON-DEFICIENCY

The present study was undertaken to assess the feasibility of using fe rritin and transferrin receptor measurements on dried capillary blood spots to identify iron deficiency (ID) in public health surveys. Measu rements on serum and blood spots prepared from venous blood were perfo rmed in 71 healthy subjects, 41 of whom were iron-replete and 30 who h ad ID, either without (n = 20) or with (n = 10) anemia. parallel measu rements were performed on hemolyzed whole blood and washed hemolyzed r ed blood cells to assess the erythrocyte contribution of ferritin and transferrin receptor to dried blood samples. The concentration of ferr itin in dried blood samples was threefold higher than serum assays due to the release of ferritin from hemolyzed erythrocytes, which diminis hed the usefulness of ferritin measurements for detecting ID. On the o ther hand, there was negligible erythrocyte contribution to the measur ement of transferrin receptor in dried blood spots. The most sensitive parameter in dried blood spots was the ratio of receptor/ferritin, wh ich was suitable for identifying iron-deficiency anemia (IDA), but les s reliable than serum assays for detecting milder ID without anemia. W e conclude that tandem measurements of serum ferritin and transferrin receptor in dried blood spots can be used to facilitate the identifica tion of IDA in epidemiologic studies. (C) 1998 by The American Society of Hematology.