Evaluation of an automatic hematology analyzer in patients with nonhematologic conditions

The Coulter STKS is a new automated hematology analyzer that provides complete blood counts (CBCs) and a five-part white blood cell (WBC) differential count. This study evaluated its performance and determined its value in reducing the extensive manual work required to obtain WBC differential counts from patients with nonhematologic conditions. The evaluations included precision, carryover, effects of storage duration and temperature, comparison of primary (automated) and secondary (manual) methods of aspiration, comparison with the Technicon H*1 machine, and WBC differential capability. Both primary and secondary methods provided CBC values that were precise, repeatable, and satisfactory. The WBC differential results also were accurate and comparable to those obtained manually. The Coulter STKS not only precisely analyzes CBCs but also screens blood samples without WBC abnormalities, as it has a 98% predictive value of negative test results. This instrument is suitable for use in nonhematology patients in large medical centers, teaching hospitals, and general hospitals.