title: [Value of soluble transferrin receptor in the diagnosis of iron deficiency in children].
abstract: OBJECTIVE
  To study the prevalence of iron deficiency in children between 6 months and 7 years and to study the diagnostic value of soluble transferrin receptor (sTfR) for iron deficiency in the children.
  
  
  METHODS
  A total of 502 healthy children between 6 months and 7 years from Hangzhou City of Zhejiang Province were enrolled. Serum sTfR, serum ferritin (SF), serum iron (SI), total iron blinding capacity (TIBC), zinc protoporphyrin (ZPP), Hb, MCV and CRP levels were measured.
  
  
  RESULTS
  The prevalence rate of iron deficiency was 19.5% in children at ages of 6 months to 7 years. The prevalence rate of iron deficiency was the highest in infants (≤1 year old; 34.7%), followed by in toddlers (1-3 years old; 19.4%) and preschoolers (3-7 years old; 14.0%). The mean serum sTfR level in infants (2.02±0.73 mg/L) was significantly higher than that in toddlers (1.68±0.40 mg/L) and preschoolers (1.67±0.29 mg/L) (P<0.05).The best cut-off value of serum sTfR for the diagnosis of iron deficiency was 2.02 mg/L in infants (sensitivity: 70.3%, specificity: 82.2%). The best cut-off value was 1.85 mg/L in toddlers (sensitivity: 71.7%; specificity: 86.4%), and that was 1.85 mg/L in preschoolers (sensitivity: 77.8%; specificity: 88.6%). Serum sTfR was correlated with SF (r=0.107, P<0.05), TIBC (r=0.276, P<0.01), TS (r=-0.139, P<0.05), ZPP (r=0.175, P<0.01) and MCV (r=-0.140, P<0.01).
  
  
  CONCLUSIONS
  Iron deficiency is more prevalent in infants ≤1 year old. The mean serum level and the cut-off value of sTfR in infants are higher than in toddlers and preschoolers. Serum sTfR is an effective index for the diagnosis of iron deficiency in children, especially in infants≤ 1 year old.
authors.affiliation: Department of Child Health Care, Children's Hospital Affiliated to Zhejiang University, Hangzhou 310003, China.
authors.forename: Ya-Ping
authors.initials: YP
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Shao
authors.forename: Xue-Ling
authors.initials: XL
authors.lastname: Zhuang
mesh_terms: D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D000090463:Iron Deficiencies; D008297:Male; D015995:Prevalence; D011990:Receptors, Transferrin / Q000097:blood*
chemical_list: D011990:Receptors, Transferrin