Size distribution of leukocyte aggregates differentiate between stress‐ and infection/inflammation‐related leukocytosis

We evaluated the state of leukocyte adhesiveness/aggregation in the peripheral blood of 33 patients with stress and 33 patients with infection/inflammation. Both groups had a similar white blood cell count (9542±3067 and 10,512±2758 cells per cmm, respectively). It was found that the percentage of aggregated leukocytes in the peripheral blood of patients with infection/inflammation was significantly higher than in the patients with stress (24.7±11 per cent versus 15.8±6 per cent; p<0.0001). When we analyzed the size distribution of the aggregated cells we also found a significant difference between the number of couplets (2.7±1.9 versus 1.6±0.9; p=0.006), triplets (0.6±1.3 versus 0.2±0.2; p=0.05), quadruplets (0.14±0.2 versus 0.03±0.07; p=0.005) or quintets (0.04±0.1 versus 0.003±0.002; p=0.05) between these two groups. Thus, by using a simple slide test to reveal the state of leukocyte adhesiveness/aggregation in the peripheral blood one could favor the diagnosis of infection/inflammation induced leukocytosis as opposed to a stress-related one. Copyright © 2000 John Wiley & Sons, Ltd.