#Platelets are cell fragments. manual#

Working on the impedance principle, the analyzer needs to be well calibrated to avoid erroneous measurement of the counts, as shown in this case. The computer in a well calibrated analyzer will then count each impedance event as either red blood cell, leukocyte or platelet depending on the size of the particle. The impedance to the flow of charges between two electrodes is equivalent to the size of the particle, as shown in ( Figure 3). According to Coulter impedance principle, in a closed electrical circuit through a conducting fluid medium, an impedance is created when small particles such as blood cells pass through an aperture between the two electrodes. The first and oldest principle is the “Coulter’s impedance principle”. Finally, the FBC was repeated using the Sysmex XN3000 via optical mode with reticulocyte-platelet channel that showed a normal platelet count of 153 × 10 9/L, as shown in Figure 1.Ī conventional haematology analyzer uses two main principles for the estimation of an absolute blood cell count.

#Platelets are cell fragments. manual#

A full blood picture was requested and showed aniso-poikilocytosis with numerous red blood cell fragmentation, with manual platelet count of 60-80 platelets per high power field (approximately equivalent to 300-400 × 10 9/L), as shown in ( Figure 2). All the high values were obtained using the Impedance mode by a newly installed Sysmex XN3000, shown in Figure 1. Two subsequent FBCs also showed platelet counts more than 2000 × 10 9/L.

She was subsequently followed up at the haematology clinic 6 months apart. On examination the patient had no hepatosplenomegaly. The patient had no signs or symptoms related to hyper-viscosity, or any bleeding tendencies. Two months earlier the platelet count was 339 × 10 9/L, also shown in ( Figure 1).

Furthermore, machines using the impedance principle need to be calibrated to reduce the chances of getting abnormal results with actual normal platelet counts.Ī 59-year-old lady with non-transfusion dependent Hb-H disease on regular follow up, was noted to have a very high platelet count, highest recorded value being 2158 × 10 9/L, during her clinic visits, as shown in Figure 1. Whenever an unexpected high platelet count is encountered, alternative modalities should be used to confirm the actual platelet count such as manual count on a blood film. Conclusion: A wide spectrum of blood disorders can cause pseudothrombocytosis. Manual platelet counts and the automated analysis using flowcytometric counting of the same analyser showed a normal platelet count. Case Report: We report a case of Haemoglobin-H disease that was noted to have a very high platelet count, by newly installed automated blood analyser, during regular follow up. Therefore, any abnormal platelet counts in a full blood count analysis should be re-evaluated either using blood film manual counting or with more accurate automated analysis options. Introduction: Red cell fragmentation may result in erroneously high platelet counts by automated blood counters.