Objectives: Management of preanalytical, analytical and post-analytic processes is essential to obtain reliable results
in clinical biochemistry laboratories. One of the most significant of these processes is ensuring sample stability. In this
study, we aimed to evaluate hourly changes of leukocyte parameters at room temperature for 24 hours.
Methods: In this study, 30 randomly selected hemogram samples from Kocaeli University Faculty of Medicine Central Laboratory were included. These samples were analyzed on the Beckman Coulter Unicel DXH 800 analyzer (Beckman Coulter, Miami, FL) immediately after being admitted to the laboratory (0. hour) and after waiting for 2, 4, 8, 24
hours in the room (23-25°C), the results were repeated again. In this study, leukocyte, lymphocyte, basophil, neutrophil,
monocyte, eosinophil parameters were evaluated using the GraphPad Prism 6 program. The values were expressed as
mean±Standard deviation (SD). P<0.05 was used for statistical significance.
Results: A statistically significant difference was observed in the levels of leukocyte, lymphocyte, basophil, neutrophil
and monocyte parameters. No significant difference was observed in eosinophil levels. The findings showed that the
earliest increase occurred in neutrophil and lymphocyte values at the 2nd hour (p<0.001). An increase in the 4th-hour
measurements was observed in basophil and monocyte levels (p<0.001).
Conclusion: Our study showed that leukocyte subparameters, neutrophils and lymphocytes were the earliest affected
parameters. Our findings suggest that when the waiting times of hemogram samples exceed two hours, the results will
not be reliable concerning leukocyte parameters.
Keywords: Leukocyte, hemogram, preanalytical stage