EVALUATION OF RECENTLY DESCRIBED TESTS FOR DETECTION OF THE LUPUS ANTICOAGULANT

It is known that lupus anticoagulants (LA) are antibodies which interf ere with phospholipid-dependent coagulation tests, but due to the hete rogeneity of LA and the differences in sensitivity of reagents and tes ts, the diagnosis of LA remains difficult. Recently, Triplett et al. ( 26) have proposed a new test based on two venoms, Textarin (T) and Eca rin (E), that activate prothrombin but differ in their phospholipid re quirements. By testing this new assay we have evaluated 36 patient pla smas containing LA according to standard tests (activated partial thro mboplastin time, dilute Russell viper venom time and platelet neutrali zation procedure) and our results confirm a high sensitivity for LA of the T/E test. In addition, we observed a greater sensitivity of the t issue thromboplastin inhibition test using a recombinant thromboplasti n instead of a human placenta thromboplastin. Our study also showed th at the T/E test seems to be a useful assay in confirming the diagnosis of LA in patients with an unexplained prolonged APTT.