Heparin-induced thrombocytopenia-II in hospitalized patients with surgery or deep vein thrombosis.

Objectives: Heparin-induced thrombocytopenia (HIT) is clinically the most relevant non-hemorrhagic complication of heparin, which is associated with the increased risk of thrombosis and mortality. This study was conducted to determine platelet activation in HIT-II in hospitalized patients with surgery or deep vein thrombosis (DVT). The clinical outcomes of the patients was also assayed.

Methods: In this descriptive/cross-sectional study, 754 heparin-receiving-hospitalized patients with surgery or DVT were evaluated for the incidence of thrombocytopenia 7 days after heparin therapy. Clinical assessment 4Ts and ELISA for heparin-platelet factor 4 (HPF4) antibodies were performed to diagnose HIT-II. Production of platelet microparticles (PMPs), soluble P-selectin (sP-selectin), IL-1, IL-6, and tumor necrosing factor-α (TNF-α) were evaluated in the HIT suspected patients.

Results: The frequency of HIT-II was 4.50%. More HIT-II was diagnosed in the elder patients (P = 0.008) and female (P = 0.005). Thrombosis rate was higher in the HIT-II (P = 0.0001). More PMPs, sP-selectin, IL-1, IL-6, and TNF-α was detected in the HIT-II patients. The length of hospital stay was significantly different in HIT-II (P = 0.015). Mortality rate of the HIT-II patients was higher than non-HIT ones (P = 0.0007).

Conclusion: Platelet activation in the HIT-II patients mediated more thrombosis formation. It was associated with the increased length of hospital stay and mortality.