Hepatic iron concentration and total body iron stores in thalassemia major.

Background and Methods: We tested the usefulness of measuring the hepatic i ron concentration to evaluate total body iron stores in patients who had be en cured of thalassemia major by bone marrow transplantation and who were u ndergoing phlebotomy treatment to remove excess iron. Results: We began treatment with phlebotomy a mean (+/-SD) of 4.3+/-2.7 yea rs after transplantation in 48 patients without hepatic cirrhosis. In the g roup of 25 patients with liver-biopsy samples that were at least 1.0 mg in dry weight, there was a significant correlation between the decrease in the hepatic iron concentration and total body iron stores (r=0.98, P<0.001). A ssuming that the hepatic iron concentration is reduced to zero with complet e removal of body iron stores during phlebotomy, the amount of total body i ron stores (in milligrams per kilogram of body weight) is equivalent to 10. 6 times the hepatic iron concentration (in milligrams per gram of liver, dr y weight). With the use of this equation, we could reliably estimate total body iron stores as high as 250 mg per kilogram of body weight, with a stan dard error of less than 7.9. Conclusions: The hepatic iron concentration is a reliable indicator of tota l body iron stores in patients with thalassemia major. In patients with tra nsfusion-related iron overload, repeated determinations of the hepatic iron concentration can provide a quantitative means of measuring the long-term iron balance. (N Engl J Med 2000;343:327-31.) (C) 2000, Massachusetts Medic al Society.