Diagnosis of Acute Ischemic Stroke using Blood Biologic Markers in the Emergency Department

Yeo, Woon Hyung; Seo, Dong Woo; Oh, Bum Jin; Kim, Won; Lim, Kyoung Soo

Abstract

PURPOSE: In patients with acute neurological symptoms, brain computed tomography (CT) is usually used to exclude hemorrhagic stroke. After CT imaging, there is no rapid, effective biologic marker for differentiating between acute cerebral ischemia and other etiologies, precluding rapid triage for further evaluation. We evaluated the diagnostic value of a panel of biochemical markers.
METHODS
We performed the Triage Stroke Panel (Biosite Inc., UK) test using blood samples of patients who were admitted to the emergency department with suspected acute stroke between December, 2007, and March, 2008. The TSP is represented as MMX (multimarker index) compiles from individual biomarker values, based on quantitative measurement of B-type natriuretic peptide (BNP), fibrin degradation products containing D-dimer, matrix metalloproteinase-9 (MMP-9), and S100. All patients were prospectively evaluated with imaging and laboratory tests for final diagnosis.
RESULTS
Of 105 patients, 51.4% had ischemic stroke and 48.6% had non-ischemic, non-organic abnormalities, primarily peripheral vertigo. High levels of BNP and MMX were observed in patients with ischemic stroke (both p <0.001). Independent predictors (odds ratio with CIs are given) of ischemic stroke were: female (OR=0.1 [0.2-0.8]), hypertension (OR=5.0 [1.2-21.3]), BNP (BNP >54.7 pg/mL, OR=99.4 [8.5-1,171.0]). A model combining BNP and MMX had 92% specificity and a 91% positive predictive ratio for prediction of acute ischemic stroke.
CONCLUSION
Using biomarkers may improve the differential diagnosis of ischemic stroke after initial brain CT imaging for hemorrhagic stroke, rapidly guiding further evaluation and treatment initiation in the emergency department.