Detecting Anti-IIa and Anti-Xa Direct Oral Anticoagulant (DOAC) Agents in Urine using a DOAC Dipstick

Abstract

The assessment of the anticoagulant effect of direct oral anticoagulants (DOACs) can be important for rapid medical decision-making, especially in patients needing immediate management. An assay that screens for the absence or presence of a DOAC would help accelerate treatment in these situations. Chromogenic and coagulation methods have several limitations, including limited accuracy, long turnaround time, and their need of specialized laboratories. Oral factor Xa and thrombin inhibitors are also eliminated by the kidneys and can be detected in patient urine samples using a single, rapid, sensitive, and patient-specific qualitative assay. In these tests, the presence or absence of a DOAC in urine can be identified by visually observing specific colors after a few minutes. Several studies have demonstrated the robustness and repeatability of these assays. The specific colors of the test strip also detect creatinine in the urine, which shows whether DOAC excretion is reduced, thus suggesting renal impairment. Persons with amblyopia may use a specific reader. Current indications for using the test include emergency medical situations with severe bleeding and thrombotic events or before urgent major surgical interventions to accelerate medical decision-making.

An update on laboratory assessment for direct oral anticoagulants (DOACs)

“…DOAC Dipstick (DOASENSE GmbH Heidelberg, Germany): A urine dipstick method that can screen and segregate dabigatran from anti‐Xa DOACs . The dipstick also features a creatinine pad to assess renal function.…”

“…DOAC Dipstick (DOASENSE GmbH Heidelberg, Germany): A urine dipstick method that can screen and segregate dabigatran from anti-Xa DOACs. 31 The dipstick also features a creatinine pad to assess renal function. Limitations include unreadable pads due to urine color, the lack of correlation with plasma DOAC concentrations, and delay between drug ingestion and urine detection (1 hour longer to detect in urine than in blood).…”

Accuracy of a Rapid Diagnostic Test for the Presence of Direct Oral Factor Xa or Thrombin Inhibitors in Urine—A Multicenter Trial

“…Therefore, the thrombin pad serves as a negative control for the factor Xa inhibitor test and vice versa. 7 We did not include a group of subjects not taking any DOAC.…”

“…[3][4][5] Various tests are in different stages of development. [6][7][8] Emergency situations with a need for point-of-care testing for the presence or absence of DOACs include emergent or urgent major surgical interventions, clinically relevant bleeding, or thrombotic episodes with known or unknown anticoagulant therapy, as well as the evaluation of unconscious patients or those unable to inform clinicians about their anticoagulant therapy. 9,10 Knowledge of the presence of a DOAC may inform use of expensive reversal agents, which would not be indicated in a patient without detectable DOAC exposure.…”

Progress in the monitoring of direct oral anticoagulant therapy

“…However, they may provide a rapid qualitative assessment of recent DOAC exposure (Gosselin et al, 2018). A DOAC dipstick (DOASENSE GmbH, Heidelberg, Germany) has been shown to accurately detect the presence of DOACS by visually observing specific colours after a few minutes (Harenberg et al, 2018).…”