Three patients who developed moderate ALT increase followed by chronic liver dysfunction. Levels of ALT (U/L, dotted line) are plotted against the date of determination. The upper reference limit for ALT was 40 U/L. The results of HGV RNA determination, performed at the beginning and at the end of follow-up, are also reported. These patients had a higher increase of serum ferritin levels than those who maintained normal aminotransferase values (difference of ferritin concentration between follow-up and baseline sample, 1,850 ± 368 ng/mL v 111 ± 814 ng /mL).