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Objectives: This study established the performance characteristics of DOAC-Remove for neutralization of the effects of rivaroxaban and apixaban in lupus anticoagulant (LAC) testing.Methods: Normal donor, LAC control, and patient samples were spiked with rivaroxaban or apixaban to simulate their effects on the dilute Russell's viper venom time (dRVVT), activated partial thromboplastin time (APTT), and dilute prothrombin time (dPT). Anti-Xa activity was measured after spiking and after DOAC-Remove neutralization. Accuracy, complex precision, and reference interval verification were evaluated.Results: DOAC-Remove neutralized rivaroxaban and apixaban concentrations as high as 415 ng/mL and 333 ng/mL, respectively. Percentage positive and negative agreement between the baseline and postneutralization interpretations were 75% or higher for the dRVVT and APTT methods but not for the dPT method. Coefficients of variation (CVs) were 10% or less for all assays except the Staclot-LA delta, which had a standard deviation of 2.5 seconds or CV of 25% or less depending on the level. The laboratory's reference intervals were verified for the dRVVT and APTT assays after DOAC-Remove treatment but not for the dPT assays.Conclusions: DOAC-Remove appears to have acceptable performance characteristics for neutralizing the effects of rivaroxaban and apixaban in the dRVVT and APTT methods but not in the dPT method. [ABSTRACT FROM AUTHOR]

Lee Y-S, Miller M, Hassett AC, Lee-Kim B-Y, Kim JJ, Haracznak M, Ranade S, Wood J, Reddy R, Kupfer DJ, Bontempo F, Nimgaonkar VL. von Willebrand's disease and psychotic disorders: co-segregation and genetic associations. Bipolar Disord 2004: 6: 150–155. © Blackwell Munksgaard, 2004 To evaluate co-segregation and genetic associations between von Willebrand's disease (vWD) and psychotic disorders. The study was initiated following ascertainment of a nuclear family in which four members were diagnosed with vWD and psychotic/mood disorders. As co-segregation was uncertain in the extended pedigree, we also investigated population-based linkage and association using polymorphisms of vWF, the gene conferring susceptibility to vWD. Three common vWF polymorphisms were investigated among 194 patients with psychotic disorders (bipolar I disorder, BD I; schizoaffective disorder, SZA and schizophrenia, SZ) and their parents. The cases were also compared with unrelated population-based controls (n = 183). The transmission disequilibrium test and related analyses suggested nominally significant transmission distortion of one allele and related haplotypes to the probands from their parents. The most significant results were obtained among patients with BD I, and similar trends were also evident in the SZ sample. Comparisons between the cases and population-based controls did not reveal associations, though marginally significant case–control differences were obtained in the BD I sample. These studies are consistent with association and linkage between vWF and BD I. However, given the relatively small sample, stochastic variation is an alternative explanation. [ABSTRACT FROM AUTHOR]