Validation of blood counters for quality control of platelet concentrates with high platelet counts

Abstract

AbstractBackgroundBlood counters are primarily used to measure peripheral blood cells including platelets (PLTs). In routine quality control of platelet concentrates (PCs), counters are also used to analyze very high PLT counts. To meet the requirements of national and European guidelines for quality assurance, the accuracy of counting very high PLT counts has to be validated. The aim of the present study was to validate four blood counters (one of which has two detection methods) focusing on the PLT count.MethodsThe comparison was performed with PCs using the blood counter devices CELL-DYN Ruby (optical count) and CELL-DYN Emerald (impedance count), Sysmex K-4500 (impedance count), Sysmex XN-550 (impedance count) and Sysmex XN-550 (optical count). For precision performances, samples were measured serially 5 times and the coefficients of variation were calculated and compared with manufacturers’ requirements. Additionally, 50 peripheral blood samples were analyzed and standard hemogram parameters (red blood cells [RBC], white blood cells [WBC], hemoglobin [HGB], hematocrit [HCT], PLTs) were compared.ResultsThe comparison showed significant differences between the studied blood counter devices in measuring high PLT counts. The CELL-DYN-Emerald, the Sysmex K-4500 and Sysmex XN-500 with the optical counting method measured significantly higher PLT counts compared to the CELL-DYN-Ruby and the Sysmex XN-500 with the impedance counting technology (p<0.0001) independent of their principle of measurement. The manufacturers provide comparable coefficients of variation. We achieved similar results for all counters. All results of the peripheral blood count parameters were comparable.ConclusionsOur study showed the importance of blood counter validations focusing on PCs with high PLT counts before routine use. Not only the generally fundamental method, but also the manufacturers’ peculiarities seem to play an important role.