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Beta Trace Protein (?CSF leak)

Blood Sciences Test


Specimen

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.

Epidemiology

  • 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

Etiology

  • 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

Pathophysiology

  • 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

Diagnosis

  • 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

Availability

Referred test

Specimen Labelling Procedure
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