Validation of the Sysmex XT‐2000iV hematology system for dogs, cats, and horses. I. Erythrocytes, platelets, and total leukocyte counts

Abstract

The Sysmex XT-2000iV is a laser-based, flow cytometric hematology system that has been introduced for use in large and referral veterinary laboratories. The purpose of this study was to validate the Sysmex XT-2000iV for counting erythrocytes, reticulocytes, platelets, and total leukocytes in blood from ill dogs, cats, and horses. Blood samples from diseased animals (133 dogs, 65 cats, and 73 horses) were analyzed with the Sysmex XT-2000iV and the CELL-DYN 3500. Manual reticulocyte counts were done on an additional 98 canine and 14 feline samples and manual platelet counts were done on an additional 73 feline and 55 canine samples, and compared with automated Sysmex results. Hemoglobin concentration, RBC counts, and total WBC counts on the Sysmex were highly correlated with those from the CELL-DYN (r>/=0.98). Systematic differences occurred for MCV and HCT. MCHC was poorly correlated in all species (r=0.33-0.67). The Sysmex impedance platelet count in dogs was highly correlated with both the impedance count from the CELL-DYN (r=0.99) and the optical platelet count from the Sysmex (r=0.98). The Sysmex optical platelet count included large platelets, such that in samples from cats, the results agreed better with manual platelet counts than with impedance platelet counts on the Sysmex. Canine reticulocyte counts on the Sysmex correlated well (r=0.90) with manual reticulocyte counts. Feline reticulocyte counts on the Sysmex correlated well with aggregate (r=0.86) but not punctate (r=0.50) reticulocyte counts. The Sysmex XT-2000iV performed as well as the CELL-DYN on blood samples from dogs, cats, and horses with a variety of hematologic abnormalities. In addition, the Sysmex detected large platelets and provided accurate reticulocyte counts.