Clinical experience with beta-trace protein as a marker for cerebrospinal fluid.

beta-Trace protein is an immunological marker for the detection of cerebrospinal fluid traces. The aim of the study was to evaluate the predictive value of the beta-trace protein test. We investigated 145 specimens for cerebrospinal fluid using beta-trace protein. All case notes were retrospectively reviewed and tabulated for indication and procedure with focus on outcome. The specimens were analyzed by immunoelectrophoresis. beta-Trace protein was detected in 62 specimens and was absent in 83. In correlation with the clinical course, the clinical findings, the results of high-resolution computed tomography of the paranasal sinuses or petrous bone, computed tomographic cisternography, magnetic resonance imaging, indium 111-pentetic acid radionuclide cisternography, intraoperative findings, and visualization using sodium-fluorescein, there were no false-positive results. In 6 cases, a false-negative result occurred. The overall accuracy was 95.68%. The beta-trace test has a specificity of near 100% and a sensitivity of 91.17%. Analysis of beta-trace protein is a valuable test and has some advantages in comparison with the beta2-transferrin assay.