Iron overload may develop in a number of different organs, leading to significant morbidity and mortality. Iron depletion by phlebotomy or chelation can mobilize excess body iron stores and improve outcomes. Therefore, detection and quantitation of iron overload is of vital clinical importance. The liver is the primary storage site for iron in the body and the degree of hepatic iron loading is thought to reflect body iron stores. At present, biochemical measurement of hepatic iron concentration (HIC) is considered the most sensitive method for clinical assessment of iron overload. However, this method has significant limitations because of the need for an invasive liver biopsy procedure and sampling error due to intra-hepatic variability in HIC. These limitations of needle liver biopsy measurements have necessitated the development of alternative, non-invasive and more reliable methods for HIC measurement. This study will assess a new, low-cost, portable device for noninvasively measuring iron concentrations in the liver. The new instrument, is a magnetic susceptometer based on simple, room-temperature magnetic sensors. In previous tests, liver iron values from the new susceptometer correlated well (r=0.98) with those from an existing """"""""SQUID"""""""" susceptometer based on superconducting sensors cooled by liquid helium, although there was no direct comparison with biochemical iron concentrations from tissue samples. The goal of this cross-sectional, cohort study, is to validate the room temperature susceptometer as a clinical tool, by studying patients with iron overload associated with hereditary hemochromatosis, hepatitis C infection or nonalcoholic steatohepatitis. Biochemical iron measurements from a liver biopsy specimen will be compared to the suseptometer values obtained from the same lobe of the liver. These patient populations will test the utility of the room temperature susceptometer in measuring liver iron in patients with a wide range of HIC and variability of iron distribution due to degree of fibrosis and cirrhosis.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Exploratory/Developmental Grants (R21)
Project #
7R21DK072360-03
Application #
7526275
Study Section
Special Emphasis Panel (ZRG1-DIG-C (51))
Program Officer
Doo, Edward
Project Start
2005-09-15
Project End
2011-02-28
Budget Start
2007-07-01
Budget End
2011-02-28
Support Year
3
Fiscal Year
2006
Total Cost
$141,038
Indirect Cost
Name
Benaroya Research Institute at Virginia Mason
Department
Type
DUNS #
076647908
City
Seattle
State
WA
Country
United States
Zip Code
98101
Maliken, Bryan D; Avrin, William F; Nelson, James E et al. (2012) Room-temperature susceptometry predicts biopsy-determined hepatic iron in patients with elevated serum ferritin. Ann Hepatol 11:77-84