Brewin et al reported the ratio of soluble transferrin receptor to absolute reticulocyte count in patients with sickle cell disease. This may reflect the degree of ineffective erythropoiesis. The authors are from King's College London and King's College Hospital.
Patient selection: sickle cell disease
Parameters:
(1) soluble transferrin receptor in nmol/L (proportional to the mass of erythropoietic tissue)
(2) absolute reticulocyte count in 10^9/L
index of ineffective erythropoiesis = ratio of the 2 parameters =
= (soluble transferrin receptor) / (absolute reticulocyte count)
Interpretation:
• The upper limit of the normal reference range is 0.28.
• A ratio greater than the upper limit of normal indicates ineffective erythropoiesis.
• A fall in the ratio indicates more effective erythropoiesis.
• The presence of iron deficiency (associated with elevated soluble transferrin receptor) may impact the index.
Correlations:
(1) The genetic ability to synthesize more Hemoglobin F is associated with less ineffective erythropoiesis.
(2) Hydroxyurea increases ineffective erythropoiesis.
(3) Blood transfusion reduces ineffective erythropoiesis.
