J Clin Pathol 65:1024-1030 doi:10.1136/jclinpath-2012-200930
  • Original articles

Performance evaluation of the Sysmex haematology XN modular system

  1. Samuel J Machin1
  1. 1Department of Haematology, University College London Hospital, London, UK
  2. 2Department of Haematology, The Doctors Laboratory, London, UK
  1. Correspondence to Carol Briggs, Department of Haematology, University College London Hospital, Haematology Evaluations, 5th Floor, 60 Whitfield Street, London W1T 4EU, UK; carolbriggs{at}
  • Accepted 18 June 2012
  • Published Online First 31 July 2012


Background The Sysmex XN haematology instrument performs automatic reflex testing, depending on sample results. A nucleated red blood cell (NRBC) count is provided on all samples. The instrument has a smaller footprint (34%) than previous Sysmex XE analysers.

Methods An evaluation comparing all results to the Sysmex XE-2100 and manual microscopic differential and morphology (n=390) was performed followed by a workflow study of 1000 samples to compare speed of operation and number of blood films reviews required from both systems.

Results The new features on the instrument are: (1) white cell and NRBC channel, all samples include the NRBC count; (2) white cell precursor channel: false positive flags for blasts, abnormal lymphocytes and atypical lymphocytes are reduced significantly without a statistical increase of false negatives; (3) low white cell count mode: suggested setting of <0.5×109/l. An extended count is more precise and provides an accurate differential. Fluorescent platelet count is performed in a dedicated channel. If the red cell or platelet size histograms are abnormal or if the platelet count is low, then a fluorescent platelet count is automatically performed. Good correlation with the XE-2100 and manual differential was found and the improved results compared to the reference flow cytometric analysis for platelet counts, especially below 30×109/l (XE-2100, R2=0.500; XN, R2=0.875).

Conclusion The XN showed reduced sample turnaround time of 10% and reduced number of blood films for examination, 49% less than the XE-2100 without loss of sensitivity with more precise and accurate results on low cell counts.