Utility of hepatic iron index in American patients with hereditary hemochromatosis: A multicenter study

Background & Aims: A hepatic iron index (hepatic iron concentration divided by age) of move than 1.9 has been proposed as useful to identify patients with homozygous hereditary hemochromatosis (HHC). There are limited data on the diagnostic use of the hepatic iron index in patients with HHC in the United States, This study evaluated the hepatic iron index in the diagnosis of HHC in a multicenter U.S. study. Methods: Hepatic iron concentration was measured in 509 patients undergoing liver biopsy, The diagnosis of HHC was made using clinical, biochemical, and histopathologic criteria. Results: Fifty-five patients met criteria for HHC; hepatic iron index was >1.9 in 51 of 55 (93%) patients with HHC but in none of 454 patients with other liver diseases; hepatic iron concentration was >71 mu mol/g dry weight in 54 of 55 patients with HHC but only 1 of the other 454 patients. Conclusions: A hepatic iron index of greater than or equal to 1.9 can identify most U.S. patients with HHC but is less than or equal to 1.9 in 7%. A ''threshold'' hepatic iron concentration of 71 mu mol/g can almost always distinguish patients with HHC from patients with other liver diseases and may be a useful adjunct to the hepatic iron index in the diagnosis of HHC in the diverse U.S. population.