Urinary 11-dehydro-thromboxane B-2 and coagulation activation markers measured within 24 h of human acute ischemic stroke

The aim of this study was to determine the extent of change in platelet and coagulation markers in the acute phase of ischemic stroke and to assess th e utility of marker measurement in stroke subtype classification. Urinary 1 1-dehydrothromboxane B-2 (11-dTXB2), a marker of in vivo platelet activatio n, and markers of coagulation activation, including prothrombin fragment 1 + 2 (F1 + 2), thrombin-antithrombin complex (TAT), and fibrinogen, were mea sured in 25 patients with ischemic stroke within 24 h of onset of symptoms. Marker levels in patients with ischemic stroke were compared with those in 19 age-matched controls who had not taken aspirin for at least 2 weeks bef ore sampling and 25 healthy controls. Median marker levels were significant ly increased in stroke over those in age-matched controls for fibrinogen (3 44 vs. 289 mg/dl; P = 0.030), F1 + 2 (1.40 vs. 0.80 nmol/l; P = 0.003), and TAT (6.65 vs. 2.20 mug/l; P < 0.0001). Median marker levels for seven pati ents with cardioembolic stroke and 18 with non-cardioembolic stroke were no t significantly different for any marker test. Eight patients taking aspiri n at the time of the stroke had significantly lower 11-dTXB2 values than pa tients not taking aspirin (964 vs. 4,314 pg/mg of creatinine; P = 0.007). S troke patients not taking aspirin had significantly higher 11 -dTXB2 concen tration than age-matched controls (4,314 vs. 1,788 pg/mg of creatinine; P = 0.006). Coagulation and platelet activation markers are increased in the a cute phase of stroke regardless of the clinical mechanism. This finding sug gests that the markers may not be useful for predicting clinical subtype of ischemic stroke in the acute phase. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.