Severity of iron overload in patients with sickle cell disease receiving chronic red blood cell transfusion therapy

Chronic transfusion therapy is being used more frequently to prevent and tr eat the complications of sickle cell disease. Previous studies have shown t hat the iron overload that results from such therapy in other patient popul ations is associated with significant morbidity and mortality. In this stud y we examined the extent of iron overload as well as the presence of liver injury and the predictive value of ferritin in estimating iron overload in children with sickle cell disease who receive chronic red blood cell transf usions. A poor correlation was observed between serum ferritin and the quan titative iron on liver biopsy (mean 13.68 +/- 6.64 mg/g dry weight; R = 0.3 50, P = .142). Quantitative iron was highly correlated with the months of t ransfusion (R = 0.795, P < .001), but serum ferritin at biopsy did not corr elate with months of transfusion (R = 0.308, P = .200). Sixteen patients ha d abnormal biopsies showing mild to moderate changes on evaluation of infla mmation or fibrosis. Liver iron was correlated with fibrosis score (R = 0.5 0, P = .042). No complications were associated with the liver biopsy. Our d ata suggest that, in patients with sickle cell disease, ferritin is a poor marker for accurately assessing iron overload and should not be used to dir ect long-term chelation therapy. Despite high levels of liver iron, the ass ociated liver injury was not severe. (Blood. 2000;96:76-79) (C) 2000 by The American Society of Hematology.