Abstract: A method for detecting abnormality in the morphology of erythrocytes, which comprises:(1) mixing a sample containing erythrocytes with a sphere-forming reagent;(2) introducing the sample treated in the preceding step into a detector area of a flow cytometer;(3) measuring at least one scattered light at an angle reflecting the morphology of erythrocyte among the scattered lights emitted from the sample to obtain cell distribution data; and(4) comparing the cell distribution data with cell distribution data on normal erythrocytes that were determined beforehand.

Abstract: A hematological sample is treated with a hemolytic agent that maintains immature leukocytes in a viable state and damages other leukocytes. The damaged leukocytes are stained with a fluorochrome which can stain damaged cells. At least one kind of scattered light and at least one kind of fluorescence of the treated and stained blood cells are measured to classify and count leukocytes based on the intensities of the scattered light and the fluorescence. Highly precise measurement of immature leukocytes and simultaneous classification and counting of normal leukocytes are achieved.

Abstract: A reagent for measuring reticulocytes which has at least one dye which specifically stains reticulocytes and at least one dye which specifically stains leukocytes.