Assessment of liver iron content in 271 patients: a reevaluation of direct and indirect methods.
Two direct methods for hepatic iron assessment (liver iron concentration and stainable liver iron--judged by a new histologic grading) and three indirect methods (serum iron and transferrin saturation, deferoxamine-chelation test, and ferritinemia) were reevaluated in 271 patients. These patients consisted of: 103 with idiopathic hemochromatosis, 39 with alcoholic cirrhosis, 54 with noncirrhotic alcoholic liver diseases, 13 with nonalcoholic liver diseases, and 62 with miscellaneous disorders. The results indicate that: (a) liver iron concentration, well correlated with mobilized excess iron (r = 0.88; p < 0.01), is the method of reference and validates the proposed histologic grading; (b) serum ferritin, which is in good correlation with liver iron concentration (r = 0.80; p < 0.01), is a valuable indirect method for hepatic iron evaluation; (c) regarding the other indirect methods a "boundary zone" may be delimited, thus corresponding to liver iron concentration values of 10.7 mumol/100 mg dry liver weight, beyond which values of serum iron less than 28.6 micrometer or transferrin saturation less than 45% or chelatable iron less than 45 mumol/24 h are rare; and (d) using the various indirect methods, there is a marked risk in idiopathic hemochromatosis to underestimate and in alcoholic liver diseases to overestimate hepatic iron content.