OBJECTIVES: The beneficial effect of platelet transfusion on haemostasis is well established, but there is emerging evidence that platelet transfusion induces an inflammatory response in vascular endothelial cells.

BACKGROUND: We investigated haemostatic function and endothelial biomarkers before and after platelet transfusion in patients with acute myeloid leukaemia.

MATERIALS AND METHODS: Blood was sampled before, 1 and 24 h after platelet transfusion. Primary and secondary haemostasis was evaluated by whole blood aggregometry (Multiplate) and thromboelastography (TEG). Endothelial biomarkers (sICAM-1, syndecan-1, sThrombomodulin, sVE-Cadherin) and platelet activation biomarkers (sCD40L, TGF-beta) were investigated along with haematology/biochemistry analyses.

RESULTS: Twenty-two patients were included. Despite continued low platelet counts, platelet transfusion normalised the median values of most TEG parameters and slightly increased platelet aggregation (all P < 0·05). Endothelial biomarkers were not significantly affected by transfusion. The 1 h sCD40L level correlated positively with Syndecan-1 and soluble thrombomodulin delta values, biomarkers of endothelial damage (both P = 0·005).

CONCLUSION: Platelet transfusion improved haemostasis, whereas post-transfusion increases in sCD40L were associated with endothelial damage, indicating that transfused platelets and platelet-derived pro-inflammatory mediators may have opposite effects on the endothelium.