Clinical Usefulness of the Simple Technique To Diagnose Thrombocytopenia Using Immature Platelet Fraction (IPF).

Background : It is defined that immature platelet fraction (IPF) is the percentage of reticulated platelet (RP) of total platelet count. We have measured an IPF reference range using XE-2100 blood cell counter with upgraded software (Sysmex, Kobe, Japan) and evaluated the clinical utility of this parameter for the laboratory diagnosis of thrombocytopenia due to increased peripheral platelet destruction.

Materials and methods : Peripheral blood samples collected into K2EDTA (Beckton Dickinson, Franklin Lakes, NJ, USA) were analysed at Chonbuk National University Hospital. 142 samples from apparently healthy adults (all routine full blood count parameters including platelets within the healthy reference range) were used to establish a normal reference range for the IPF%. The patients are classified 3 group including hypoplastic (consisted of 22 patients undergoing chemotherapy with falling platelet counts and 14 with aplastic anemia), destructive (14 with ITP and 7 with infection), and cirrhotic (40 with cirrhosis of liver).

Results : An IPF reference range in healthy individuals was established as 0.4~5.4%, with a mean of 1.7%. The significant increase in IPF values was found in destructive patient group. The cut-off value of IPF is 6.0%, its sensitivity and specificity are 95.2%, 82.9% respectively. Reproducibility was good.

Conclusion : A rapid, inexpensive automated method for measuring the IPF% is feasible and should become a standard parameter in evaluating the thrombocytopenic patient.