The Value of Signal Peptide-CUB-EGF Domain-containing Protein-1 (SCUBE1) in the Diagnosis of Pulmonary Embolism: A Preliminary Study

Abstract

The diagnosis of pulmonary embolism (PE) in the emergency department still poses difficulties because symptoms and signs are nonspecific. There is a need for more reliable noninvasive diagnostic tests to support clinical suspicion before the costly invasive procedures with complication risks still used in the diagnosis of PE. Signal peptide-CUB (complement C1r/C1s, Uegf, and Bmp1)-EGF (epidermal growth factor) domain-containing protein 1 (SCUBE1) is a novel, secreted cell surface protein expressed during early embryogenesis. The goal of this study was to compare the SCUBE1 levels between PE patients and healthy subjects and also investigate the value of SCUBE1 in the diagnosis of PE. Eleven patients diagnosed with PE using spiral computerized tomographic pulmonary angiography were included in the study. A control group of 23 age-matched, healthy volunteers served as a reference for biochemical parameters. Mean (±SD) SCUBE1 levels were 72.0 (±32.6) ng/mL in the patients with PE and 31.4 (±13.8) ng/mL in the control group. SCUBE1 levels were significantly higher in the patients with PE (p = 0.001). Receiver operating characteristic (ROC) curve analysis was performed to determine cutoff thresholds in discriminating between PE and control group plasma SCUBE1 levels. Area under the ROC for that purpose was 0.862 (95% confidence interval [CI] = 0.70 to 1). A SCUBE1 cutoff point in patients with PE > 46 ng/mL had specificity and sensitivity of 91% (95% CI = 0.70% to 0.98%) and 82% (95% CI = 0.48% to 0.97%), respectively. This preliminary study suggests that plasma SCUBE1 values have a good level of specificity for PE and may be of use in the diagnosis of PE. Further studies involving larger case series and also clinical studies are needed to corroborate these findings.