Von Willebrand factor and fibrinolytic parameters during the desmopressin test in patients with Cushing's disease

AIMS Desmopressin, a vasopressin analogue, is used for various clinical purposes, including haemostasis and, in recent times, the diagnostic work-up of patients with Cushing's syndrome, a condition associated with a known prothrombotic profile. We decided to evaluate whether and to what extent a diagnostic dose of desmopressin induces significant changes in endothelial parameters in patients with Cushing's disease (CD) and obese and normal weight controls.METHODS Twelve patients with CD, 10 obese and five normal weight controls were studied. Von Willebrand antigen (VWF : Ag), tissue plasminogen activator (t-PA) and plasminogen activator inhibitor type 1 (PAI-1) were measured at baseline and up to 4 h after 10 μg desmopressin i.v.RESULTS Desmopressin 10 μg transiently increased VWF : Ag and t-PA and decreased PAI-1 in all subjects. The magnitude of the VWF : Ag and t-PA increases after desmopressin was comparable in the three groups (VWF : Ag peak-to-basal ratio 1.9 ± 0.17, 1.5 ± 0.11 and 1.8 ± 0.13 and t-PA peak-to-basal ratio 1.6 ± 0.18, 1.6 ± 0.20 and 1.8 ± 0.24 for CD, obese and controls, respectively, all NS). The PAI-1 decrease observed in patients with CD was comparable with obese (0.7 ± 0.07 and 0.6 ± 0.09, NS) and controls (0.7 ± 0.07 vs. 0.4 ± 0.09, P= 0.08).CONCLUSIONS Administration of desmopressin to patients with CD for diagnostic purposes induces a transitory increase in VWF : Ag counterbalanced by a decrease in PAI-1 and increase in t-PA. The magnitude of these changes is largely comparable with that observed in obese and normal weight controls. Our data show that testing with desmopressin does not induce disease-specific changes in endothelial markers in patients with CD.