Background  Numerous studies have demonstrated increased cardiovascular risk in psoriasis. Circulating endothelial cells (CECs) have been proposed as a new marker of endothelial dysfunction that plays an important role in pathogenesis of atherosclerosis.

Objective  The aim of this study was to compare the number of CECs in psoriatic patients to a control group and to analyze possible correlations between the numbers of CECs and the plasma levels of classical markers of endothelial dysfunction, such as: sICAM-1, sE-selectin and von Willebrand factor (vWF).

Methods  The number of CECs, identified as CD146 + / CD45- cells, were determined in peripheral blood with using flow cytometry in psoriatic patients (n = 63) and controls (n = 31). The plasma levels of: sICAM-1, sE-selectin, vWF were measured with ELISA. The severity of psoriasis was assessed with PASI.

Results  The number of CECs was significantly increased in psoriatic patients compared with controls (< 0.00001) and positively correlated with disease severity (R = 0.360; = 0.0037). The levels of sICAM-1, sE-selectin and vWF were significantly elevated in psoriatic patients (P < 0.00001; P < 0.00001; P = 0.00072, respectively). The number of CECs was significantly, positively correlated with the levels of sICAM-1 (R = 0.393; P = 0.0014) and vWF (R = 0.314; P = 0.012) in psoriatic patients. The levels of sICAM-1 and sE-selectin were positively correlated with disease severity (R = 0.356; = 0.0041 and R = 0.407; = 0.0009, respectively).

Conclusion  The increased number of CECs that correlates with disease severity and plasma levels of sICAM-1 and vWF may indicate endothelial dysfunction or injury in patients with psoriasis.