The article describes the experience with haematological analyzers in the high-end category – high output, five-population differential count, reticulocyte analysis. The analyzers Abbott CD 4000, Advia 120, Coulter Counter Gen’s and Sysmex SE 9500 were tested. The testing was concentrated on problem areas – white cell counts, discrimination between leukocytes and normoblasts, false positive and negative differential counts. All analyzers gave constantly good results, surprisingly the most problematic area was the evaluation of the leukocyte counts.

        Key words: haematological analyzers, differential count, reticulocytes