A study of the mechanisms and sites of action of desferrioxamine in thalassaemia major.

The effects of slow subcutaneous (s.c.) infusions of desferrioxamine (Desferal: DF) on iron metabolism and excretion were studied in 6 thalassaemia major patients in the course of a ferrokinetic study with 59Fe as a label; s.c. DF infusions were performed every 4th day starting 4 days after that of the 59Fe injection. Serum iron and total iron binding capacity (TIBC) increased after s.c. infusion, whereas serum ferritin levels remained unchanged. 59Fe urinary specific activity decreased in all subjects from the first to subsequent infusions, whereas faecal specific activity remained almost constant throughout the experiment. These data support the hypothesis that iron reaching RE cells concentrates initially in a readily chelatable pool from which then it moves to a larger and not readily chelatable pool, whereas iron reaching parenchymal hepatic cells remains permanently available to chelant.