title: Transient impairment of reticulocyte hemoglobin content and hepcidin-25 induction in patients with community-acquired pneumonia.
abstract: BACKGROUND
  Patients with community-acquired pneumonia (CAP) often exhibit a declining hemoglobin (Hb) concentration. During inflammation pro-inflammatory cytokines and cells of the reticuloendothelial system induce disturbances in iron homeostasis. In this study inflammation markers and hepcidin-25 concentrations were monitored together with short-term alterations in reticulocyte hemoglobinization (RET-He).
  
  
  METHODS
  A total of 25 patients with CAP participated in the study. The assay for serum hepcidin-25 is based on a combination of weak cation exchange chromatography and time-of-flight mass spectrometry.
  
  
  RESULTS
  At hospital admission serum hepcidin-25 concentrations (14.6 ± 6.9 nMol/L, mean ± SD) were established in the upper level of the reference range (0.5-13.9 nMol/L). Results for C-reactive protein (CRP) and Interleukin-6 (IL-6) were obviously increased compared to the reference ranges. From admission until day 14 hepcidin-25, CRP and IL-6 steadily decreased towards the reference ranges. Hb concentrations declined from admission until day 4 from 8.1 ± 1.0 mMol/L to 7.4 ± 0.9 mMol/L. At admission Ret-He results were within the lower region of the reference range (1900-2300aMol) and results demonstrated a decline during admission from 1931 ± 241 aMol until 1845 ± 199 aMol (NS) at day 4. From a minimum Ret-He value at day 4 results increased towards 2129 ± 136 aMol at day14.
  
  
  CONCLUSIONS
  A transient increase of cytokine-stimulated serum hepcidin-25 in combination with a temporary decrease of Hb and Ret-He is demonstrated in patients with CAP. Our results support the hypothesis that hepcidin-25 induces transient impairment of reticulocyte hemoglobin content (Ret-He).
authors.affiliation: Department of Clinical Chemistry, Hematology & Immunology, Medical Center Alkmaar, The Netherlands. m.g.schoorl@mca.nl
authors.forename: Margreet
authors.initials: M
authors.lastname: Schoorl
authors.forename: Dominic
authors.initials: D
authors.lastname: Snijders
authors.forename: Marianne
authors.initials: M
authors.lastname: Schoorl
authors.forename: Wim G
authors.initials: WG
authors.lastname: Boersma
authors.forename: Piet C M
authors.initials: PC
authors.lastname: Bartels
mesh_terms: D023181:Antimicrobial Cationic Peptides / Q000096:biosynthesis*; D015415:Biomarkers; D017714:Community-Acquired Infections / Q000097:blood*; D006454:Hemoglobins / Q000378:metabolism*; D064451:Hepcidins; D006801:Humans; D011014:Pneumonia / Q000097:blood*; D012156:Reticulocytes / Q000378:metabolism*
chemical_list: D023181:Antimicrobial Cationic Peptides; D015415:Biomarkers; D006454:Hemoglobins; D064451:Hepcidins; C545475:hepcidin 25, human