Background: This study aimed to compare changes in plasma beta-globin DNA and serum S100 protein to diagnose stroke and for predicting mortality and morbidity.
Methods: Patients with stroke-like symptoms presenting to the emergency department of a Hong Kong hospital were recruited. Plasma DNA was analyzed for the beta-globin gene with fluorescent-based PCR. S100 concentrations were determined using ELISA. Primary outcomes were diagnosis of stroke, mortality, and modified Rankin Score (mRS) after 6 months.
Results: One hundred ninety-seven consecutive patients recruited, 118 (60%) ischemic stroke, 35 (18%) hemorrhage and 44 (22%) with no acute neuroimaging changes. Serum S100 and plasma DNA were increased in 126 (p<0.0010) and 36 (p=0.21) stroke patients respectively vs. controls. Median plasma DNA was higher in hemorrhagic stroke than those without (1725 vs. 1050 kilogenome-equivalents/l, p=0.0104). Median plasma DNA was higher in mRS>2 vs. mRS<or=2 (1350 vs. 1025, p=0.0103), and higher in non-survivors vs. survivors (1625 vs. 1050, p=0.0070). Median serum S100 higher in mRS>2 patients vs. mRS<or=2 (0.152 vs. 0.131 microg/l, p=0.0003). The odds ratio (OR) of discriminating hemorrhagic from non-hemorrhagic stroke with DNA was 4.24 (95% CI 1.88-9.56); S100 and DNA together give an OR of 16.55.
Conclusion: For stroke diagnosis, S100 performs better than DNA; DNA is a better marker for hemorrhage. For diagnosis of hemorrhagic stroke, combined S100 and DNA performs better than either alone. Plasma DNA and serum S100 predict morbidity and mortality in stroke.