PT  - JOURNAL ARTICLE
AU  - Elvira Maličev
AU  - Marjeta Maček Kvanka
AU  - Polona Klemenc
AU  - Primož Rožman
TI  - The level of heparin-induced antibodies in correlation with the result of the flow cytometric functional assay in the patients with suspected HIT
AID  - 10.1136/jclinpath-2017-204498
DP  - 2017 Sep 13
TA  - Journal of Clinical Pathology
PG  - jclinpath-2017-204498
4099  - http://jcp.bmj.com/content/early/2017/09/13/jclinpath-2017-204498.short
4100  - http://jcp.bmj.com/content/early/2017/09/13/jclinpath-2017-204498.full
AB  - Heparin can induce the formation of antibodies against a heparin complex with a platelet factor 4 (PF4), leading to platelet activation and the development of heparin-induced thrombocytopaenia (HIT). Because screening ELISA does not discriminate between platelet activating and non-activating anti-heparin/PF4 antibodies, each positive result is confirmed by an additional functional assay. We analysed 1004 sera of patients with suspected HIT. Optical density (OD) values of ELISA-positive results were correlated with the risk for a positive result with our functional flow cytometric assay. Only 10.7% were ELISA positive and 59.8% of those were positive with the functional assay. The positive functional assay was found in 23.4% of patients with OD<1.0, in 57.7% with 1.0<OD<2.0 and in 94.1% with OD>2.0. Although our results showed that higher ELISA OD values increasethe possibility of the presence of platelet-activating anti-heparin/PF4 antibodies - , there is no need for improving ELISA cut-off value for positive result.