HIGH-INCIDENCE OF ANTI-HEPARIN PLATELET FACTOR-4 ANTIBODIES AFTER CARDIOPULMONARY BYPASS-SURGERY/

Fifty-one patients undergoing cardiopulmonary bypass (CPB) were studie d on day 0 and day 8 for heparin-induced thrombocytopenia (HIT). The p latelet aggregation test (PAT) and tests for anti-heparin-platelet fac tor 4 (anti-H.PF4), anti-IL8 and anti-neutrophil activating peptide 2 (anti-NAPa) antibodies (Ab) were performed by ELISA. On day 8, 27% of patients were positive for anti-H.PF4Ab. None of these results were fo und to influence thrombotic complications or platelet counts after CPB . Our results suggest that IgG to H.PF4 may be considered a risk facto r, but that additional factors must be required for HIT to develop. We conclude that assays based on platelet activation would be more appro priate for the diagnosis of HIT after CPB.