Repeated early hemofiltration filters clotting and heparin-induced thrombocytopenia in ICU.

[heparin-induced thrombocytopenia]

Repeated early hemofiltration filter clotting are real thrombotic events . Diagnosis of heparin-induced thrombocytopenia (HIT ) in this setting in ICU remains difficult . We describe two cases of repeated early hemofiltration filters clotting in ICU and to evaluate their impact on the probability test 4 T 's score and diagnosis of HIT . Two patients undergoing at least three repeated early hemofiltration clotting filters in <6 Â h revealing HIT in ICU had a low probability score for HIT . Despite a 4 T 's score of three for the two patients and persistent early hemofiltration clotting filters , functional tests for HIT antibodies (heparin induced platelet activation assay and serotonin release assay ) were positive , permitting the diagnosis of HIT in both patients . We suggest that the occurrence of repeated , rapid (within 6 Â h ) hemofiltration filter clotting should score as two points for "Thrombosis " in the 4 T 's scoring system , thereby increasing the pretest probability for HIT in this clinical situation .