Iron absorption, iron loss and iron retention in man: studies after oral administration of a tracer dose of 59FeSO4 and 131-BaSO4.

Abstract

Summary.The absorption of iron administered as ferrosulphate was studied in normal subjects, in patients with iron deficiency and in patients with idiopathic and secondary haemosiderosis. By using a test dose combining radioactive iron (59Fe) with radioactive barium sulphate (131Ba) as inert indicator, it was possible to determine how much iron was initially absorbed and whether a proportion of this was later excreted in the faeces.The (initial) iron absorption, the iron loss as a percentage of the iron absorbed, and the (ultimate) iron retention 2 weeks after administration of the test dose were calculated.In normal subjects and patients with secondary haemosiderosis, a large proportion of the initially absorbed iron later returned to the intestinal lumen. In patients with iron deficiency and those with idiopathic haemosiderosis, however, nearly all the initially absorbed iron was retained in the organism. In differential diagnosis between idiopathic and secondary haemosiderosis, therefore, determination of the iron absorption and iron retention percentages from a test dose may be important.In patients with secondary haemosiderosis there seemed to be a negative correlation between the degree of haemosiderosis and the amount of iron from the test dose ultimately retained in the organism.