Differential blast counts obtained by automated blood cell analyzers.

Background: Automated blood cell analyzers often read leukemic blasts as normal cells. In this study, we evaluated the 5-part differential patterns of blasts using automated analyzers to determine if they can differentiate among blast types.

Methods: Blood samples containing 10% or more blasts were collected from patients with acute leukemia (N=175). The 5-part differential count was conducted using DxH 800 (Beckman Coulter, USA) and XE-2100 analyzers (Sysmex Co., Japan), and the results were compared with manual differential counts, which was used as a reference method.

Results: The DxH 800 reported the 5-part white blood cell differential count in 98.9% of the cases. The XE-2100 provided an invalid automated differential count in 72% of the cases. Both analyzers counted most lymphoblasts as lymphocytes and most myeloblasts as monocytes. In 11 cases, the DxH 800 reported a 5-part differential count without a blast flag.

Conclusions: Some automated analyzers are able to recognize and count blasts according to their characteristic cell types. Therefore, complete blood counts obtained automatically can provide valuable data for making provisional decisions regarding the lineage of leukemia cells before further investigation.