Background/Aim. Direct oral anticoagulants (DOACs) administration has a
significant interference on coagulation assays. Our study was conducted in
order to evaluate the effect of DOACs and DOAC Remove? on coagulation assays
during thrombophilia testing. Methods. In the period of January 2019 to the
end of June 2020 30 DOAC treated patients tested for thrombophilia, due to
venous thromboembolism (VTE), 14 females and 16 males aged 23 to 63 years
(median age 47.6 years), were included in the study. Thrombophilia testing
was performed using DOAC Remove? tablets (activated charcoal). The results
before and after DOAC Remove? were compared. Results. Positive LA results
were observed in 20% apixaban, 100% dabigatran, and 70% rivaroxaban treated
patient, while in samples after DOAC Remove? the LA positivity was observed
only in one from the apixaban group. Before DOAC Remove?, the APC-R ratio
was measurable in 40% dabigatran, and 80% rivaroxaban treated patients,
while, after using DOAC Remove? the APC-R was measurable in all cases.
Comparing the results obtained from the samples before and after DOAC
Remove?, a difference was noted in relation to all dRVVT tests, except for
the dRVVT ratio in the apixaban group. Clot-based methods for detection of
the APC resistance are significantly affected by dabigatran, and less by
rivaroxaban. Conclusion. DOAC was practically inactivated after the addition
of the DOAC Remove?, which made it possible to perform analyses for the LA
and APC-R testing freely and obtain relevant results.
Thrombophilia testing in the era of direct oral anticoagulants
