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

We evaluated the state of leukocyte adhesiveness/aggregation in the periphe ral blood of 33 patients with stress and 33 patients with infection/inflamm ation. Both groups had a similar white blood cell count (9542 +/- 3067 and 10,512 +/- 2758 cells per cmm, respectively). It was found that the percent age of aggregated leukocytes in the peripheral blood of patients with infec tion/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 ana lyzed the size distribution of the aggregated cells we also found a signifi cant 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), quadr uplets (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 u sing a simple slide test to reveal the state of leukocyte adhesiveness/aggr egation in the peripheral blood one could favor the diagnosis of infection/ inflammation induced leukocytosis as opposed to a stress-related one. Copyr ight (C) 2000 John Wiley & Sons, Ltd.