3.4 Predictive value of serum ferritin and number of red cell
transfusions for abnormal LIC
A serum ferritin exceeding 500 ng/ml had a sensitivity of 80% and
specificity of 79% to predict an elevated LIC. Serum ferritin exceeding
1000 ng/ml uniformly predicted elevated LIC in all the patients
(specificity: 100%); however, the sensitivity dropped to 25%. A
cut-off of 8 units of red cells predicted an elevated LIC with a
sensitivity of 95% and specificity of 49.8%.