Feasibility of DOAC Dipstick point-of-care testing in patients with acute stroke and transient ischemic attack

Background In patients with acute stroke, the plasma concentrations of direct oral anticoagulants (DOACs) need to be known for further treatment decisions. The point-of-care test DOAC Dipstick contains two test pads that determine levels of direct factor Xa (FXA) inhibitors and thrombin (THR) inhibitors in urine samples; thereby determining DOAC plasma levels of > 30 ng/mL within 10 minutes. Aim This study aimed to test the feasibility of using the DOAC Dipstick to detect the presence of DOACs in patients with acute stroke and transient ischemic attack (TIA) during the early phase of intrahospital stroke management. Methods Urine samples from patients with acute stroke and TIA with or without DOAC intake were obtained within 8 hours after hospitalisation. The urine samples were tested using the DOAC Dipstick. After incubation, colour change on the DOAC Dipstick pads were analysed visually and using a semi-automated reader. Primary endpoints were the success rate of evaluable pad results and time to results after urine sampling. Results From January 2023 to April 2024, 70 patients were recruited, 66 of whom fulfilled the inclusion criteria (39% female, mean age 73 ± 11.9 years). The median (interquartile range) times from urine sample collection to visual and reader test pad results were 20 (15-26) mins and 24 (16-37) mins, respectively. The test procedure was uncomplicated in most patients (n = 60). Complications in the test procedure were delays in urine sampling (n = 3), need for repeated testing due to dry strip (n = 2), no visual evaluability of the test result (n = 1), and abnormal urine colour (n = 1). The urine samples of all patients with prior DOAC intake (n = 26) were positive for DOACs while those for all patients without prior DOAC intake (n = 39) were negative for DOACs (one patient was excluded because the urine sample was not collected in time). Conclusion The DOAC Dipstick rapidly and reliably detects DOACs in urine samples from patients with acute stroke and TIA.