THE CLINICAL-SIGNIFICANCE OF SERUM TRANSFERRIN RECEPTOR LEVELS IN SICKLE-CELL DISEASE

Serum transferrin receptor (TfR) levels were measured in 182 children with homozygous sickle cell (SS) disease, 47 with sickle cell-haemoglo bin C (SC) disease and 41 normal (AA) controls on their eighth birthda y. Highly significant elevations occurred in SS compared to SC disease and in SC disease compared to AA controls. Females had higher levels than males in controls but lower levels than males in SS and SC diseas e. In SS disease, serum TfR levels tended to rise with age from 2 to 8 years, the change within individuals correlating with a change in ret iculocyte count (r = 0.38, P = 0.017) and fall in fetal haemoglobin le vels (r = -0.51, P = 0.004). Serum TfR levels did not change with infe ction or painful crisis but were markedly elevated in hypersplenism an d fell following splenectomy in these subjects. In the aplastic crisis , serum TfR levels tended to rise following clinical presentation and then fall, reflecting the reticulocyte counts. These observations are consistent with serum TfR levels being a useful indicator of the degre e of erythropoietic expansion in sickle cell disease.