Concept of a point of care test to detect new oral anticoagulants in urine samples

  • PDF / 177,469 Bytes
  • 5 Pages / 595.28 x 793.7 pts Page_size
  • 53 Downloads / 213 Views

DOWNLOAD

REPORT


REVIEW

Open Access

Concept of a point of care test to detect new oral anticoagulants in urine samples Job Harenberg1*, Sandra Krämer1, Shanshan Du1, Christel Weiss2 and Roland Krämer3

Abstract New oral anticoagulants (NOAC) are approved for several indications for prophylaxis and treatment of venous thromboembolism and for prevention of embolism in atrial fibrillation at fixed daily doses without need of laboratory guided dose adjustment. Due to their low molecular weight of about 500 to 600 Dalton and their hydrophilicity free anticoagulant is excreted immediately through glomerular filtration into the urine. Impairment of renal function may increase the plasma concentration of the anticoagulants and lowered creatinine clearance is a declared contraindication. In contrast to the initial aim of development the anticoagulant effect is required to be determined in special clinical situations. Several specific and non-specific assays using plasma samples are currently undergoing standardization. As all NOACs are excreted into the urine, specific assays were developed for this matrix to determine them quantitatively of qualitatively. Urine samples can be easily and repetitively obtained avoiding problems and risks associated with blood sampling. The qualitative assay can be performed as a point of care test (POC) also by the patient by judging the different colours for the absence or presence of the drugs with the naked eye. The test is rapid (results available within 15 min), sensitive, specific and accurate and does not require a purified NOAC as control. The tests may be a tool for clinicians who need to know for treatment decisions if a NOAC is on board or not. As the tests are specific for oral direct thrombin inhibitors and for oral direct factor Xa inhibitors, the indication does not interfere with other qualitative POC test in development using clotting systems. The test may be indicated for patients at acute hospitalization, before surgery or central nervous system puncture anaesthesia, if fibrinolytic therapy is indicated, acute deterioration of renal function, and for control of adherence to therapy. Keywords: Oral anticoagulant, Dabigatran, Rivaroxaban, Apixaban, Renal function, Anticoagulation, Urine, Coagulation assay, Monitoring, Compliance

Introduction Thromboembolic complications are one of the major complications following primary elective total hip (THR) and knee replacement (TKR) surgery with considerable morbidity and mortality, which can be reduced substantially by subcutaneous low-molecular weight heparins and new oral anticoagulants [1]. Cerebral and noncerebral embolism is the most relevant severe event occurring in patients non-valvular atrial fibrillation (AF) which can be effectively prevented by vitamin-K antagonists (VKA) [2]. Limitations of the conventional regimes for prophylaxis of venous thromboembolism (VTE) with * Correspondence: [email protected] 1 Clinical Pharmacology, Medical Faculty of Medicine Mannheim, Ruprecht-Karls-University Heidelberg, Heidelberg,