title: Serum transferrin receptor, ferritin, and reticulocyte maturity indices during the first year of life in 'large' preterm infants.
abstract: BACKGROUND
  Preterm infants are at risk of developing iron deficiency; among the iron status and hemopoiesis indices the serum transferrin receptor (sTfr) has been shown to be a useful indicator in assessing iron status, while immature reticulocyte production is regarded as an estimator of erythropoiesis.
  
  
  OBJECTIVE
  To investigate age-related changes in iron status infants born 'moderately' preterm, with a gestational age (GA) of 32-36 wk, and identify associations between sTfr and other hematological and biochemical iron indices.
  
  
  METHODS
  Hospital-based prospective, longitudinal study in preterm infants.
  
  
  METHODS
  Iron and erythropoiesis parameters were evaluated in 181 formula-fed preterm infants at 2 and 6 wk and 3, 6, 9, and 12 months chronological age. Hemoglobulin (Hb), hematocrit (Hct), mean corpuscular volume (MCV), reticulocytes, serum iron (sFe), serum ferritin (sFer), sTfr, and reticulocyte subpopulations were measured.
  
  
  RESULTS
  A total of 756 measurements were performed. After an initial decline, Hb rose from month 3 to 12 of life. SFe and sFer and immature reticulocyte count decreased from the second week to the third month and remained stable thereafter. STfr was lower up to 6 wk and stable from month 3 to 12. Iron deficiency anemia (IDA) was found in 5.5% of infants. In 76 measurements sFer was <12 microg/L, implying storage iron deficiency (SID). A negative correlation was observed between sTfr and other indices of iron status such as Hb, Hct, MCV, sFe, and sFer. Infants with sFer <12 microg/L had lower sTfr than those with sFer >12 microg/L. Reticulocyte production was positively associated with STfr, but this association was dependent on the chronological age of the infant.
  
  
  CONCLUSIONS
  Iron depletion is common in formula-fed preterm (32-36 wk GA) infants between month 3 and 12 of life. STfr appears to be an indicator of iron status in preterm infants during the first year of life.
authors.affiliation: Neonatal Intensive Care Unit, Child Health Department, University of Ioannina, Ioannina, Greece.
authors.forename: Vassiliki
authors.initials: V
authors.lastname: Schiza
authors.forename: Vasileios
authors.initials: V
authors.lastname: Giapros
authors.forename: Konstantina
authors.initials: K
authors.lastname: Pantou
authors.forename: Paraskevi
authors.initials: P
authors.lastname: Theocharis
authors.forename: Anna
authors.initials: A
authors.lastname: Challa
authors.forename: Styliani
authors.initials: S
authors.lastname: Andronikou
mesh_terms: D000367:Age Factors; D000375:Aging / Q000097:blood*; D004909:Erythrocyte Indices; D004920:Erythropoiesis; D005260:Female; D005293:Ferritins / Q000097:blood*; D005865:Gestational Age; D006400:Hematocrit; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature / Q000097:blood*; D007501:Iron / Q000097:blood*; D008137:Longitudinal Studies; D008297:Male; D011446:Prospective Studies; D011990:Receptors, Transferrin / Q000097:blood*; D012156:Reticulocytes
chemical_list: D006454:Hemoglobins; D011990:Receptors, Transferrin; D005293:Ferritins; D007501:Iron