Iron overload in patients with TM. Ferritin and hepatic iron concentration are shown as a function of age. Filled circles indicate patients with cirrhosis. No patients younger than 13 years of age who had liver biopsy had evidence of cirrhosis. HIC and ferritin values are on a log scale. (A) Serum ferritin levels within 2 years of registry entry are shown for 330 patients with TM. Values more than 2500 ng/mL (shown by the dashed line) are associated with higher risk of long-term cardiac morbidity and mortality.²  (B) Hepatic iron concentration by biopsy (93%) or magnetic susceptibility (7%) was performed within 2 years of registry entry for 166 TM patients. The dashed horizontal at 15 mg/g dry weight is discussed in the text.