ODREĐIVANJE INDEKSA ALKALNE FOSFATAZE LEUKOCITA PRIMENOM CITOHEMIJSKOG BOJENJA

Abstract

Introduction. Leukocyte alkaline phosphatase is an enzyme found in white blood cells, with its activity measured by the
leukocyte alkaline phosphatase score. The aim of this study was to determine the optimal performing time and the primary biological sample in order to optimize the above laboratory analysis.

Material and Methods. A prospective study was conducted from December 2023 to July 2024 at the Center of Laboratory Medicine, University Clinical Center of Vojvodina,
involving 80 patients. Among them, 50 had confirmed leukocytosis with absolute neutrophilia, while 30 had normal white
blood cell count. Leukocyte alkaline phosphatase was measured from capillary and venous blood samples immediately
after collection, three hours post-collection, and seven days post-collection. All samples were prepared using the modified
Kaplow method. The leukocyte alkaline phosphatase score is graded from 0 to 4 based on the ability of granulocytes to absorb certain amount of reagent according to the degree of enzyme activity.

Results. The analysis revealed statistically
higher leukocyte alkaline phosphatase scores in capillary blood samples compared to venous blood (62 (2-305) vs. 52 (5-292) vs. 50 (6-275) vs. 42 (2-280), p= 0.000). A significant decline of the score was observed in venous blood samples if the analysis is performed immediately after venipuncture, at 3 hours (52 (5-292) vs. 50 (6-275), p=0.021), and at 7 days post-sampling (52 (5-292) vs. 42 (2-280), p=0.000).

Conclusion. Both the type of blood sample and the kinetics of the determination time affect the reliability of leukocyte alkaline phosphatase score results.