Welcome to the Exeter Clinical Laboratory International website
NHS logo

Beta Trace Protein (?CSF leak)

Blood Sciences Test


Please collect minimum 0.5 ml into a white lid clear universal tube.

Test Usage

The leakage of cerebrospinal fluid (CSF) into nasal, oral or ear cavities or from a dermal sinus and its subsequent drainage from these cavities may be caused by trauma, intracranial surgical procedures, infection, hydrocephalus, congenital malformations and neoplasms. The most severe consequence of a CSF leak is microorganism contamination and the development of meningitis.


  • Prevalence – 70-80% are related to accidental trauma
    • 2-4% of head injuries result in CSF leaks
  • Age – middle age for spontaneous leaks, newborn for dermal sinuses


  • Trauma
  • Non-traumatic:
    • Surgery (usually spinal or neurosurgery)
    • Postoperative defect
    • Infection
    • Tumor obstruction
    • Congenital defects (at the base of the skull or at the end of the spinal cord)
    • Hydrocephalus
    • Spontaneous – no known defect or trauma


  • Beta trace protein is found mainly in the CSF
  • Interruption of the anterior cranial fossa floor allows leaks through the cribriform plate
  • 80% of post-traumatic leaks occur in first 48 hours post-trauma

Clinical Presentation

  • CSF leakage most commonly presents as otorrhoea or rhinorrhoea
  • Patient may complain of salty or sweet taste; intermittent clear nasal discharge exacerbated by Valsalva maneuver


  • Indications for testing – presence of otorrhoea or rhinorrhoea; patient with recurrent episodes of meningitis
    • Laboratory testing
    • Chemical analysis (eg, Glucostix) of the fluid for glucose and protein is unreliable in determining the presence of CSF fluid
    • The presence of Beta trace protein indicates CSF leakage (high specificity and sensitivity)
    • False positives – chronic renal failure
  • Imaging studies
    • Radiographic studies, with or without intrathecal injection of dye or radioisotope, are not always successful in demonstrating small or delayed CSF leaks
    • High resolution CT is initial study of choice
    • MRI
    • Cisternogram by CT or MRI

Turnaround time

Approx 1 month


Test referred to Neuroimmunology Unit, National Hospital for Neurology and Neurosurgery, Queen Square, London.

Specimen Labelling Procedure
University of Exeter logo
UKAS Medical logo


Royal Devon University Healthcare logo