Abstract P281: Acute Stroke Mimics: Etiological Spectrum and Efficacy of Stroke Assessing Scores

Introduction: Stroke mimics constitute a good number of patients referred as acute strokes within the window period for acute therapies. Proper triaging can avoid unnecessary imaging and even thrombolytic therapies in these patients. This study looked at etiological spectrum of acute stroke mimics presenting within the 4.5 hours therapeutic window. We also evaluated the FAST (Face-Arm-Speech-Time), BEFAST (Balance -Eyes-Face-Arm-Speech-Time) and the ROSIER (Recognition of Stroke in the Emergency Room) tools in picking true strokes. Methods: A prospective observational cohort study over a 2- year period; A descriptive analysis of various etiologies presenting as acute stroke was done. The presenting symptoms, signs and the diagnostic value of the FAST, BEFAST, and the ROSIER Scores in both the stroke mimics and true strokes were noted and the sensitivity and specificity for picking up the stroke mimics were calculated. Student’s t test, univariate analysis and multivariate logistic regression analysis were done. Diagnosis of stroke was confirmed by MRI. Results: After initial screening by Neurologists, stroke mimics constituted 328/1635 (20%) of referrals for acute stroke. Focal and generalized seizures with transient weakness and peripheral vertigo were the most common acute stroke mimics; followed by metabolic causes and psychiatric disorders. Females were more in the stroke mimic group (p = 0.02). Ischemic heart disease and atherosclerotic risk factors (except diabetes mellitus) were significantly higher among true strokes. 4 (1.2%) of the stroke mimics were treated with IV thrombolysis. Diagnostic accuracy for different stroke differentiating tools were: FAST (Sensitivity 85,9% specificity 52.8% Odds 6.8), BEFAST (Sensitivity 97.0% specificity 31.4% Odds 14.9) And ROSIER Scale (Sensitivity 85.7% specificity 59.4% Odds 8.7%). In Conclusion, Stroke mimics can constitute up to 20% of cases evaluated as strokes. None of the triaging tools appear to have enough accuracy. A proper history and clinical examination should be given priority over fixed protocols whenever acute stroke mimic are suspected, especially before administering acute costly interventions. Auditing stroke mimics is important to improve acute stroke pathways.