The values of the 100 cells are added and the total score reported. Make six smears on frosted end slides from fingerstick blood.
Air dry the slides.
Storage Instructions Maintain specimen at room temperature. Methodology Enzyme reaction with leukocyte alkaline phosphatase liberating naphthol or a substituted naphthol compound which then couples with fast blue RR or other chromogen to form an insoluble precipitate. One hundred cells are counted and the score totalled. Additional Information Low scores have been associated with CML, PNH, thrombocytopenic purpura, and hereditary hypophosphatasia. In CML regardless of the total white count, the score remains low.