Correlation of serum ferritin with other tests of iron status in sickle cell disease.

The iron status of 42 patients with homozygous SS disease, none of whom was on chronic transfusion therapy, was investigated using tests for serum ferritin, serum iron, serum transferrin, transferrin saturation, and free erythrocyte protoporphyrin. Correlation coefficients were computed between ferritins and the other test results. The mean ferritin level of the group as a whole showed significant inverse linear correlation with the mean transferrin and free erythrocyte protoporphyrin values. The mean ferritin of the subgroup with normal ferritin levels correlated significantly only with the mean free erythrocyte protoporphyrin value. The mean ferritin of the subgroup with high ferritin levels correlated significantly only with the mean transferrin value. In these patients who had received only sporadic blood transfusions, there was poor correlation of ferritin levels with age and number of transfusions.