Rapid, accurate and non-invasive detection of cerebrospinal fluid leakage using combined determination of β-trace protein in secretion and serum

• Published in: Clinica chimica acta 2005, Vol.351 (1), p.169-176
• Main Authors: Risch, Lorenz, Lisec, Ivan, Jutzi, Markus, Podvinec, Michael, Landolt, Hans, Huber, Andreas R.
• Format: Article
• Language: English
• Subjects: Adult; Aged; Biomarkers; Cerebrospinal Fluid - physiology; Cerebrospinal fluid leak; Craniocerebral Trauma - cerebrospinal fluid; Ear - injuries; Female; Glomerular filtration rate; Humans; Intramolecular Oxidoreductases - blood; Intramolecular Oxidoreductases - cerebrospinal fluid; Lipocalins; Male; Middle Aged; Nephelometry and Turbidimetry; Neurosurgical Procedures; Nose - injuries; Prospective Studies; Prostaglandin D synthase; Radiography; Reference values; ROC Curve; Sensitivity and specificity; Skull Fractures - cerebrospinal fluid; Skull Fractures - diagnostic imaging; Transferrin - cerebrospinal fluid; β-Trace
• ISSN: 0009-8981; 1873-3492
• DOI: 10.1016/j.cccn.2004.09.008

β-Trace protein (Btp) has been proposed as a valuable marker of cerebrospinal fluid (CSF) leakage overcoming the drawbacks of β-2-transferrin (B-2Tr) determination. However, there is still controversy about the appropriate cut-offs to be used (range 0.35–6 mg/L). The aim of the study was to evaluate cut-offs of Btp determination for detection CSF leakage. Further, we assessed whether the Btp secretion to serum ratio (Btp-sec/ser-ratio) would add diagnostic value. Prospective study in patients with suspected CSF leakage. Quantitative determination of Btp in secretion and serum (Dade-Behring) and qualitative measurement of B-2-Tr in secretion and serum. Results were assessed in view of clinical data. Cut-offs and diagnostic characteristics were determined by ROC analysis. A total of 176 samples were assessed originating from 105 patients. In 43 samples CSF leakage could be confirmed. Sensitivity of B-2-Tr was 84%, specificity amounted to 100%. The area under the curve (AUC) for Btp-measurement in secretion was 0.98. At a cut-off of 0.68 mg/L, sensitivity was 100% and specificity 91%. At a cut-off of 1.11 mg/L, the specificity was 100% with a sensitivity of 93%. The Btp-sec/ser-ratio has an AUC of 0.99. Combining a 0.68 mg/L cut-off in secretion with a Btp-sec/ser-ratio cut-off of 4.9 reveals a sensitivity of 99% and a specificity of 100%. Btp is a rapid and accurate marker for the presence of CSF leakage. Combining measurement of Btp in secretion together with determination of the Btp-sec/ser-ratio enhances the diagnostic characteristics of the Btp assay. Determination of Btp in both serum and secretion is thus recommended.