Aim: Heparin-induced thrombocytopenia (HIT) is a rare, life-threatening, immune-mediated adverse effect of heparin administration. This study compares frequently used laboratory assays in terms of their effectiveness in HIT diagnosis.Materials & methods: Fifty patients with suspected HIT were tested by gel immunoassay and solid phase PF4/heparin antibody ELISA. On positive results, platelet activation markers P-selectin and Annexin V were assayed using flow cytometry.Results: Thirty/50 patients were negative for both immunoassays. Flow cytometry was performed in the 20 immunoassay positive patients. Platelet activation was observed in 7/20 in the presence of low heparin concentration (0.2 IU/ml).Conclusion: The results are in accordance with the currently available literature and flow cytometry seems a promising alternative in HIT laboratory investigation.
Keywords: Annexin V; ELISA; P-selectin; PaGIA; anti-PF4/heparin antibodies; flow cytometry; heparin-induced thrombocytopenia; platelet activation.
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