Laboratory Test Reference Guide

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Platelet F (Fluorescent Platelet) by Sysmex XN CBC analysers is to date the most superior platelet count available from a routine haematology analyser. 

Standard platelet count based on DC detection (Impedance Platelet Count or PLT I) is routinely performed on all CBC requests for a whole blood sample (EDTA). But this method has limitations that may result in inaccurate platelet estimation. 

Possible interferences from PLT I:

– RBC fragments: falsely increased

– Microcytic RBCs: falsely increased

– Large platelets: falsely decreased

– WBC fragments: falsely increased

Platelet F is a next-generation method by Sysmex designed for a more accurate, precise and reliable platelet enumeration through routine processing. The Platelet F channel of Sysmex XN employs flow cytometry with the use of a fluorescence marker that labels the RNA inside the platelets. It has a very good correlation with CD41/CD61 through immunologic flow cytometry which is the gold standard for cell enumeration. 

Here in Waikato Hospital, PLT F is reported when needed in place of other methods such as PLT I or PLT O. Manual platelet counting is no longer performed in Waikato Hospital. Any request for manual platelet count will be processed for PLT F as part of CBC.

Note that Platelet F is performed automatically as needed and forms part of a CBC request.

FOR PATH ASSOC GROUP LABORATORIES ONLY: a request for Platelet F (Fluorescence Platelet) ONLY is to be registered as PLTFPATH, use the doctor code for the "Requesting doctor" PATHHAEMISL (Haematology Pathlab Waikato). Also, enter Pathlab PLT F as clinical detail. 

Adult tube (3mL EDTA):  minimum 1 mL

Pediatric EDTA tube:  minimum 250 uL