Abstract:

Objective: To investigate the correlation between diluted Russell viper venom time(dRVVT) test and mixing test in detection of lupus anticoagulant (LA) and their methodological characteristics. Methods: The clinical data of 31 patients with coagulation dysfunction and positive LA were collected from Ruijin Hospital, Shanghai Jiao Tong University from September 2015 to September 2019. The correlation between the results of standardized ratio of dRVVT and mixing test (Rosner index) was analyzed, and the similarities and differences of the two methods were explored. Results: The scatter diagram revealed that the standardized ratio of dRVVT had a close correlation with the activated partial thromboplastin time（APTT）, R1 and R2. Pearson correlation analysis showed that there was a significant correlation between the standardized ratio of dRVVT and the results of mixing test(r: 0.54-0.62). Conclusions: Although there is a significant correlation between dRVVT based on common pathway and the mixing test based on both intrinsic pathway and common pathway, yet it is not a strict linear correlation. The two methods cannot be completely replaced by each other in the detection of lupus anticoagulant, and it is suggested that the combined use of the two methods can improve the detection rate of lupus anticoagulant and reduce the misdiagnosis and missed diagnosis.

Key words: Lupus anticoagulant, Diluted Russell viper venom time, Mixing test, Rosner index