A Clinical Evaluation of Serum Ferritin as an Index of Iron Stores

Abstract

Measurements of serum ferritin were correlated with other hematologic laboratory indexes in 250 hospitalized subjects with anemia or disorders in iron metabolism. A geometric mean value of 4 ng per milliliter was found in 32 patients with uncomplicated iron-deficiency anemia, and one of 2930 ng per milliliter in 23 with iron overload. Among subjects with anemia from causes otherthan iron deficiency, the mean serum ferritin level was increased to 180 ng per milliliter (geometric mean in normal controls, 59 ng per milliliter, with a 95 per cent confidence range of 12 to 300 ng per milliliter), presumably reflecting the transport of red-cell iron to stores. The wide range of values found was shown to be related primarily to the magnitude of body iron stores in each case as evaluated by bone-marrow hemosiderin. In addition, however, inflammation, liver disease and increased red-cell turnover were shown to elevate the serum ferritin concentration to a degree disproportionate to that of iron stores. (N Engl J Med 290:1213–1216, 1974)