Reliability of Point-of-Care INR Measurements in Patients With Antiphospholipid-Antibody Syndrome Treated With Warfarin
Summary
The antiphospholipid-antibody syndrome (APLA), which includes lupus anticoagulant, anticardiolipin, and anti-beta-2-glycoproteinI antibodies, is a thrombophilic disorder associated with arterial thrombosis, venous thrombosis or both. Patients diagnosed with APLA have a higher risk of recurrent thrombosis than do patients without known antibodies. Currently, warfarin is considered the anticoagulant of choice for prophylactic antithrombotic treatment for APLA patients after their first episode of thrombosis. In some patients with APLA who are treated with warfarin, the INR values determined on plasma are unreliable due to an influence of the APLA on the INR. In these individuals, alternative monitoring methods, such as factor II activity, chromogenic factor X activity or prothrombin-proconvertin time should be used to assess adequate anticoagulation. These tests are expensive and not widely available to some clinicians. Point-of-care (POC) instruments, on the other hand, are readily accessible to clinicians. Previous research has shown that INR values from 3 older point-of-care (POC) instruments are unreliable in 1/3 of APLA patients (CoaguChekTM, ProTimeTM, INRatioTM). However, there are now newer versions of these POC instruments available (CoaguChek XSTM, an investigational ProTime device, and a newer INRatioTM device) and it is unknown if these newer POC instruments are reliable in patients with APLA. The purpose of this study is to determine whether newer POC instruments are reliable in patients with APLA.
Study Design
Observational Model: Case Control, Time Perspective: Prospective
Conditions
Antiphospholipid Syndrome
Intervention
INR by point-of-care instruments and venopuncture
Location
University of North Carolina at Chapel Hill
Chapel Hill
North Carolina
United States
27514
Status
Enrolling by invitation
Source
University of North Carolina, Chapel Hill
Results (where available)
Links
- Source: http://clinicaltrials.gov/show/NCT00878137
- Information obtained from ClinicalTrials.gov on July 15, 2010
Medical and Biotech [MESH] Definitions
Antibodies, Anticardiolipin
Antiphospholipid antibodies found in association with systemic lupus erythematosus (LUPUS ERYTHEMATOSUS, SYSTEMIC;), ANTIPHOSPHOLIPID SYNDROME; and in a variety of other diseases as well as in healthy individuals. The antibodies are detected by solid-phase IMMUNOASSAY employing the purified phospholipid antigen CARDIOLIPIN.
Sneddon Syndrome
A systemic non-inflammatory arteriopathy primarily of middle-aged females characterized by the association of livedo reticularis, multiple thrombotic CEREBRAL INFARCTION; CORONARY DISEASE, and HYPERTENSION. Elevation of antiphospholipid antibody titers (see also ANTIPHOSPHOLIPID SYNDROME), cardiac valvulopathy, ISCHEMIC ATTACK, TRANSIENT; SEIZURES; DEMENTIA; and chronic ischemia of the extremities may also occur. Pathologic examination of affected arteries reveals non-inflammatory adventitial fibrosis, thrombosis, and changes in the media. (From Jablonski, Dictionary of Syndromes & Eponymic Diseases, 2d ed; Adams et al., Principles of Neurology, 6th ed, p861; Arch Neurol 1997 Jan;54(1):53-60)
Antibodies, Antiphospholipid
Autoantibodies directed against phospholipids. These antibodies are characteristically found in patients with systemic lupus erythematosus (LUPUS ERYTHEMATOSUS, SYSTEMIC;), ANTIPHOSPHOLIPID SYNDROME; related autoimmune diseases, some non-autoimmune diseases, and also in healthy individuals.
Antiphospholipid Syndrome
The presence of antibodies directed against phospholipids (ANTIBODIES, ANTIPHOSPHOLIPID). The condition is associated with a variety of diseases, notably systemic lupus erythematosus and other connective tissue diseases, thrombopenia, and arterial or venous thromboses. In pregnancy it can cause abortion. Of the phospholipids, the cardiolipins show markedly elevated levels of anticardiolipin antibodies (ANTIBODIES, ANTICARDIOLIPIN). Present also are high levels of lupus anticoagulant (LUPUS COAGULATION INHIBITOR).
Lupus Coagulation Inhibitor
An antiphospholipid antibody found in association with systemic lupus erythematosus (LUPUS ERYTHEMATOSUS, SYSTEMIC;), ANTIPHOSPHOLIPID SYNDROME; and in a variety of other diseases as well as in healthy individuals. In vitro, the antibody interferes with the conversion of prothrombin to thrombin and prolongs the partial thromboplastin time. In vivo, it exerts a procoagulant effect resulting in thrombosis mainly in the larger veins and arteries. It further causes obstetrical complications, including fetal death and spontaneous abortion, as well as a variety of hematologic and neurologic complications.
Clinical Trials
The purpose of this study is to gather information about causes and treatment of Antiphospholipid Syndrome.
Antiphospholipid Syndrome Collaborative Registry (APSCORE)
Antiphospholipid Syndrome (APS) is an autoimmune disorder in which the body recognizes certain normal components of blood and/or cell membranes as foreign substances and produces antibodie...
This study is being done to see if there are any long term health related issues in women with APA and recurrent miscarriages.
Hematopoietic Stem Cell Transplantation in Patients With Antiphospholipid Syndrome
Antiphospholipid syndrome is disease believed to be due to immune cells, cells which normally protect the body, but are now producing the protein which leads to abnormal clotting in the b...
OBJECTIVES: I. Determine the induction of durable remission in patients with life-threatening systemic lupus erythematosus or antiphospholipid antibody syndrome treated with cyclophospham...
PubMed Articles
Familial antiphospholipid syndrome presenting as bivessel arterial occlusion in a 17-year-old girl.
This article presents a case of a 17-year-old girl with primary antiphospholipid syndrome developing subacute signs of hand and leg ischaemia caused by radiologically verified radial and popliteal art...
HELLP in the second trimester in a patient with antiphospholipid syndrome.
The syndrome of haemolysis, elevated liver enzymes and low platelets (HELLP) is estimated to occur in 0.01-0.2% of pregnancies and is considered a severe form of preeclampsia. It is associated with co...
The antiphospholipid syndrome causes venous, arterial, and small-vessel thrombosis; pregnancy loss; and preterm delivery for patients with severe pre-eclampsia or placental insufficiency. Other clinic...
Prolactin's role in the pathogenesis of the antiphospholipid syndrome.
Increased levels of serum prolactin have been reported in patients with various autoimmune diseases and have been associated with lupus disease activity. Currently, there is a lack of data regarding h...
Antiphospholipid syndrome and pregnancy.
Antiphospholipid syndrome is characterized by arterial and venous thromboembolic events and persistent laboratory evidence of antiphospholipid antibodies. Obstetric complications such as recurrent mis...
