Clinical significance of IPF% or RP% measurement in distinguishing primary immune thrombocytopenia from aplastic thrombocytopenic disorders

Int J Hematol. 2015 Apr;101(4):369-75. doi: 10.1007/s12185-015-1741-0. Epub 2015 Jan 25.


The diagnosis of primary immune thrombocytopenia (ITP) is based on differential diagnosis. Although the measurement of percentages of reticulated platelets (RP%) by flow cytometry is useful as a supportive diagnostic test, this method is nonetheless a time-consuming, laboratory-based assay. To identify alternative assays that are useful in daily practice, we compared three methods in parallel, IPF% measured by XE-2100 [IPF% (XE), Sysmex Corp.], IPF% measured by new XN-1000 [IPF% (XN)], and RP%. We examined 47 patients with primary ITP, 28 patients with aplastic thrombocytopenia (18 aplastic anemia and 10 chemotherapy-induced thrombocytopenia) and 80 healthy controls. In a selected experiment, we examined 16 patients with paroxysmal nocturnal hemoglobinuria (PNH) to examine the effect of hemolysis. As compared with IPF% (XE), IPF% (XN) showed better within-run reproducibility. The sensitivity and specificity for the diagnosis of ITP were 83.0 and 75.0 % for IPF% (XE), 85.1 and 89.3 % for IPF% (XN), and 93.6 and 89.3 % for RP%, respectively. Examination of PNH patients revealed that hemolysis and/or red blood cell fragments interfered with IPF% (XE) values, but not with IFP % (XN) values. Our results suggest that IPF% measured by XN-1000 may be of comparable value with RP% as a supportive diagnostic test for ITP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Blood Platelets / pathology*
  • Diagnosis, Differential
  • Female
  • Hemoglobinuria, Paroxysmal / blood
  • Hemoglobinuria, Paroxysmal / diagnosis
  • Hemoglobinuria, Paroxysmal / pathology
  • Hemolysis
  • Humans
  • Male
  • Middle Aged
  • Purpura, Thrombocytopenic, Idiopathic / blood
  • Purpura, Thrombocytopenic, Idiopathic / diagnosis*
  • Purpura, Thrombocytopenic, Idiopathic / pathology
  • Thrombocytopenia / blood
  • Thrombocytopenia / diagnosis
  • Thrombocytopenia / pathology
  • Thrombopoietin / blood


  • Thrombopoietin