Serum ferritin in haemochromatosis: changes in the isoferritin composition during venesection therapy.

The isoferritin composition of serum ferritin in 13 patients with untreated idiopathic haemochromatosis (IHC) has been shown to differ from normal in exhibiting an increase in isoferritins in the pH range 5.54-5.62. A similar change was observed in four patients with gross iron overload secondary to haemolytic anaemia. During the course of venesection therapy there was a progressive rise in isoferritins of pI 5.02-5.06 relative to the more basic isoferritins. These observations are consistent with previous studies showing alterations in tissue isoferritins in untreated IHC before and after venesection therapy and they are compatible with the hypothesis that the more basic isoferritins correspond to a 'storage' ferritin and the more acidic to a 'secretory' ferritin. The studies also provide further evidence for a possible biological role of the individual isoferritins.