title: Fragmented red cells reference range for the Sysmex XN®-series of automated blood cell counters.
abstract: BACKGROUND
  Fragmented red cells (FRCs) are a new parameter determined automatically by the latest generation of blood cell counters. FRC counts may be of interest as they may reflect schistocyte counts measured on a stained peripheral blood smear observed under the microscope. However, FRC counts depend on the technical procedure used to detect them so that reference ranges are device dependent. The XN-9000® is one of the latest models from the Sysmex series of analysers.
  
  
  RESULTS
  We aimed to establish a reference range for FRCs based on 1366 normal patient samples. The mean ± SD was 0.14 ± 0.35% and the median was 0% (95% confidence interval of the mean: 0.12-0.16%). We observed that the percentage of red blood cells with <17 pg of haemoglobin content (Hypo-He) was correlated to an FRC increase and that flagged results relating to red blood cells, reticulocytes or platelets might have presented with artefactually increased FRCs.
  
  
  CONCLUSIONS
  The FRCs reference range (healthy subjects) should be useful for laboratory staff for selecting which blood smears to check optically.
authors.affiliation: Services d'Hématologie Biologique, University Hospital at Nancy, Vandoeuvre, France.
authors.forename: J-F
authors.initials: JF
authors.lastname: Lesesve
authors.affiliation: d'Epidémiologie et Evaluation Cliniques (Pôle S2R), University Hospital at Nancy, Vandoeuvre, France.
authors.forename: E
authors.initials: E
authors.lastname: Speyer
authors.affiliation: Sysmex Europe GmbH, Norderstedt, Germany.
authors.forename: J-P
authors.initials: JP
authors.lastname: Perol
mesh_terms: D057205:Automation, Laboratory; D001772:Blood Cell Count / Q000295:instrumentation* / Q000379:methods / Q000592:standards*; D004906:Erythrocyte Count / Q000295:instrumentation / Q000379:methods / Q000592:standards; D004912:Erythrocytes / Q000473:pathology*; D004913:Erythrocytes, Abnormal / Q000473:pathology; D006801:Humans; D012016:Reference Values; D012156:Reticulocytes
keywords: Fragmented red cell; Sysmex XN; automated blood cell counter; reference range; schistocytes