Automated leucocyte differential counts in chronic lymphocytic and hairy-cell leukaemias: a comparison of the Hemalog D, H6000 and Coulter S Plus IV.

The automated peripheral blood differential counts produced by the Hemalog D, H6000 and Coulter S Plus IV were analysed and compared in 30 cases of chronic lymphocytic leukaemia (CLL) and 12 cases of hairy-cell leukaemia. All three machines were reliable in identifying CLL and HCL as a 'lymphocytosis' and in estimating neutrophil numbers in the disease. The Hemalog D and H6000 produced accurate monocyte counts in the two diseases, but the Coulter S Plus IV was unreliable in this regard since large lymphoid cells were identified as monocytes. The Haemalog D and H6000 were comparable in consistently identifying modestly raised large unstained cells (LUCs) in CLL. The Hemalog D, but not the H6000, was able to distinguish HCL from CLL on the basis of markedly raised LUCs.