The use of skin Fe levels as a surrogate marker for organ Fe levels, to monitor treatment in cases of iron overload

A system based on the detection of K-shell x-ray fluorescence (XRF) has bee n used to investigate whether a correlation exists between the concentratio n of iron in the skin and the concentration of iron in the liver, as the de gree of iron loading increases. The motivation behind this work is to devel op a non-invasive method of determining the extent of the body's iron store s via measurements on the skin, in order to monitor the efficacy of chelati on therapy administered to patients with beta-thalassaemia. Sprague-Dawley rats were iron loaded via injections of iron dextran and subsequently treat ed with the iron chelator CP94. The non-haem iron concentrations of the liv er, heart and spleen were determined using bathophenanthroline sulphonate a s the chromogen reagent. Samples of abdominal skin were taken and the iron concentrations determined using XRF A strong correlation between the skin i ron concentration and the liver iron concentration has been demonstrated (R -2 = 0.86). Similar correlations exist for the heart and the spleen. These results show that this method holds great potential as a tool in the diagno sis and treatment of hereditary haemachromatosis and beta-thalassaemia.