EVALUATION OF LABORATORY TESTS FOR LUPUS ANTICOAGULANT IN A GROUP OF CHINESE LUPUS PATIENTS

The sera of 69 Chinese patients with systemic lupus erythematosus were tested for the presence of lupus anticoagulant (LA) by a panel of lab oratory tests: Kaolin clotting time (KCT), dilute Russell viper venom time (DRVVT) and platelet neutralization procedure (PNP). The prevalen ce of LA varied among the 3 tests (10-19%), and was 10% when LA was co nsidered present if either KCT or DRVVT and the PNP were positive. Con cordance was fair between KCT and PNP, but was poor for DRVVT with eit her of the other 2 tests. Only 2 of our lupus patients had a history o f thrombo-embolic disease, and neither were serologically positive for LA. The incidence of thrombo-embolic diseases and that of LA were bot h too low in this group of Chinese lupus patients for their associatio n to be evaluated.