Studies on the Serum Iron-binding Capacity.

The total iron-binding capacity of serum has been estimated using a colorimetric method, a radioisotopic technique, and a method employing immunodiffusion. The modified isotopic technique described was considered to be the method of choice. The total iron-binding capacity starts to increase at an early stage of an iron-deficiency anaemia. It is decreased in infectious and malignant disease. Close correlation exists between the level of saturation of the total iron-binding capacity and the haemoglobin level in patients with uncomplicated iron-deficiency anaemia. In patients with disease of the liver a difference was sometimes found between the total iron-binding capacity determined by the immunodiffusion method and by the two other techniques, the values with the immunodiffusion method being distinctly lower. This suggests the presence in the serum of iron which is not bound to transferrin. It is possible that ferritin was present in the serum in these cases.