Evaluation of the LaserCyte: an in-house hematology analyzer for dogs and cats

Abstract

In the present study, the LaserCyte instrument, a fully automated flow cytometer for use in veterinary practice, was evaluated for dogs and cats. Precision (coefficient of variation, CV) for red blood cell (RBC) parameters was 3.9%, for reticulocytes between 14.9 and 102%, for white blood cells (WBC) between 3 and 9.5%, for neutrophils between 3.9 and 6.5%, for lymphocytes between 7 and 17.9%, for monocytes between 4.9 and 13.1%, for eosinophils between 10.4 and 32.1%, for basophils between 7.8 and 32%, for platelets between 3.1 and 13.2%, and for platelet indices between 0 and 28.2%. The range of linearity extended the reference ranges. The agreement with reference methods (coefficient of correlation, r) were 0.96 (RBC), 0.94 (hematocrit), 0.96 (hemoglobin), 0.95 (mean corpuscular volume), 0.94 (WBC), 0.93 (neutrophils), 0.77 (lymphocytes), 0.77 (monocytes), 0.29 (eosinophils), 0.03 (basophils), 0.13 (reticulocytes), and 0.86 (platelets). The LaserCyte allowed the correct assessment of RBC and WBC parameters with respect to clinical relevance in the majority of samples. Lymphocytopenia was detected in only 51 out of 89 cases and monocytopenia in one out of 11 cases. The reticulocyte counts were correctly estimated in 85 out of 149 cases. It was concluded that the LaserCyte allowed reliable determination of the RBC parameters, WBCs, neutrophils in both species and platelets in dogs. Based on its capability to reliably determine feline platelets and of the parameters mentioned above, this instrument is considered a useful in-house analyzer for the veterinary practice. Qualitative microscopic assessment of blood smears is still necessary for detecting abnormal cell morphologies, certain cell precursors and blood parasites.

Spurious reticulocyte profiles in a dog with babesiosis

“…The Sysmex and the ProCyte perform an optical reticulocyte count using the same fluorescent dye polymethine, whereas the LaserCyte uses the classical NMB to stain ribonucleic acid (RNA) in cells. Reticulocytes with increased RNA content are displayed on the right of the reticulocyte scattergram as the “tail of the comet” and the resulting reticulocyte count has been shown to be more or less correlated with the manual count depending on the analyzer and the concentration of reticulocytes …”

“…Reticulocytes with increased RNA content are displayed on the right of the reticulocyte scattergram as the "tail of the comet" and the resulting reticulocyte count has been shown to be more or less correlated with the manual count depending on the analyzer and the concentration of reticulocytes. [3][4][5][6] In our case, parasite RNA was most probably falsely interpreted as reticulocyte RNA, explaining the incorrect reticulocyte count using the Sysmex and the Procyte. 1,7 Careful gating of reticulocytes is crucial to determine accurate counts, because polymethine also stains RNA in platelets and WBC.…”

Errors in basophil enumeration with 3 veterinary hematology systems and observations on occurrence of basophils in dogs

“…Canine and feline basophils are not detected by most automated instruments, including the Sysmex XT‐2000iV, CELL‐DYN 3500, Technicon H‐1 (precursor to the Advia 120 and 2120), and likely the Lasercyte, and are often underestimated by manual methods, contributing to the view that basophilia is rare in dogs. On blood smears, canine basophils may be classified inaccurately as monocytes or toxic neutrophils because basophils may have few granules or unstained or poorly stained granules (Figure ), especially when stained with aqueous stains …”

Comparative clinical study of canine and feline total blood cell count results with seven in‐clinic and two commercial laboratory hematology analyzers

“…[2][3][4][5][6][7] Only a few studies have been carried out to compare other in-clinic hematology analyzers to reference laboratory methods. [8][9][10][11][12][13][14][15][16] In addition, no comparisons on the flags and their accuracy and clinical importance have been published in veterinary medicine.…”