Performance of GFAP and UCH-L1 for Early Acute Stroke Diagnosis in the Emergency Department.

: Rapid identification and treatment of stroke are essential for the patient. Our objective was to determine the diagnostic utility of glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase L1 (UCH-L1) in the emergency department to identify and differentiate acute stroke within 4.5 h of symptom onset in patients admitted with a stroke code alert. This study included 85 patients with a "code stroke alert" upon arrival at the emergency department. Individuals were grouped in two categories: patients with stroke (including 69 patients) and patients without stroke (including 16 patients). The research was conducted at the Emergency Municipal Clinical Hospital in Timișoara, Romania, the county's second-largest hospital, which lacks a neurologist and a dedicated stroke unit. No significant differences were observed between the two groups (with stroke and without stroke) regarding most demographic or admission parameters. Significant differences were observed for the biomarkers GFAP (142.91 ± 102.19 pg/mL in patients with acute stroke vs. 37.76 ± 19.92 pg/mL in patients without stroke ( < 0.001)) and UCH-L1 (1307.68 ± 967.54 pg/mL in stroke patients vs. 189.81 ± 92.69 pg/mL in patients without stroke ( < 0.001)). Within the stroke group, 37 patients had acute ischemic stroke, while 32 patients were diagnosed with hemorrhagic stroke based on brain CT imaging. GFAP achieved an accuracy of 94.2% for differentiating hemorrhagic from ischemic stroke, with a cut-off value of 77.15 pg/mL. GFAP excellently differentiated acute stroke from stroke mimics, with high sensitivity, perfect specificity, and strong predictive values. Integrating GFAP and UCH-L1 measurements into emergency protocols may enhance stroke diagnosis, optimize patient triage, and ultimately improve outcomes by facilitating the faster initiation of appropriate therapies.