To study the level of serum transferrin receptor (sTfR) in children with different stages of iron deficiency, as well as in the normal children, to observe its response to iron supplementation, and to explore the role of sTfR in surveillance of iron status and assessment of iron supplementation in population.
By determining iron status index, 1,006 children aged 6-14 years in Fangshan District, Beijing were divided into four groups, control group, iron depletion (ID) group, iron deficiency erythropoiesis (IDE) group and iron deficiency anemia (IDA) group, and 239 of them were measured for sTfR with Quintikine enzyme immunoassay (R&D system, Minneapolis, MN) and sTfR/logserum ferratin (SF) was estimated. Iron supplementation (NaFeEDTA capsules, containing 60 mg iron element per capsule) was administered for the children with ID and IDE per capsule once weekly and for the children with IDA per capsule thrice weekly for nine weeks. Iron status index and sTfR were measured before and after iron supplementation.
The levels of sTfR and sTfR/log SF in children with ID, IDE and IDA were (20.03 +/- 2.33) nmol/L, (24.52 +/- 1.07) nmol/L, (33.28 +/- 6.09) nmol/L and (18.15 +/- 5.31), (20.98 +/- 8.88), (29.08 +/- 8.57), respectively, significantly higher than those in the control group [sTfR(18.74 +/- 3.06) nmol/L and sTfR/log SF(9.89 +/- 1.74)]. Statistical analysis showed that sTfR correlated to free erythrocyte protoporphyrin and hemoglobin. sTfR levels in normal children was (12.5-23.5) nmol/L. After iron supplementation, sTfR levels in children with ID was (16.37 +/- 3.10) nmol/L, significantly decreased than those before iron supplementation, but no change in sTfR was observed in children with IDE and IDA. sTfR/log SF were decreased significantly in all children with ID group(11.42 +/- 3.12), IDE (16.54 +/- 4.70) and IDA (23.59 +/- 9.93).
sTfR is a specific indicator for identifying IDE and IDA, and sTfR/log SF is a sensitive index for assessing the effects of iron supplementation.