Diagnostic Testing for Coagulopathies in Patients With Ischemic Stroke

Abstract

Background-Hypercoagulable states are a recognized, albeit uncommon, etiology of ischemic stroke. It is unclear how often the results of specialized coagulation tests affect management. Using data compiled from a systematic review of available studies, we employed quantitative methodology to assess the diagnostic yield of coagulation tests for identification of coagulopathies in ischemic stroke patients. Summary of Review-We performed a MEDLINE search to identify controlled studies published during 1966 -1999 that reported the prevalence of deficiencies of protein C, protein S, antithrombin III, plasminogen, activated protein C resistance (APCR)/factor V Leiden mutation (FVL), anticardiolipin antibodies (ACL), or lupus anticoagulant (LA) in patients with ischemic stroke. The cumulative prevalence rates (pretest probabilities) and positive likelihood ratios for all studies and for those including only patients aged Յ50 years were used to calculate posttest probabilities for each coagulopathy, reflecting diagnostic yield. The cumulative pretest probabilities of coagulation defects in ischemic stroke patients are as follows: LA, 3% (8% for those aged Յ50 years); ACL, 17% (21% for those aged Յ50 years); APCR/FVL, 7% (11% for those aged Յ50 years); and prothrombin mutation, 4.5% (5.7% for those aged Յ50 years). The posttest probabilities of ACL, LA, and APCR increased with increasing pretest probability, the specificity of the tests, and features of the patients' history and clinical presentation. Conclusions--The pretest probabilities of coagulation defects in ischemic stroke patients are low. The diagnostic yield of coagulation tests may be increased by using tests with the highest specificities and by targeting patients with clinical or historical features that increase pretest probability. Consideration of these data might lead to more rational ordering of tests and an associated cost savings. (Stroke. 2000;31:3067-3078.)

Evaluation of Cryptogenic Stroke With Advanced Diagnostic Techniques

“…59 Therefore, laboratory tests for coagulopathy may be reserved in selected patients. In clinical practice, a much more important cause of coagulapathy is cancer.…”

Testing for Inherited Thrombophilias in Arterial Stroke

“…All are inherited through autosomal-dominant transmission and all have been associated with an increased risk of VTE; however, none has convincingly been demonstrated to be risk factors for arterial thrombosis. [1][2][3] Homozygosity for these defects significantly enhances the risk of thrombosis; however, homozygotes are rare and the bulk of the data presented here comes from heterozygotes.…”

Percutaneous Atrial Septal Closure in Immunocompromised Patients

“…Autoimmune disease also may induce a prothrombotic state promoting stroke, such as an HIV patient with protein C and protein S deficiency who developed a stroke in the presence of a PFO [15]. The prevalence rates of anti-cardiolipin antibodies in patients with ischemic strokes were 17-21% [16]. A retrospective case series of 40 patients showed that anti-phospholipid antibodies and hypercoagulability is common in patients with PFO [17].…”