title: Challenges in the diagnosis of iron deficiency in children exposed to high prevalence of infections.
abstract: BACKGROUND
  While WHO guidelines recommend iron supplements to only iron-deficient children in high infection pressure areas, these are rarely implemented. One of the reasons for this is the commonly held view that iron supplementation increases the susceptibility to some infectious diseases including malaria. Secondly, currently used markers to diagnose iron deficiency are also modified by infections. With the objective of improving iron deficiency diagnosis and thus, its management, we evaluated the performance of iron markers in children exposed to high infection pressure.
  
  
  RESULTS
  Iron markers were compared to bone marrow findings in 180 anaemic children attending a rural hospital in southern Mozambique. Eighty percent (144/180) of the children had iron deficiency by bone marrow examination, 88% (155/176) had an inflammatory process, 66% (119/180) had moderate anaemia, 25% (45/180) severe anaemia and 9% (16/180) very severe anaemia. Mean cell haemoglobin concentration had a sensitivity of 51% and specificity of 71% for detecting iron deficiency. Soluble transferrin receptor (sTfR) and soluble transferrin receptor/log ferritin (TfR-F) index (adjusted by C reactive protein) showed the highest areas under the ROC curve (AUC(ROC)) (0.75 and 0.76, respectively), and were the most sensitive markers in detecting iron deficiency (83% and 75%, respectively), but with moderate specificities (50% and 56%, respectively).
  
  
  CONCLUSIONS
  Iron deficiency by bone marrow examination was extremely frequent in these children exposed to high prevalence of infections. However, even the best markers of bone marrow iron deficiency did not identify around a quarter of iron-deficient children. Tough not directly extrapolated to the community, these findings urge for more reliable, affordable and easy to measure iron indicators to reduce the burden of iron deficiency anaemia in resource-poor settings where it is most prevalent.
authors.affiliation: Barcelona Centre for International Heath Research, Hospital Clínic, University of Barcelona, Barcelona, Spain. ruth.aguilar@cresib.cat
authors.forename: Ruth
authors.initials: R
authors.lastname: Aguilar
authors.forename: Cinta
authors.initials: C
authors.lastname: Moraleda
authors.forename: Llorenç
authors.initials: L
authors.lastname: Quintó
authors.forename: Montse
authors.initials: M
authors.lastname: Renom
authors.forename: Lázaro
authors.initials: L
authors.lastname: Mussacate
authors.forename: Eusebio
authors.initials: E
authors.lastname: Macete
authors.forename: Josep L
authors.initials: JL
authors.lastname: Aguilar
authors.forename: Pedro L
authors.initials: PL
authors.lastname: Alonso
authors.forename: Clara
authors.initials: C
authors.lastname: Menéndez
mesh_terms: D018798:Anemia, Iron-Deficiency / Q000175:diagnosis* / Q000378:metabolism; D019540:Area Under Curve; D015415:Biomarkers / Q000378:metabolism; D001856:Bone Marrow Examination; D016022:Case-Control Studies; D002675:Child, Preschool; D005260:Female; D005293:Ferritins / Q000378:metabolism; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009073:Mozambique; D015995:Prevalence; D011990:Receptors, Transferrin / Q000378:metabolism
chemical_list: D015415:Biomarkers; D011990:Receptors, Transferrin; D005293:Ferritins